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suspendedhatch 04-12-2008 01:52 PM

Realize the full Performance/Economy Potential of a Honda Civic VX
Topic Index
Page 1
Introduction, Goals
Distributor-less Ignition, Waste Spark
Engine Swap
Balanced / Blueprinted Injectors
Initial Dyno Tune
Recommended Reading (Tuning)
LSD Transmission
Weight Reductions / Additions
Gassavers Myths
Planned Mods
Other Mods
Advantages of Direct Fire Ignition
CDI Module

Page 2
D16Y5 and D16Y8 DFCO specs (grasshopper)
Dyno Graph
Distributor-less Conversion
Salt Lake to Albuquerque trip photos

Page 3
Things I'm Doing that Don't Help FE
O2 Target Table
O2 Target Table with Driving Conditions superimposed on it

Page 4
AEM EMS VTEC and VTEC-E Controls
Interpolation and Resolution
Smog Test
Integra DA Wish List
Injector Phase Tuning Benefits
Ignition Timing
Tuning Part Throttle Ignition Timing
Ignition vs Idle Target
P2J ECU VTEC and VTEC-E Pinouts / Wire Colors (grasshopper)

Page 5
Honda Civic Alignment / Tire Wear
Low Temp Thermostat
Updated Pics
Wish List
Injector Phase Tuning
Spoiler Fix
D15Z7 Helms Manual (spanish)
Ignition Timing
D15Z7 OEM specs!!!
D15Z7 5 Speed Gear Ratios
D15Z7 Cam Lobe Height
Valve Relief

Page 6
Valve Adjustment
Winter Tire Choice
Tire Size for HX Rims on a 5th gen Civic
HX Rims, Integra Brakes


Having owned several Hondas and never been fully satisfied, I decided to rethink exactly what my ideal car would be. What I came up with is that I want a car that has great handling, great braking, great power, and great economy. Essentially I want better performance than a Civic Si and better FE than a Civic VX (these being the only vehicles I could afford that have double wishbone suspension front and rear and an exceptionally low coefficient of drag matched to an economical motor). It seems like a pipe dream. But it just so happens that Honda had the same idea.


From 1996-1999 Honda produced a motor that combined VTEC-E and VTEC into one. They didn't bring this motor to the United States. In Japan the block was stamped D15B. Across the rest of the eastern hemisphere, the block was stamped D15Z7.


So last August I sold my Civic DX automatic that had a SOHC VTEC swap and bought a lowly Civic VX. I decided that I needed a chassis change because I wanted a manual transmission and I wanted many things that are only found on the VX, ie the rear diffuser, front lip spoiler (also found on Si), aluminum lower alternator mount, aluminum front lower driver's side engine mount, less sound deadening weight, "VTEC-E" valve cover, and lightweight alloy rims.


First thing I did was lock the car in the garage until I could install some serious car alarm security. It is a Honda afterall. "Honda" is synonymous with "stolen".

Then I did some maintenance on the motor and drove it that way for several months to give me a good baseline. My FE goal would be based on my own personal driving habits and my goal is to exceed this baseline w/out any sneaky tricks like driving like a near-sighted grandmother. My baseline avg was 38 mpg mixed, 44 highway.

The Rules
Which brings me to "the rules". To the general public, the car must outwardly appear to be stock; in other words, it's going to be a sleeper. I don't want to draw any attention from thieves, street racers, cops, or ricers.

Secondly, the car must outperform both the VX and the Si.

Third is not so much a rule as a constraint. My salary requires a very limited budget with long periods of time between expenditures.


So luckily, I already had the AEM EMS. "WHAT?! You have an EMS? Don't those go for thousands of dollars and require hundreds of dollars to have professionally installed and tuned?" Yes and yes. But I got one for $1100 in 2001 (at-cost to help with development), and I have a friend that is a professional tuner. It's a good thing too, because there is no other viable option available for me to realize my goal. Hondata simply isn't capable.


AEM Gauge-Type Wideband O2
The next piece of equipment that I would need so that I could run lean mixtures is the AEM Gauge Type UEGO Controller. $260 ouch. But it's cheaper than competing products and far superior.


suspendedhatch 04-12-2008 04:13 PM

Distributor-less Ignition

The AEM EMS allowed me to convert to distributor-less ignition. This allows much more precise control of the ignition timing. Four small coils are more efficient than one large coil because they have more time to charge before they fire (aka dwell). The AEM Twin Fire CDI Ignition module doubles the voltage and amperage of the ignition system. I bought some used Honda CBR coil-on-plugs (this was before AEM came out with the pencil coils) and a used MSD DIS-4. The DIS-4 was bad so I worked out a rent-to-own deal with my homeboy Scottie for his AEM Twin Fire since he blew up his race car anyway. Here is my write-up of the install: Coil -On-Plug Conversion

Note that you can see the distributor in the picture. At the moment I can't afford a AEM EPM ("engine position module"). On a Honda, the cam and crank sensors are typically found inside the distributor. This is the reason why Honda distributors are so unreliable. The distributor also plugs a hole in the valve cover. The EPM replaces the distributor completely. It plugs the hole and provides a replacement hall-effect sensor to replace the weak factory cam sensor. The stronger AEM sensor is accurate into very high RPMs while the factory sensor tends to "wander" even within the factory redline and is vulnerable to ignition "noise".

Waste Spark
I wired the coils and configured the EMS for waste spark. Waste spark means that in addition to firing the coil at the correct time, you also fire it on the exhaust stroke. In theory this might reduce emissions, but I remain skeptical until I can see the results with a gas analyzer. It just so happens that I've been given the unfortunate opportunity to do a before/after emissions test (that's right I failed emissions and got a free re-test, might as well convert to DIS first). **Waste spark does not appear to help emissions. My HC's are higher than I would like.


Engine Swap @ Motiva
I drove the car from San Diego to Albuquerque to enlist the help of my best friend Scottie at Motiva Performance Engineering. The guy is a genius and one of the few people who understands and respects my goals for the engine. He swapped the engine and tuned the EMS while I mostly took pictures.

