My New N/A Del Sol Project
 

I started out with a D16Z6 turbo engine that is built to handle 600whp and still get great FE. This engine is now in my Son's Honda Civic. I'm still working on it but I decided to try to build an engine for the Del Sol that could easily be duplicated. So that brings me to my 3rd engine setup.

Car 1994 Del Sol
Curb Weight 2295lbs
Engine Stock D15 1.5L non-vtec
Transmission VX manual 5 speed

Body Mods:
Lowered 2 1/2 inches H&R Race springs
1995 smooth front bumper without fog lights
Adjustable lexan front grill block
VX Wheels with LRR tires
Custom Built rear window step

Engine Mods:
WAI
P28 ECU w/CROME PRO Engine Management
Innovate LMA-1/Aux. Box-3 Wideband O2

Goals:
70MPG @ 65MPH Freeway driving
50MPG City driving
Easy to duplicate for around 7000k

My personal best with this N/A 1.5L engine setup has been 68MPG freeway @ 65MPH avg. This was done running a airfuel ratio of 17.5:1

I don't think I can get over 70mpg with this setup in N/A form. Its max out after reviewing the data:(

I saw the target(?) A/F ratios in your gas log.
Any adverse (short and long term) effects (high oil temps/high EGT temps/etc.)?

I am using a chipped P28 on my Z1 (no wide band sensor).
How have you adjusted your timing maps to work in the higher A/F ratios?

Good luck!
:thumbup:

I'd say one of your biggest hurdles to that level of MPG would be the aerodynamic nightmare that is the rear deck/notchback window.

It may look really nice, but it is horrifying what that does to the airflow. You might be best off creating your own slantback out of lexan or plexiglass, to try to smooth that turbulent void. Make it look like an old CRX in profile, rather than the pseudo-convertible that is the Del Sol.

Thank You!

No short term effects to date. Long term still unknown. I need to put more miles on both engines to see if there is any damage.

The water temps actually drop a small amount when running in lean mode as do the oil temps. EGT drops a ton in lean burn mode also. My timing maps are running way more ign. advance when in lean mode combined with very light load. When at light load climbing a slight hill the A/F ratio drops down to 15.0 with closer to a stock ign. advance.

Timing is adjusted on this engine with CROME running a Moates Ostrich so I can have real time programing. On my Neptune system it has RTP also. I love Neptune its a killer software for the money!!

Have you ever considered running with RTP instead of a chip?

You Got that right. LOL

I actually had crash wrap at one time to see what it would do to help the rear window area.
https://www.fuelly.com/attachments/fo...dce0a389b3.jpg

https://www.fuelly.com/attachments/fo...e5c4bcb39a.jpg

But its my wife's car now so I had to compromise with a rear window step instead.

wow the delsol would have made a great coupe

Yeah... It was "Officially" the CRX Del Sol, but they really should have sold, side by side, the CRX and then the CRX Del Sol.

A hatchback with those modern clean lines...

Can you imagine what it would have been like to have such an amazing MPG car as the factory tuned 1995 CRX VX?

They could have easily beaten the Metro XFI and become the most fuel efficient gasoline car ever made.

It sure would of made a killer car.:thumbup:

Re: My New N/A Del Sol Project
 

Update:

I got most of the body work done this weekend. The passenger side rear quarter had a fairly decent dent that took some work but she's all straight now.

I did pick up a sponser today.:thumbup:
PPG is going to sponser all my paint supplies so this will save me some major money.

I'm going with PPG's "Envirobase High Performance" system. This is a water base system that is the future for automotive refinish. This is all part of the going "green program". Several tons of VOC's(Volatile Organic Compounds) are pump into our air from body shop's today. Water Born paint systems reduce these amounts significantly.

So not only will the Del Sol have a much better FE over stock but it will also have a new paint job that's environmentally friendly.

Re: My New N/A Del Sol Project
 

I found a nice "loop road" where I can test my car at 45mph non stop. I'm setting up to have an extra driver to run the second leg with three legs total. Its going to be several hours of driving. These roads are very hard to find!!!

My plan is to drain all the fuel out of the car. Add 10 gallons and run it until its out. Record mileage. I will have an extra 2 gallons with me in the trunk to get me home, at the most only 10 miles.

Then I will do the freeway test the same way at 65 mph.