Well im getting ready to hit the dyno this tuesday. I just wanted to know what to look for and what i want to achieve. Which functions to use on the VAFC to get my a/f ratio as nice as possible. If im correct i use my cartech FMU and AEM FPR to richen the car up and then use the vafc to lean her out right? Schwett
your old setup was similar to mine now, what should i be looking for and any tips? Thanks a lot guys!
Last edited by preludesh01201; 07-22-2004 at 09:43 PM.
Yup, ordered some new plugs. The J&S is picking up some knock near 6 clicks and i have 93 over here so whats a good gap i should try this time. Ive been runing the 1 step colder NGK's.
As far as tuning, you are going to want to use the VAFC only for setting vtec and fine tuning the fuel curve. Set the Car Tech FMU as close to your target a/f as possible.
Originally posted by sharkcohen As far as tuning, you are going to want to use the VAFC only for setting vtec and fine tuning the fuel curve. Set the Car Tech FMU as close to your target a/f as possible.
^^^ what he said.
more specifically, tune with the cartech until you are looking at 12.0:1 at the leanest part of the curve. adjust your idle pressure with the aem if necessary after doing so but before VAFC tuning, as changing the cartech atmospheric pressure setting can affect the fuel pressure at full vacuum is well. you want to have both the FPR and FMU in a reasonable approximation of 'good tune' before going in with the vafc. use the vafc to lean it out a bit across the board until you get something like 12.5:1 or maybe a bit leaner up until the top end, and let it richen out a bit to 12.0:1 or so at the fuel cut.
Well theres the dyno. Didnt get what i was hoping for but not bad. I must achieve 225-235. Any suggestions?
The picture is too small... I can't read that. I even tried d/ling it and blowing it up... is that 214 whp?
I'm no expert, but shouldn't that power curve up top be alot smoother than that? It looks like it takes a nosedive at between 6k and 7k RPM's. I think it should look more like this:
I'd be more concerned with the extreme jagginess of the curve above 6k rpm than the max power at this point. Was your belt slipping? Was the J&S pulling timing for knock up there? Were your plugs new? What were they gapped at? What are the conditions your cap, rotor, and wires?
Well up top my J&S was pulling timing here and there. A few runs it did and a few it didnt. Im thinking it wasnt good gas because plugs were brand new just installed at the dyno gapped at .028 with new wires and distributor and cap are stock with the car only having 9888 miles on it. As for the belt we tightened it and it had a gain. Im gonna try some things and take another trip up there, im hoping it was the belt or bad fuel but we'll see. Hows the air fuel look?
Im wondering what to do to improve the power and top range. What could cause the power to be lower. The best at 4 clicks was 205 and at 2 clicks was 212 on 93 octane. Im not blowing any white smoke and the engine only has about 9888 miles on it so everything should be good. What to try and what to do? Any suggestions?
Again, I'd be less concerned about your peak numbers right now and more concerned about the issue you are having above 6k rpm, as shown in the curves. It's either a slipping belt, an ignition issue, or your J&S pulling timing for knock. Fix this issue, then worry about numbers.
Your a/f in the high end looks fine. A bit lean in the low end for WOT for my taste.
What do you recommend i do to correct these issues. I had new plugs in so thats ruled out. I threw a new belt on and im gonna get the gatorback belt soon. Any other suggestions?
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