Balanced and Blueprinted Injectors
I swapped over my 240CC OBD1 VTEC injectors which had been balanced and blueprinted by RC Engineering. This not only improves fuel flow but also the spray pattern. The result is injectors that are better than brand new factory injectors and that are more consistent from one cylinder to the next, resulting in a more accurate O2 reading so the ECU has more accurate control of the overall AFR.

And with that, the 220k mile factory D15Z1 and tranny went to the big recycler in the sky.


Peak HP / Torque
The end result of tuning was 119hp and 99ft/lbs at the wheels! So at this point I have already exceeded the Si's power. The picture above shows over 30 dyno pulls (I think it only shows 9 at a time). The crazy spikes were caused by Scottie doing a long dyno pull with shifting. The time in the bottom right corner indicates that we finished tuning at 4:30AM.

He got the car to start up and idle reasonably well. We did some street tuning, and then I headed back to Salt Lake where I was left with finishing the street tuning myself. At this point I will recommend some reading material.

Recommended Reading (Tuning)
How to Tune and Modify Engine Management Systems: Jeff Hartman
Building and Tuning High Performance Fuel Injection: Ben Strader
Engine Management Advanced Tuning: Greg Banish
AEM EFI Basics: (download from their forum)

I will talk a great deal about tuning a standalone for economy at a later date.

HX Wheels
As for the physical wrenching on the car, the puny 13 inch VX alloys wouldn't fit the Integra front brakes, so I sold them and found a set of 14 inch lightweight HX rims. They could easily be mistaken for VX rims when seen on a 5th gen Civic. The Integra front calipers require a little bit of grinding or a spacer in order to fit the rim.


You wont find HX wheels on ebay. If you find them on craigslist, they're painted and/or curbed. They're a ricer's favorite. Car-parts.com will search the nation's salvage yards. I found a set of three at a local junkyard and picked up the forth later.


OBD1 LSD Transmission
The transmission I chose is from the earlier generation JDM D15B. This tranny has factory LSD and the SOHC VTEC gear ratios. Clearly this is not the most economical trans available, but remember that my goal is to exceed the stock VX economy; not get the most economy I possibly can. So this trans suits my overall goal of the ultimate daily driver.

Lightweight Flywheel
I replaced the flywheel with an 11lb Exedy flywheel and OEM replacement clutch. If you go too light with the flywheel it will waste gas because you will have to rev high to leave from a stop. The Exedy is only a couple lbs lighter than the stock VX flywheel, which in turn is lighter than the other SOHC flywheels.

Weight Reduction
I have been reducing weight where it is not perceptible to the driver or occupants.

Retained the VX's lightweight Alternator Mount
Retained the VX's lightweight Engine Mount
Removed Intake Manifold Bracket
Removed Rear Speakers
Removed front and rear Bumper Supports
Removed SRS System
Removed Driver's Knee Bolster
Removed Spare, Jack, and Tools
Removed Ignition Coil, Rotor, Ignitor, Plug Wires
Replaced Steering Wheel with a smaller non-SRS wheel
Replaced cast iron exhaust manifold w/ SS Header
Replaced intake pipe with aftermarket CAI
Replaced battery with Odyssey PC680MJT
Replaced suspension with Tokico RAK Coilovers
Swapped DC Integra front seats
Installed lightweight Rims (15in Rota Slipstreams for summer, 14in HX's for winter)
Installed lightweight Flywheel

Weight Additions
I've easily added as much weight as I've removed, and will probably add some more weight down the line. I like to think of it as getting rid of dead weight. The weight you add is functional and increases the useability of the vehicle. It's the same concept as adding a roll cage to a race car that has been stripped of it's interior. These are the items I feel are significant (included some negligible stuff).

90-91 Civic Si 15/16 brake Master Cylinder
DC Integra front/rear brake swap
Neuspeed front upper Strut Tower Brace
DC Integra front lower Crossmember Brace
DC Integra GSR front Swaybar
Progress 24mm adjustable Rear Swaybar
Larger diameter and wider Tires
AEM Twin Fire ignition module
CBR Ignition Coils
D15Z7 vs D15Z1 (slightly heavier?)

And before anyone makes a dumb internet comment, I'd like to say that I'm 7% body fat. I always have been.


suspendedhatch 04-12-2008 04:22 PM

I'd like to take a short break from that and quickly dispel some FE Myths I've come across on this forum and others.

Coasting to a stop in neutral USES MORE GAS than coming to a stop in gear. Fuel injected vehicles have a strategy called DFCO, or Deceleration Fuel Cut Off, which means that when you foot is off the throttle and the RPMs are above 1000, the injectors are TURNED OFF. This is possible because it's inertia keeping the engine rotating. The wheels push against the transmission which pushes against the crank. When you put the car in neutral, you disconnect the crank from the trans. The RPMs drop to idle rapidly, and the ECU turns on the fuel injectors to idle the engine.

Shutting down your engine at a red light wastes gas because it takes an enormous amount of gas to start a car. When I was delivering pizza I would average 5mpg less than normal, and the only difference was all the short trips requiring me to start the vehicle.

Running lean at all times does not increase fuel economy. Running too lean can hurt mileage under certain operating conditions, such as acceleration. Running lean benefits FE under cruise conditions, but not if you run so lean that the loss in power requires and increase in throttle.

I saw someone's post where they mentioned running an AFR of 10:1 on a stock motor "for best power". Best power on most modern engines is right around 13.2, and manufacturers will run in the neighborhood of 12.5 for engine safety. 10:1 is insanely rich. It will cause bore wash which means you clean the oil off the cylinder walls increasing engine wear and in turn blowby and weak compression. I consider that a waste of gas even though you are at full throttle and not concerned about mileage.

suspendedhatch 04-12-2008 04:33 PM

Planned Modifications
Tuned Intake Pipe
Electric Water Pump
Cruise Control
Antenna Delete
Get a 1/4 Mile Time
Install "VTEC-E" Valve Cover
Endyn Roller Wave high compression N/A Pistons
Tune the individual cylinder trims
Tune the injector phasing
Tune the Part Throttle Ignition Timing and VTEC-E Crossover on a load-bearing dyno

Soon I plan on redoing my crappy custom exhaust. I'm going to order some 2.25in mandrel bends, two 18in long Magnaflow Resonators, and most likely I'll retain my 2.25 Magnaflow Muffler.

suspendedhatch 04-12-2008 05:11 PM

I'm sorry about the seeming lack of continuity and contradiction in time flow from one paragraph to the next. The truth is (not only am I a scatterbrain at the moment), some things were tried, didn't work, were put back to stock, and then later executed successfully. Other details of the timeline were contracted just for the sake of brevity.

