I've recently added long tube headers and blackwing to my 2001 A4 coupe with 2.73 gears. I've purchased a 7198 Predator rev 9r09. I've read several posts on tuning for fuel and timing. I've data logged for my 'ltft'. I was coming up with a average of +5.47 on a 20 mile cruise on the interstate with throttle at 20% and 1900 rpm. I then changed my injector slope to -6. Now I'm running at -.78 to -1.56 while cruising and it goes to 0 at WOT...which is perfect. Next, I checked my spark advance and O2 mv at WOT. At WOT, I'm getting 25.50 for spark advance and .90 mv at the O2 sensors. From what I've seen, I should be around .93 mv with long tube headers. What should I adjust next? I've seen some posts from, I believe 06MONTECARLOSS(Lew), to add +6 to my PE since I went -6 on my injector slope. Will this bring my O2 mv to .93? When I adjust the timing, mine has three different rpm ranges to modify. Do I add 1 degree at a time to each rpm range. I guess my 7198 rev 9r09 doesn't go by % advance...it goes up 1 degree at a time. I know I looking to be around 28-29 degrees and a being at 25.50, I can go up 2-3 degrees. I'm watching 'maximum knock' because I don't see one called knock retard. My maximum knock is at 0. Can anyone give me some advice on getting me where I need to be. Thanks in advance.
Thanks. Last night, I added +2% to the PE fueling. Went out for a ride and noticed the O2 v dropped slightly to .89-.90v. Now I realize that I'm going the wrong way. So, until I get a data cable, you'd leave the PE set at 0.
What about setting timing at the three different rpm ranges? Would you increase those 1 degree at a time for each range or just for WOT 4-7K? Let me know. Thanks.
I would leave the timing alone... the diablo tunes already have the timing pretty jacked up compared to stock...
as an fyi, in all the custom tunes I do, normally I actually have to pull out/reduce the timing in certain spots in the tunes to reduce/eliminate some slight KR people have....
so yeah, I wouldn't add any more timing to it...
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2006 Monte Carlo SS -- CAI, Poly mounts, STB's, FM Super 40's, Custom DiabLew Tune! Email: 06MonteSS@diablewtune.com
I would leave the timing alone... the diablo tunes already have the timing pretty jacked up compared to stock...
as an fyi, in all the custom tunes I do, normally I actually have to pull out/reduce the timing in certain spots in the tunes to reduce/eliminate some slight KR people have....
so yeah, I wouldn't add any more timing to it...
I agree---a stock PE AFR is usually in the mid 11 range -so when you lean it down to a 12. to 12.8 range you may get some KR even with stock timing---
Another thing--Is the 25.50 timing the commanded or asked for timing ? or the actual timing ? There are timing subtractions for IAT temps and ECT temps that will change the commanded time--typically you can remove most of the deducts up to a point so your commnded timing will match your actual---this makes it easier and more accurate to tune---Also--28* seems like an aweful lot of timing for a daily driver type car--If indeed that is your actual timing--These LS heads are so efficient they don't need a ton of timing to make HP- some engines run as low as 19*and make the best power/tq there---My LS1 with 243 heads runs best with 22-24* at a wide band checked 12.8-1
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Predator tuning with long tube headers
