This weekend I plan to tackle my rich running condition and to do that I am using an auto x ray as the scanner and a MAFT+ as the tuner. at this point i dont need to adjust my spark advance so my first question is this..

On the MAFT+, do the wires that are used for the spark advance have to be hooked up in order for the unit to work correctly or can a person just leave them disconnected for the time being and just adjust the fuel.

also, what all do i need to take into consideration when adjusting fuel? (long term fuel, short term, O2?)

 

you can use MAFT+ without the timing portion being set up. You look at the LTFT after the car is fully warmed up at idle in fuel trim cell 16. If the LTFT are indicating your running rich, run the math as to what % rich or lean your running, and set the MAFT+ to compensate for what you need. As you drive the car in other fuel trim cells, the PCM will lean for your base setting. For WOT fuel settings it's tougher. I know guys use the O2's but I'm sorry, that is not the proper way to do it unless you have a wideband. I had the experience, that my O2's were reading 930mv at WOT and the wideband said i was at 14.2:1! Way too lean. we richened it up to 12.5:1 and my O2's still showed 930mv at WOT. simular experience with my other motor except it was running factory rich and when we leaned it out, no difference in the WOT O2 mv readings. Let's assume you are running rich at idle. once you've adjusted your idle base setting and drive the car for awhile, the PCM at WOT will lean out some. the factory set up for the WOT air fuel ratio is 11.7:1. this may actually go to 11.9- 12.0:1 "ISH" after you lean out the idle. I know alot of guys like 13-13.5:1 or so at WOT. My limited experience on 2 engines was, we were on the edge of detonation at those levels. For safety, we went with 12.5:1 on both engines. One actually produced more rwhp at the richer setting the other was only 7 rwhp more at the leaner setting but there was no margin of error for 93 octane gas. At WOT throttle you can lean the setting 2-5% AND PRODUCE GOD POWER AND be on the safeside. good luck!

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'97SS, More Performance 396, AS&M cold air, Grotyohann LT, SLP 2ODL muffler, Magnacor, PCMFORLESS PCM, LS1 twin piston calipers, KVR crossdrilled and coated rotors, SLP stage II w/ KYB AGX, 6M, Star Stage II.

 

cool. anyone wanna help a tuning dummy and explain everything i need to do?

[This message has been edited by dasmoothtalka (edited August 29, 2002).]