GasSavers_Erik 04-12-2008 05:41 PM

More mpg than a VX and more power than an si would be a great combo, especially for the ppl that think that gas saving cars can't merge safely into fast traffic.

I'm looking forward to seeing your gas log when you get your vehicle in the garage.

suspendedhatch 04-12-2008 06:24 PM

When I'm tuning the car I get as low as 31 mpg. When I drove to Salt Lake from San Diego I averaged 44 mpg. When I was exploring the city and looking for houses to rent, I averaged 36 mpg. I've spent a lot of time on the ignition, idle, and start up since then. But it's going to be a while until I can go without tuning between fill ups to see what mileage I'm at currently.

Tuning wastes gas cuz you spend an hour or two idling in the driveway, or starting and stopping the engine 20 times, or purposely driving inconsistently to reach each load/rpm cell. Not to mention driving with your foot on the brake and driving up hill in too high of gear to reach those pesky very high load / very low RPM cells.

I wish I had my own load bearing dyno.

civic94 04-12-2008 08:14 PM

well i have a ex/si tranny on mines, and i averaged 45 mpg when i had a 50/50 city and highway commute. its all in how you drive it

my best was 55 mpg averaging 50 miles per hour on a trip

well its a great thing that your trying to get more power and efficiency out of a civic, but it would be nice if the transmission can be like a si tranny from gears 1-5, and 5th gear is just like a vx one

DRW 04-12-2008 08:26 PM


Originally Posted by suspendedhatch (Post 95833)
Fuel injected vehicles have a strategy called DFCO, or deceleration fuel cut off, which means that when you foot is off the throttle and the RPMs are above 1000, the injectors are TURNED OFF.

Since you have EMS, can you change the DFCO rpm? I've lowered mine to about 938 when the engine is fully warm, it's higher when the engine is cold. It's a nice mod since there is very little engine braking at low rpm! I can coast in gear for a good distance without slowing much.


Originally Posted by suspendedhatch
I saw someone's post where they mentioned running an AFR of 10:1 on a stock motor "for best power". Best power on most modern engines is right around 13.2, and manufacturers will run in the neighborhood of 12.5 for engine safety. 10:1 is insanely rich. It will cause bore wash which means you clean the oil off the cylinder walls increasing engine wear and in turn blowby and weak compression. I consider that a waste of gas even though you are at full throttle and not concerned about mileage.

That's an interesting interpretation. I suspect you're responding to something I wrote in 'Remapping the ECU for lean burn'? I've edited two of my posts to make them a little clearer. This one: https://www.gassavers.org/showpost.ph...5&postcount=21
and this one: https://www.gassavers.org/showpost.ph...98&postcount=5
Thanks for the feedback.

VXRider 04-12-2008 09:28 PM

This is a great thread, I'm interested to see how your car turns out. I'll definitely be following.
Keep it up!

suspendedhatch 04-13-2008 11:35 AM

Hey wow, some positive comments. I'm not used to that on a forum. I think I like this place.

The EMS allows you to control DFCO based on load, RPM, TPS, and coolant temp. You can also have DFCO by default by zero'ing out your fuel table at very low load all the way down to Idle RPM.

The EMS gives you more control than you could ever imagine. It also has better resolution (more break points) than the factory ECU. You can use a separate map for the 2nd stage VTEC (16 valve mode) by using the N20 or boost functions.

I'll check out those threads you posted tonight.

My tranny has the same gearing as the EX/Si, just with the addition of LSD. My trip to Salt Lake from San Diego was at 75-80 mph and I averaged 44mpg. I suspect that I would get even better mileage today but I don't use the freeway much around here so I don't have any updated freeway mpg figures.

One day I want to add aftermarket cruise control because I've read that it can increase your mileage by 7%.

This setup has been a dream come true and the realization of a number of different setups all rolled into one (lots of leftover parts!). I'm glad you guys can take interest in it because right now it absorbs all of my free time.

GasSavers_topher 04-13-2008 12:04 PM

Very nice build man. It is nice to know that there are others out there who prefer a combination of power and FE.:thumbup:

suspendedhatch 04-13-2008 10:34 PM

Some very knowledgeable and dedicated people here. I can't wait until we can all start building off of each other's experiences.

My other mods are an ebay CAI that I selected because it's 2.25 inch diameter; matched to an AEM dryflow filter. An old hand me down DC 421 2 piece stainless steel header. A Magnaflow high flow cat converter 2 inches in, 2.25 out. Custom crush bent 2.25 inch piping all the way back. Magnaflow 2.25 ID straight through muffler.

The entire cat back exhaust is going to be redone. I will reuse the muffler, but get some mandrel bends and add two straight through resonators to the straight section of the pipe to make it quiet.

Battery is a lightweight Odyssey PC680MJT. In my old car I had this mounted with their sheet metal piece so that I could remove the heavy OEM battery tray and heavy duty bolts. I haven't got to it on my new car. I don't think I want the battery in the back this time around.

Suspension is the Tokico RAK coilovers. Ride height has been lowered 1.5 inches.

*Forgot that I have a Hondata-knockoff "heat shield" intake manifold gasket.

suspendedhatch 04-14-2008 10:45 PM

(The following is in response to topher in his thread but I started babbling on and on about my project and some childish revenge so I'm posting it here.)

