VX Intake Questions
 

I have been considering installing a new intake system (such as K&N) for my 1992 VX. Manufacturers claim that this helps the engine breath better, boosting hp while improving mpg at the same time. However, I have not been able to find an intake specifically for the VX (other Civic models galore). Here's my questions:

1. Do the claims of improved mpg and hp hold true for the VX model in particular (does it justify the cost)?

2. Can anyone point me to a website to get the correct intake for my model of Civic? Reusable filter element is a definite plus.

The VX is a great vehicle whose design was way ahead of it's time. However, it's lone glaring flaw is that it is a bit underpowered. A little more hp wouldn't hurt.

The VX does not have a "special" OEM air intake to my knowledge. It is the same for every trim level (CX DX, LX, EX Si) during the 1992 model year.

From what I have seen, the VX uses the same air filter element as other Civics of the same year range. BUT, it has a smaller intake 'arm'. For this second reason, you will have a problem finding a suitable aftermarket intake. But you could probably use a K&N OEM-style pancake filter to get you a little more airflow. And given the meager airflow requirements of the D15Z1, intake restriction is probably not much of a problem.

One more thing. When it comes to acceleration, gearing is hurting the VX more than a lack of HP is. You might look into gear ratios of other D-series transmissions to see if you might be able to build a custom transmission that gives you better gearing for the city, yet keeps the tall fifth gear for efficient freeway cruising. With better gearing for the city, you might even gain some MPGs around town.

Drop-in filter is your best bet. Replacing the entire intake in this situation will most likely hurt your mileage. Most certainly it will hurt your freeway mpg.

At least on more performance oriented Honda motors, intake systems seem to help mileage somewhat. I don't see how it would actually have a negative effect on mileage with a D15Z1. But I can certainly see how it probably would not help power much.

If your engine is hitting high revs alot of the time then the after market air intake might help with mpg, but it will also most likely hurt your low end power because of how fluid dynamics work.
If you think that your vx is under powered then you should ask your self what laws you are braking, I've had 5 adults in my vx merging on to the freeway and felt like it had plenty of power to do whatever I asked of it.
I use a drop in foam air filter and love it, better air flow then paper and catches more dirt then a K&N.

Stick with the OEM intake. I had a short-ram intake with a "high-flow" k&n filter and the car's power wasn't as smooth and it got worse gas mileage.

The VX intake is much narrower than all the other intakes. The whole car is setup to have low RPM power. Low as in being able to cruise at 1000 RPM. The problem with low low RPMs is that there is very little air flow. So you "pinch the hose" so to speak with a smaller intake (it's the same idea with closing one intake valve). When you put an intake on it that was designed for a 16 valve motor you throw the whole setup off balance. The car actually loses power. The D15Z1 with it's 6000 RPM redline never reaches high enough RPM to see any benefit from increasing the intake diameter.

Honda put roller rockers, special low friction piston rings (usually reserved for the Type R only), a lightweight flywheel, an aluminum engine mount and alternator mount, a wideband O2 sensor, as well as a rear diffuser and a front lip spoiler. Honda made a special ECU and tuned the calibration to the bleeding edge (yet they used the same P28 for a D16Z6 and a B16A). Basically Honda put just about as much attention into the VX as they put into the Type-R. And like the Type-R, almost anything you do to try to improve upon it is only going to hurt it.

Actually, it's not that hard to make more HP with a Type-R. I don't know if the same thing applies to MPG and the VX.

Sure, I could pick up some peak hp by removing my intake and unbolting my exhaust, but that would be at the expense of power all throughout the RPM band. Typical bolt-on's only MOVE the power around. Often times it moves the peak of the power band beyond the redline. It's not worth the compromise unless the car is ONLY for racing. In an article I read, the Honda engineer responsible for the Type R in response to a question about people who want to tune the Type R even further said something to the effect of "please don't mess with the car. It's been tuned to perfection." It makes more sense to start with a GSR motor.

The only way to get a significant, consistent, cost-effective improvement in mpg (from the EPA estimate) on a VX is with driving techniques.

Plus guys we're talking about a VX, which was built for exceptional gas mileage, not performance. I would look at a Si if the performance edge is what you want.

I recall a test in one of the import magazines several years back where they basically ran just a small silencer right after the header. The result? Increased power throught the entire RPM range.

What is a "small silencer"?

I agree with you but ->

I'm belgian, I have a Civic VEi (D15Z1 engine).
I have bought this car because I like these Civic, but the others engine are too powerfull for a young driver as me (insurance too expensive).

So I have made some modifications to have more fun when I drive my car.
(K&N intake, D15B7 header, testpipe, D16Z6 midle pipe, Remus muffler, short gearbox).
Ofcourse my gas mileage is worse than before.
But my gas mileage is still better than other Civic (D15B2, D13B2) but with better performances.

A video of my car :

https://px2.sfstatic.com/handlers/Get...d=164040&w=120EG436 (D15Z1) 0-100km/h (3)

(Sorry for my bad english).

By 'small silener', I mean something similar to a resonator.

VEI, I enjoyed your video. It seems to confirm what I read in the service manual, that the VX has a redline of 6300 rpm (the ECU cuts off fuel). And your English is fine.

a vx in belgium is a vei ? very nice. love learning something new everyday!

