Let see if this is a little more tech.

Have you guys worked with your fuel pressure. I highly recomend it since we have seen around 6 HP gain playing with the Fuel Press Regulator on Pepe's car. I am using now the AFC-V from Apex. It handles fuel and Vtec point too. We have learned that the way to go is to lean the mixture a little. ( around the lowest psi setting on the service manual)

 

I actually have played with fuel pressure, although I tried richening it when I had my headers on the car. It felt very slightly faster after some tweaking, but the milage went down to about 11 mpg. As for leaning it out, I don't recommend that. Fuel helps cool the engine. Leaner runs hotter and can lead to severe problems. I just checked my plugs yesterday when I did my compression test and they look perfect - black, but not too bad, which means the car runs just slightly rich. This is the best setup for longevity. I recommend not leaning it out.

 

Reverend,
We use the lowest setting that the service manual said our cars should have, so we should be OK there. The manual says that the factory FPR has a range like 7 PSI difference. This is for example one S2K may have 40PSI and another have 47PSI from factory. In my opinion that's a huge gap!

 

I agree, that should be fine. But as a general rule, remember that leaner will often make more power but will lead to shorter engine life.

 

[QUOTE]Originally posted by The Reverend
[B]I agree, that should be fine.

 

atmospheric conditions have an effect on all this as well, i noticed a difference when i increased fuel pressure in the cold.

 

I posted the results of my experiments some time ago. Testing by timing WOT acceleration from one rpm to another in third gear I found that the real lean settings (43-46) were not as good in the cold weather we are having. I wound up with a higher setting, but still at the lower end of the stock spec (49 in a 47

 

I dont have a dyno, but with mine set at 42 psi/about 97 octane seems to run pretty good, I think thats a collective gain though.

For many reasons, cars usually come from the factory running rich, with mine set at 42 I have been checking the plugs very often and also with temp changes. They look just fine, very clean with a slight brownish haze, no itty bitty specs from detonation.

 

Brownish haze means you're plugs are too cold for the motor.

Cars come from the factory running rich because it is safer and motors last longer.

 

then its ready for boost! They arnt THAT brown, very very slight. The tannish-brown is the perfect read off those plugs, Stock plugs are right where they should be.

The richer factory settings are for a margine of error/safety/longevity yes, but thats because not all engines are the same off the factory floor AND not all driving enviroments are going to be the same(oh yeah not all gas is good either) all over the world. Tweaking your car can yeild great results.



[Edited by cmnsnse on 01-17-2001 at 09:40 AM]