I'm familiar with his post (bense's on Honda-Tech). I'm not very fond of his attitude. At the beginning, he's naive and overly optimistic. He builds up the D16Y5 as the greatest thing on earth. Then as things progress he has some problems (due to him over expanding his plans) and he gets very frustrated. Finally he gives up altogether and decides to focus all his attention on building transmissions. He concludes that you're better of just getting a D16Z6 (or something to that effect). Juxtapose that against his first post.

He was very rude to me on another forum that other people were ganging up on me for having a solid but controversial opinion. I believe that was D-series.org, one of maybe 10 forums I have tried and then abandoned. People don't like to be wrong and they can suck it. I don't enjoy being wrong but I try to keep my personal pride out of it and LEARN SOMETHING NEW.

The lesson I learned from bense's post is not to bite off more than you can chew. Start with one experiment, get it working, then build on it in stages. My project is huge. If I had tried to do it all at once, I would most certainly have failed. Get the engine running on a OEM ECU. Then get it running on the EMS. THEN convert to DIS. Then do a conventional tune for max power with VTEC. Then tune it to run reliably and efficiently. THEN optimize the tune to run lean, run VTEC-E, run DFCO and run the advanced features.

As it happens most of what I am doing on this project has already been done on my previous projects and I'm simply re-using the old parts. The only difference is the motor. It has not been easy tuning this engine but luckily I can focus solely on accomplishing that. The most notable aspect of this project is that I daily drive this car every day. At the moment it is my only transportation as my Integra has a blown trans.

I have not met bense in person and I will be careful to judge him. But I will not deny that I take a great deal of satisfaction in the fact that to my knowledge, for all the flak people have given me on various forums, no one has pioneered this motor to the extent that I have and had such success at it. None of the very negative and judgmental people at D-series.org, SOHC Honda, etc etc etc will be able to hold a candle to my project when it's completed. It will not be the most powerful D series, but it will be the best combination of economy and power which I believe to be the ultimate formula for a great daily driver.

I owe this entire project to my friend Scottie at Motive Performance Engineering in Albuquerque. He is the real brains behind it. He inspired me towards the VTEC-E motors when he swapped a Y5 head onto his 92 DX motor, installed an old school wideband controller, and tuned it with the very same hand-me-down EMS that has changed hands from me to him and then back to me (this was back before bense was even familiar with the term "VTEC-E"). He drove that car to work from Phoenix to a dyno shop in Whittier CA and back every week and would brag to me about how far he could lean it out at cruise and how much mileage he could squeeze out of it (this was at the time when I was saving up for a B16A). Unfortunately he drove that car off an embankment in the rain and was caught sideways by a tree. The car was sold for parts, but the spirit of it lives on in my VX.

suspendedhatch 04-14-2008 10:48 PM

So you have a bisi cam... that's cool. I have bisi to thank for AEM coming out with the pencil coils and the EPM. I wouldn't mind having some bisi parts on my car...

thisisntjared 04-15-2008 08:24 AM

you are somewhat accomplishing what i wanted to without going through the trouble of tuning. i had a goal to have a civic that would outperform an integra while get the mpg of a 92-95 dx hatch

my solution was a 94 cx with a d16z6 swap with intake header and exhaust. along with hx rims and a fully built suspension. that car was as quick as my si is now, handled better and got way better gas milage. i do believe that your hatch as it sits now had the power/mpg beat on my hatch.... but i think you have a ways to go with handling. tires are probably the most annoying decision because you are either satisfying performance or (fuel)economy, but never both. if you try to compromise, after time, you will be happy with neither.

also regarding the dfco, you have to be careful what you do here. there is no doubt that you probably found a creative solution for this, however if it becomes too low then you run the risk of the motor stalling when it first drops down to idle before it has time to rebound because of the lighter flywheel. if you dont mind my asking, how did you handle things, like approaching idle, with the lightweight flywheel.

also what are your opinions to the readily available, user friendly, and affordable vafcII? i was thinking about getting one because they are alloud in sts and i have a header on my si.

either way kudos to you for making this work, you definitely have no explored all the options yet for fuel economy and/or performance so i look forward to see how things turn out later. do you still post on ht? i did enjoy a few of your threads there. hopefully gs treats you well. i havent posted here regularly in about a year.

have you considered a very low boost (7-8psi) turbo setup? i mean you are already in sm at an auto-x event.

suspendedhatch 04-17-2008 12:32 AM

I haven't talked much about things like suspension that don't have to do with mileage cuz I'm not sure people here are interested or that it's relevant. I mentioned that I'm lowered and that's about it.

For suspension I have the Tokico RAK coilovers. Tokico used to be one of the best options years ago. Today there are better struts but that doesn't make these bad. If I were to buy some today or if these ever blow out, I'll probably go with Koni/Ground Control. Yeah I know, that's old news but having seen all the new brands, I still think that combo is still one of the best on a budget.

The upper spring perches were extended 1.5 inches so that the struts have the same piston travel in each direction as if the car wasn't lowered. This also gives me a little bit more suspension travel. At this ride height I've never bottomed the upper wishbone to the strut towers.

I have a Progress 24mm adjustable rear swaybar set to the softer side of medium. On the front I have a stock GSR 24mm swaybar. Poly bushings on each.

I used some high grade washers to space the two pieces of the front lower wishbones to gain some positive caster.

In the front I have a Neuspeed strut brace. Nothing on the rear because I used to have an Autopower 4 pt cage in my old car, but I decided to sell it instead of install it in this car. Anyway I keep telling myself I'm going to learn to weld and then reinforcement seam weld the chassis and skip all the chassis braces.

Then there's the LSD tranny helping accel out of a turn.

My summer wheels are Rota Slipstreams 15x6 with some Kumho Ecsta SPT tires. I bought these when I lived in San Diego, but now that I'm in Salt Lake I plan to have a winter and summer set of tires on different rims rather than one set to handle all weather conditions (not that there's a wide variety of weather in San Diego).

This car was built for street fun (but not street racing) on a budget. For autoX I could use my stock DA or I'd probably find a lightweight RWD car. Maybe an RX7. Maybe a Type R someday. Right now getting a real job and a house is the priority.