Yes, VX in America, ETI in Japon, VEi in Europe.

https://hondacar.free.fr/range%20honda.htm

Vx, Vei
 

Whatever the nomenclature or where it was sold, the VX design was way ahead of it's time. People in the U.S. weren't as concerned about fuel economy in the early 1990's like they are today (other places around the world, Europe in particular, did pay attention to fuel economy). Americans are party animals; up until recently they were addicted to big vehicles and wasted fuel like there was no tomorrow-and many still do. Honda has always thought that fuel economy is important, but only now are American drivers realizing the error of their ways. It's a no brainer to state that a modern Civic VX model would sell faster than Honda could make them-and it wouldn't have to use expensive hybrid technologies (batteries, computer controls, etc.)

The irony is that none of the present non-hybrid powered Honda Civic lineup can equal the mileage that the VX attains (I get 46 mpg in mine). The Civic Hybrid comes close, but at a major price premium. Wonder if Honda is doing any research about a new VX-type car?

I'm sure they are (isn't the new version of the CRX a go for production?). The problem is that along with the CRX HF, the VX was an extremely light car (right around 2000 lb). The modern 2d civic with all of it's safety features and crumple zones is pushing 2400lbs. And the 07 Fit is 2390lb!!!

It would really need to shed a lot of weight to get the MPG back up. I don't know what the cd numbers are but the newer civic does look more aerodynamic. I really wish they would bring back a smaller version of the CRX to compete with the smart car.

I like the CRZ concept car (the new CRX, as it is known), and word is that Honda has approved it for production. Here's the link: https://automobiles.honda.com/cr-z/ Nevertheless, it is a hybrid, with all the technology and expense that producing such a vehicle entails. Today's high fuel-efficiency cars come at a cost premium; there seems to be a ceiling at present to how much mpg a pure internal-combustion vehicle can attain: Toyota (Yaris), Honda (Fit), Nissan (Versa), etc. seem to be limited to about 35 mpg or so. To get more than that, you are talking hybrid-and a much higher list price.

The VX is pretty much a bare-bones car, and lacks such amenities as power steering, power windows, power door locks, etc. In light of your weight comparison, the elimination of these amenities would seem to be where some of the reduction came from.

I for one am a big fan of the Fit. I test drove the present model, and loved it. I am really looking forward to the 2009 Fit, which looks to have corrected problems drivers have griped about in the 2007-2008 versions. Nevertheless if I do buy a 2009 Fit, I will sacrifice some mpg in giving up my VX for more creature comfort.

Considering the increased fuel expense involved over the next 200k miles, taxes, insurance, and resale my VX is worth more than a new FIT right now.

If I want a clock, I check my cell phone.
If I want a radio, I'll buy a small portable at Wally World than I can plug into my lighter socket.
No power steering leaks, no busted power window regulators or motors, no power door lock failures.

I believe the VX would pass current 50 state emissions with the new fuel with less sulpher and 10% alcohol.

Its truly a shame they didn't refine it for 15 years. Think of how good it could be now.

regards
gary

VERY well put. I agree 100%.

Until a Fit gets well over 50 MPG it won't be a worthwhile economical upgrade for my $2k VX. I'll wait till I find a cheap Insight to sell off the VX. :thumbup:

The main barrier to lean-burn has been emissions. Lean mixtures create very high NOx emissions. I found an article where they have just discovered a way to improve catalysts making clean lean-burn engines possible.

https://www.sciencedaily.com/releases...0222095427.htm

I use my VX to do pizza delivery (it is my only job at present)- a lot of stop and go driving, and it's pretty hard on the car. Many things are wearing out on the old ride now. Here's what I've changed out in the last year or two, in no particular order (most of the work done by yours truly):

1. New front brake calipers and rotors.
2. New master brake cylinder.
3. New LAF sensor.
4. New hatch struts.
5. New clutch.
6. New CV boots.

And here is what still needs to be done:

1. Center exhaust pipe needs replacement - has hole near the muffler.
2. Door lock latches need replacement - can't lock the car from the inside.
3. Rear brake job, replace both drums.
4. Rough idle/puffing. Probably needs EACV replacement, or maybe just the EACV filter-which is next on the agenda.

Of course, the cost of all this work still comes out to a lot less than buying a new car. I also don't have to worry about paying for comprehensive insurance - I only do liability right now.

I'm gonna go out on a limb here and guess you might not have owned many honda's, if so then i apologizes...but i have seen this mentioned by people before and its not broken its how it was designed...Honda made a little trick to help prevent you from locking your keys in the car...when you try and lock the door from the inside on the drivers side try pulling the handle out and then pushing the door lock...better description hold the door hand on the inside like you are opening the door, while you are holding it you can lock the door...HTH

[QUOTE=Loserkidwac;110966]I'm gonna go out on a limb here and guess you might not have owned many honda's, if so then i apologizes

I have owned several Hondas, and am aware of the design feature you mention to keep you from locking yourself out of the car (this only applies on the driver's side door). In this case, the lock buttons on both doors are broken, and this is why the doors can only be locked with the key from the outside.

The lock buttons are not available as an individual item; in order to fix the problem I will have to buy and replace both inside assemblies. I seem to recall these are about $35 each from online OEM Honda parts dealers. I'll get to it eventually...