I have a GSR motor in a 95 hatch. I decided to put it on the dyno, and when I looked at the graph it was running very lean in the midrange from 3000-6500 it's waayyy lean like 14.5:1, then from 6500 to 8000 it's perfect at 12.0:1, and from idle to 3000 it's seemed to be perfect even though the car was never put full throttle on the dyno at idle.

The air fuel chart looks like a stretched out dome. Why would a nearly stock motor run so lean? I have i/e/h and a skunk2 intake manifold. I tried new fuel filter, and I have a STR fuel rail. Could the rail cause my car to run lean???? I didn't think so, but maybe. I'm also running about 16 degrees of timing, on a stock obd1 p72.

On the dyno I had the distributor advanced, but I only had 16 degrees of timing, because of a CEL for a AIT sensor (i assume that's a driveability code that retards timing, and makes the car run rich) Does that mean that when I fix the CEL the car will run even leaner with the more timing, and leaner fuel maps??

Did my 4 bolton's add so much air, that the motor needs to be tuned? Is is that simple? If so, I guess I gotta order some tuning parts. Atleast a FPR for now, but ill order Hondata eventually, cus I bought some JunIII cams, Jun valveprings, Jun retainers, Jun cam gears, and b16 pistons...So when I throw that all in there, Ill tune it with hondata. Hoping to make atleast 190whp.

Is it unsafe to run my car the way it is right now. I've been ragging on it for like 50k miles, running that lean, and I never even thought that it was lean. Even with snow white plugs, I always thought it was from occasionally running 110 leaded. I didn't believe a stock motor with stock ecu would run lean...rich yes, lean, i didn't think.

 

13 hits and not one reply? Comeon guys, help me out..


TTT! (this forum moves pretty fast!)

 

It might have to do with having a Skunk2 manifold. The stock GSR on is a dual stage with a certain flow characteristic.

 

Get the CEL fixed..., set the timming back to stock. Then take it the dyno again (if posssiable), and from there start playing with it. I would not trust any kind of readings, from an engine/ECU throwing a CEL of that kind.

Just my thoughts...


[Modified by 88_SC_CRX_Si, 6:49 AM 6/26/2002]

 

You are running the Skunk2 mani... did you diable the dual stage from the stock mani ? Which codes is the ECU actually throwing ?

X2

 

3k-6500 before you get to the secondary x-over, might be where you're sucking in more air than the computer knows because of the SK2. After that, all is well when the computer adds fuel because it thinks the secondaries are open. Maybe I'm wrong. Will reseting the ecu help? How do you disable the dual stage from the stock manifold? Through the ecu?


[Modified by speedymon, 11:20 AM 6/26/2002]

 

take a FPR and VAFC to it asap. at least you found the areas you are running lean in and you can drop more fuel in it using the VAFC. change the ECU if you can to a JDM b16 with no rev limit and stock timing.

 

I'm gonna get a b16 obd1 ecu, and raise the fuel pressure like 3psi with a fpr...and then check the plugs out. See what they look like. Right now, they are WHITE like snow.

They check engine light is for a broken AIT sensor. I forget the code name.