There's nothing creative needed for DFCO. If it stalls out at a quick stop, you have to adjust the Decel decay so that it brings back the fuel faster. Or you can increase the cutoff RPM. Mine's at 1100 and it works fine. I think the stock ECU runs it down to 1000 or 1300.

Flywheel feels a lot like stock except for the scraping noise it makes. My girlfriend can drive it w/out any difficulty. I love her cuz she engine brakes. You don't have to launch it or give it any special attention. It's easier to drive than my stock Integra. At just over 11lbs it's not SUPER light. I taught myself how to drive stick only a couple of years ago, and up until a few months ago I was alternating between an auto DX and my standard DA. So on the one hand I don't have a lot of experience with how it should feel. On the other hand I worked at a car audio shop and had to pull in all manner of vehicles in all manner of disrepair. I'm sort of a natural at getting an instant feel for the clutch. When I was shopping for an Integra I was able to drive this guy's car w/a bad tranny better than he was.

Don't waste your money on any piggybacks, controllers, hacks, or chips. Right now there's a guy on the AEM boards in the Honda forums selling his for $700 bucks. If I had the money I would buy it myself and find a car to put it on later. If you're patient and you search hard you can always find someone frustrated with the AEM and having trouble selling it. If it's not allowed then I would personally stick with the stock ECU.

HT like all forums leave a bad taste in my mouth. HT actually isn't as bad as it once was. I poke in occasionally to keep up on new products/ideas and to lend out car security info. Some of these single-cam sites I tried out were extremely elitist. SOHC Honda telling me I need to "get my hands dirty". I use latex gloves thank you. The Team Integra operator is a complete nazi. A lot of the other forums are just dead with no traffic ie G2IC. I like civic-eg a lot but it's pretty dead and pretty low-level. But once it gets popular that's when it all goes downhill. Dumb kids vs forum nazis. Notice you never see any real tuners on forums except when they're promoting products or services.

Turbo... I'm not so sure. It's a good option as you can drive the car w/out boosting and you'll get the same or better mileage. Then you have the power when it's needed. Quiets your exhaust down. But it's a lot of weight and a lot more moving parts. It takes up a lot of space. So I'm up in the air about it. If I had money then Scottie could set me up with something custom and really special. But then SLEEPER would be out the window. I think I'd rather get the Endyn pistons and see if Bisi can make me a cam like he did for topher. According to Scottie, you can get just as much power just as easily with an N/A build. But he says there's a real limit on the D-series when you start talking about real power (300+). I would never want more than 160 at the wheels and I'm sure he'd squeeze out 180.

suspendedhatch 04-17-2008 12:49 AM

Just curious what threads you "enjoyed" at HT. The security threads?

Just throwing out more details as the come to me for anyone who wants to give this project a shot someday.

For the AEM I got a used IBM T40 thinkpad for $360. Windows XP cuz Vista is a joke. I wish the AEM software ran on Mac. Also a Belkin serial to USB adapter. They call it a PDA adapter. And a serial cable of course.

I'm using a 92-95 Civic distributor at the moment. This fits the OBD2 heads perfectly with the same amount of adjustment as the stock OBD2 distributor. And plugs into the stock OBD1 wiring obviously. I've had nothing but problems with the stock coils and cam sensors in all my used distributors. But I will be switching back to DIS in a few days when my parts get here.

I've had Magnecor wires for years now and they are the best hands down. But they become irrelevant when you go distributor-less.

The CBR coils require screw cap spark plugs. NGK doesn't make any. Sadly, the only thing immediately available was Autolite. I'll try to remember to get the part number for future reference. But when these wear out I'll get the Denso's.

I always make my own 8 gauge grounds. I use amp wires but I get them off the roll at an electronics supply shop. I branch a couple off the battery side strut tower. Thermostat, starter housing, tranny. Then I did a 10 gauge from the ground near the passenger's headlight to the tranny ground at the chassis. On the other side I have a wire to the alternator bracket and another to the intake manifold. Then I have a 10 gauge from the valve cover to the core support replacing the factory wire. For the battery I use a 4 gauge. Replacing the 8 gauge to the starter makes for a quicker start up to save gas. I had a 4 gauge going from the trunk mounted battery directly to the starter on my previous car. I have also replaced the alternator power wire a new 8 gauge.

Putting the OBD2 engine in my OBD1 chassis required a couple of small modifications that are covered on my Cause For Alarm EG site, namely the charcoal canister, throttle cable bracket, and IAT sensor.

I ran a wire from the OBD2 engine's knock sensor to the AEM.

Scottie hacked the wires off the crank fluctuation sensor god knows why.

I have an engine mount insert set but I only used it on the AC mount. I had them all in my previous car and didn't want the added vibration on this car.

In my opening post I said I want to outperform the Civic Si but what I really mean is that I want to outperform a hypothetical Civic EG Type R.

That's all I can think of for now. Sorry for the lack of pics. Maybe I'll edit some in later.

thisisntjared 04-17-2008 05:46 PM

yea the security threads. which brings me to an end of my side tangent for a vafc since theives tried again and really screwed up my car this time. i still have my car, but man... i am just sick of them trying. so i have to get rid of the car.

your suspension setup is decent and i admire the rear sway bar. i had an integra front with itr rear and it was just wonderful. i wouldnt get anything but konis(or bilstein) for shocks. from what i have heard, all of those $1000+ coilover kits that are out there do not outperform the koni/gc setup and they cost more. regarding strut bars, i have found that the rear doesnt make a difference, the front upper i am inconclusive about, but the front lower is a definite. there is a subframe brace that integras have but civics dont even though the subframe is the same. this subframe brace on my eg made a noticeable difference on turn-in and i would put that brace in before buying anything else brace related. they are kinda hard to find since nobody knows they are even worth anything. i just picked mine up off a totaled integra i bought and parted out a couple of years ago. by foam or brace, in any eg, the first chasis stiffening should be the front subframe.

I also agree with your sentiments on vista. if i get another computer it will be a mac or it will be running red hat.

Danronian 04-17-2008 06:25 PM

Great project!

I was thinking of installing the y5 into my VX at some point, or installing a somewhat large turbo that would only spool when you really need it in order to have more engine performance but still good daily driving MPG, but I never thought about all the things you're doing to your VX.

I did have an Integra before the VX so I did miss the performance and interior of it. I upgraded to some Del sol seats, and just upgraded the brakes to have hawk pads in the front and a 99 si rear brake setup. Braking is much nicer now, but still without swap bars to help the coilover/agx setup. Maybe someday I'll look into getting a set of Integra ones. Still rolling on the VX wheels but wow, they handle so badly. Might upgrade the wheels some point, but also thinking about just buying an s2k to satisfy my urge to have a somewhat "fast" car.

I wish you luck with the project!

suspendedhatch 04-18-2008 09:59 AM

Feels like I found a new home among the Honda outcasts.

Thanks for reminding me to get a subframe brace. I thought about getting the Megan brace but I wouldn't trust it w/out seeing it in person first. Also it hangs low and looks too JDM'y for my taste. Although not many people should be peeking down there. Then money got tight so I never got around to it.

I looked for a short time for a factory brace and then forgot about it. Is there a big difference in weight and effectiveness of the factory brace vs an aftermarket? Do all the DC's have it?

I had a Skunk2 rear brace but sold it with the DX (this was before I decided to NEVER have anything Skunk2 or JDM on my car). As far as making a difference, with it installed I could park unevenly on a steep driveway and still be able to close my hatch window. Try this out and you'll see what I'm saying. Parked that way with my suspension and swaybars, the car teeters on 3 wheels! I would teeter the car by hand to get a big reaction from my 11 year old. I wasn't sure if the Autopower 4pt made the Skunk2 irrelevant or not, and I had planned to someday get some bars added to it if I could find a respectable offroad shop that didn't look down on Hondas and mistake me for a dumb ricer.

I play with the idea of having Motiva do a stealth turbo for me like they do on the Tundras. They take a brand new Tundra and turbo it w/out any drilling or cutting. Pop the hood and you don't see a thing! You can remove it w/out any trace so the dealership doesn't void your warranty. The turbo is mounted back by the muffler! Yeah I know it would be impossible to run the charge piping on a Honda. But I can dream!

thisisntjared 04-18-2008 02:43 PM

with the turbo back by the muffler the throttle response must be super laggy and i bet the turbo must spool pretty late.

as far as i know, all dcs have the subframe brace since i got mine off of a totalled 94 ls. it mounts on top of the subframe, NOT where the control arms are. your subframe should have two holes on each side of the top of your subframe with the appropriate nuts already tack welded on the inside. i bet the oem peice weighed 2lbs tops, but more like 1lb. anyway, i wouldnt get anything that connected where the front lcas are just because they would have to dip bellow the exhaust and thats just flat out too low and could really ruin the subframe.

suspendedhatch 04-18-2008 09:01 PM

Yeah, being so far downstream the turbo doesn't have the advantage of all the heat that you get when it's mounted right on the exhaust manifold. On a Civic it wouldn't work so well. But it works great on the Tundra.

I just liked the idea of a stealth turbo. I'm going to stay N/A. Since my goal is less than 200hp there's no need for a turbo.

suspendedhatch 04-23-2008 03:48 PM

I got the Integra subframe brace on there today at your request. Took 5 minutes to install. 50% off Wednesdays! It was raining but I found an Integra with no engine so I was sheltered under the hood. I got a bunch of other Random parts including a spare IACV. I got a 94+ fuel filter bracket. The cute Mexican chick didn't know what she was doing and she just charged me $13 for everything!

I don't know why but I have so much more fun bolting Acura parts onto my Civic. I like the sleeper aspect. I feel like I'm installing dealer options that the original owner didn't opt for. OEM parts are higher quality and much cheaper to find used than aftermarket. So far my baby Integra has Integra front seats, an Integra GSR fuel pump, Integra complete suspension and brakes front and rear, an Integra proportioning valve, Integra brake fluid resevoir (91 Civic Si 15/16 brake master cylinder), 96+ Integra charcoal canister, a front GSR swaybar, the Integra front lower brace, and an Integra trunk light. All of this is transparent to most people except enthusiasts with a sharp eye.

I also have a "VTEC-E" valve cover on the way.

My buddy sent me his AEM twin fire, so I'll be doing a nice little write up with pics on how to convert to coil-on-plug ignition using CBR coils and an AEM EMS.

How-To: Convert to Distributor-less Ignition

suspendedhatch 04-23-2008 04:12 PM

I want to see if there's a way I could slice an OEM intake down the center and wrap it around my cold air intake. And then gut the airbox and put it in the stock location as a dummy. But the intake would have to be large diameter and I don't know if maybe there's an Integra intake that will fit or maybe like a CRV intake pipe...

Also I want to get some mounting tabs welded onto my DC header so I could bolt up the factory exhaust manifold heat shield.

This combined with the VTEC-E valve cover and my plan to run multiple resonators should complete the sleeper effect. It's all about the hustle.

thisisntjared 04-23-2008 06:08 PM

did you put the brace on yet? feel a difference on turn-in?

Danronian 04-23-2008 08:06 PM

The OEM VX airbox has a large opening on it, so you could use the larger diameter EX intake arm, and it would fit onto the VX airbox. I'm sure you could fit pipe inside the EX intake arm. I've actually seen a sleeper feature in a magazine already where someone with a civic hid the turbo charge pipe and BOV inside the OEM airbox parts and the turbo under a factory exhaust manifold heat shield.

suspendedhatch 04-23-2008 09:59 PM

I barely just installed the brace today and haven't had cause to put it hard into a corner yet. My tires are **** anyway. But I'm going back to CA in a couple days to get my Integra with the good wheels/tires on it as well as the rest of my tools. Unfortunately I will be renting a car one-way and the VX is going to sit this one out.

I'd be drooling over that sleeper turbo setup. If you remember where you saw it let me know.

Scottie gets paid good money to hide N2O setups. I toy with the idea of having a modest shot of Nitrous tucked away into a fender. Blasting a swapped ricer or a high displacement domestic driver with an inconspicuous single cam would be priceless (at the drag strip of course).

I'm pretty sure my VX intake went into the recycle bin. The LS Integra OEM intake looks to be about the right diameter. But I think that if it was a good fit to the D-series engine you'd see a lot of people running it.

I don't think I ever mentioned that I got the larger Integra Charcoal Canister since I had to convert to the OBD2 style. It slides right into the Civic bracket. The purge control is activated by the AEM EMS.

GasSavers_topher 04-24-2008 08:12 AM


Originally Posted by suspendedhatch (Post 96695)

I also have a "VTEC-E" valve cover on the way.

My buddy sent me his AEM twin fire, so I'll be doing a nice little write up with pics on how to convert to coil-on-plug ignition using CBR coils and an AEM EMS.

Looking forward to it the write-up man sounds awsome. I have my vtec-e valve cover but can't decide how I wan't to paint it. I was thinking something oldschool 40's 50's style but, yet tasteful.

Let me know if you find any advantages of the pencil coils that would be awsome I have thought about them myself but, that would realistically be down the road. Right now in my build I'm just trying to learn and have fun. I see my build almost as a mini-me and obd1 conversion.

As far as the tuning aspect I am doing nothing more than swapping to a p28 that has already has a y5 basemap. Running a wire for vtec and moving a couple of wires for the IACV. Right there is my mini-me and my obd1 conversion in a nut-shell. If you think of anything I missed please inform me.

Also is there any advantage to having a bigger Charcoal canister other than it's size.

If you wan't to hide you N20 set-up you could always put the bottle in the glove box. Or if your frisky and don't use it to often you could put it right where the evaporator for the AC goes if your not using it. The only problem with that is that it's a ***** to get to. If you had a cold air intake running through the stock air box down behing the bumper. You could Easily hide the lines and tuck the into the CAI right in the airbox itsself assuming you using a dry shot.

If you would like me to move my post to my thread and un-clutter yours that's fine.

Glad to see you have some good plans for the vx :TU:

suspendedhatch 04-24-2008 08:52 AM

Nah you're not cluttering up my post. I look at it as a contribution.

If I was going to get the valve cover painted, I'd probably send it to that guy on ebay that does valve cover powder coating. I wonder if he can make it look like the oem crinkle paint.

Let me know if that P28/Y5 base map works. I have a feeling that you're going to have problems. I've looked at Crome and some others and I didn't see anywhere that you could change certain settings like IACV settings for instance. So if you can't change it then I wonder what does it default to? Most likely the original P28 code. And what about VTEC-E? It lets you change the RPM but not the load and tps%, right? So is it going to stay with the original VTEC load and tps? I really don't know that much about it so I'm eager to see what you find out.

I'm not using AEM's pencil coils I'm using the Honda CBR motorcycle coils. AEM didn't release the pencil coils until recently but I've had this conversion for a while now. The only problem is that the MSD box took a dump so I'm borrowing Scottie's Twin Fire. Before this I was using a pair of rotary coils and some custom magnecor wires on my Toyota.

But if you want a recommendation on the pencil coils just ask Bisi.

Advantages of Converting to Distributor-less Ignition
1) get rid of the unreliable distributor 2) less moving/maintenance parts 3) less ignition noise 4) more precise control of ignition timing 5) more complete burn of the fuel mixture 6) allows you to run higher compression, higher boost, and higher RPM

Basically with a distributor, your maintenance parts (cap, rotor, wires) work fine when they're brand new. But every mile you put on them they degrade in performance. Coil on plug ignition is better than brand new distributor ignition and never wears out.

Benefit of CDI Module
Also the use of a CDI not only doubles the volts at the spark plug, but they fire multiple sparks across 20 degrees of crank rotation.

Instead of having a single coil confined to the space inside the distributor, having to fire each cylinder with very little time between ignition events to allow it to charge, you have four individual coils that each fire twice per cylinder and have twice as much time to charge.

The AEM 30-1000 has only two ignition outputs so you have to configure it for waste spark. That means the coils also fire on the exhaust stroke. Any unburned fuel in the mixture gets a second chance. So that should improve emissions. AEM later released the 30-1040 which has 4 ignition outputs allowing a true direct-fire setup. This gives you 4x more charge time per coil than stock, and 2x more charge time per coil than waste-spark.

I don't know if there's any advantage to a larger charcoal canister but I assume it can hold a larger volume.

I was just joking about the N20 idea. But if I wanted to do that then I could take it to the stealth N20 expert. I'd probably use an Edelbrock manifold.

GasSavers_grasshopper 05-05-2008 09:06 PM

You are correct with the DFCO and the RPMs for it are listed in the helms manuals. If I knew how to post images I would, but here is the info taken directly from the manual:

During deceleration with the throttle valve closed, current to the fuel injectors is cut off to improve fuel economy at speeds over the following rpm:
D16Y5 engine (M/T): 850 rpm
D16Y5 engine (CVT), D16Y8 engine (USA M/T): 920 rpm
D16Y8 engine (USA A/T), D16Y7 engine (USA A/T): 910 rpm
D16y8 engine (Canada M/T), D16Y7 engine (Canada): 990 rpm
D16Y8 engine (Canada M/T): 1000 rpm

On a side note, I have the equivalent engine that you have except that I have the correct ecu for the engine. Unfortunately, I got the engine with an automatic intake manifold - meaning I'd have to convert the IACV and EGR wiring.

suspendedhatch 05-06-2008 11:12 AM

Regarding the Above Post
According to a spanish language Helms manual I downloaded, the factory DFCO cutoff for the D15Z7 is 1200 RPM. It also confirms the specs for the other engines as reported by grasshopper. I have been using 900 RPM as my DFCO cut-off and it has worked fine. RPMs don't drop past my idle target when I decelerate. The AEM EMS has a high idle vs VSS and a delay setting that works nicely.

Thanks for that info. I tried looking for the VTEC-E engagement parameters for the Y5 in the Helms but did not see them. They're listed for the Z1 and Z6 in the fifth generation Helms... so I don't know why they skipped over it for the sixth generation.

It should give the

Engine Temp
and for engine load it just says it varies

So is your ECU for automatic or manual? If it's for a manual then you can drill some holes into your intake manifold to allow for a conventional IACV. And you would need a manual trans throttle body.

Where did you get your ECU?

Post up a build thread and link it!

suspendedhatch 05-06-2008 11:31 AM

Up until this point I have been running the stock ignition setup since my MSD DIS4 was bad. The stock coil is bad and I've been using a coil dwell workaround in the mean time which has made the car run decently but with some small problems with idle. My HC's are higher than they should be according to my smog check which I haven't yet passed.

Well I went to California and emptied my garage and brought everything to Utah. I had two spare Honda coils. I tested them with a voltmeter. One was blown, the other had just a hair too much resistance. So I installed it, set the coil dwell to the correct setting, and fired it up. It had a lot of trouble starting up but it ran excellent.

The funny part is that when I took off the distributor cap, there was shredded plastic all over the distributor housing. The little screw worked it's way out of the rotor and spun around scraping the base of the rotor and wedging itself into the cover. One edge of the rotor was bent and burnt looking. Oil is leaking into the distributor so I will have to change the O ring.

The spark plugs were black. #4 was very black and the others were black but with brownish white at the tips. These were NGK's meant for a B16. It's all we had when I did my swap. They are only a few months old but had a couple thousand miles on them. So they're probably the wrong heat range or it's just because I don't have the engine tuned properly.

Scottie lent me his AEM Twin Fire, so I wired it up with the CBR600F4i coils and some Autolite screw cap spark plugs (ugh, I know. But I'll switch to the Denso or NGK Iridiums AFTER I have this thing tuned properly). I had an extremely hard time finding any info on how to wire and configure this to the EMS. My EMS is a 30-1000 box, the oldest box with only 1 extra coil output. So I have to wire it for waste spark, which isn't a bad thing.

I wired the 1&4 in series and the 2&3 in series as per this diagram I found. Started excellent but above 2400 RPM it just breaks up. Makes no power at all. Idles fine as long as the IACV isn't intervening. When it has to intervene, it hunts badly. Tach reading on the cluster is way too low, but seems to be accurate in the EMS? I wired the tach output from the twin fire to the EMS and there was no change.

I tried a couple different combinations of settings in the EMS and nothing changes. I tried changing the spark teeth from 6 to 12 and then 24. I tried ignition tooth 1, 3, 6, 8 at 0, 3, 6, 9 and 0, 6, 12, 18 respectively. I enabled coil 1, 3, 6, and 8. Tried the coil dwell wizard CBR600F4i setting and then the "all CDI except Ford" setting. I turned off coils 6 and 8 and it made no difference.

Then I wired the coils in parallel. 1&4 are sharing power and ground, and 2&3 are sharing a separate power and ground. Blue and Gray are grounded. Still the same. Now it wont even start when I put spark teeth to 12 and ignition teeth to the lower settings.

I'm going to try calling AEM.

suspendedhatch 05-06-2008 09:08 PM

Here's my dyno graph that I forgot to post up.


The blue lines are from the first dyno pull we did. No tuning and no VTEC-E or VTEC engaged. Notice that the torque falls off rapidly starting at 4000 RPM. If you switch to 16 valves around 2500 RPM the graph climbs rapidly all the way past 5000 RPM. This is a point I try to make to people that plan to get a 3 Stage VTEC motor and have VTEC-E and VTEC engage at the same time. The ideal VTEC engagement point isn't until 5500 RPM or so for this motor. If you use a P28 ECU, it activates VTEC at 4800. So you'll have a big dip in torque caused by a late VTEC-E and an early VTEC. Not to mention that the OBD1 D-series maps have much more timing than is optimal for the OBD2 heads which are more efficient and have more quench area.

The first pull resulted in about 65 hp. The second pull (not shown) where the only change was turning both VTEC's on resulted in 110 hp. Tuning netted another 9hp at the peak, but even more impressively it raised the entire graph substantially.

Notice the big dip in power between 5000 and 5500 RPM. This is caused by my ebay CAI. You wont see this with the factory tuned intake. The huge hump starting at 4200 RPM needs to be shifted to the right. If I were to try different lengths and diameters of intake piping I could tune that dip right out. No off-the-shelf intake is going to be optimal for this engine except by coincidence due to its unusual cam.

suspendedhatch 05-06-2008 09:17 PM

Here's what a distributor-less conversion looks like:


This is the how-to article I'm working on. Don't reference this until I've actually worked out all the bugs on mine.


suspendedhatch 05-06-2008 09:19 PM

Here's the VX 13 inch rims vs the HX 14 inch rims



GasSavers_topher 05-07-2008 05:53 AM

Hope you get it all figured out man. Dyno looks good :TU:

suspendedhatch 05-07-2008 01:34 PM

I started a new VTEC-E article: https://www.gassavers.org/showthread.php?t=7282

DRW 05-07-2008 04:49 PM

Thanks for posting the dyno chart. The power looks good. :thumbup: Since the engine is making near peak torque at 2500rpm (91 ft./lbs ) are you able to shift early and keep the rpms low? Or does the car need a few more revs?
How's the mpg?

suspendedhatch 05-07-2008 07:46 PM

Yeah you can shift it early and cruise pretty low. Not VX low... I don't drive that way though. The JDM D15B's love to rev. Especially when paired with a VTEC tranny (shorter gearing) and a 11lb flywheel. I can't help but to blast the RPM's up when I need to get up to speed. It seems like as soon as you give it gas it goes to 4000 RPM. This engine is a lot of fun.

Actually that's how my g/f drives. I have her drive while I tune it on the laptop and I noticed that the way the follow cell moves around the calibration maps is very different than when I'm driving. She shifts early, usually just as the engine is about to make power. Drives me nuts.

The guy that tuned the engine (Scottie) shows off the dyno graph to other D-series drivers. It's very surprising for nearly stock and the torque curve is awesome.

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