[good question] 
Tune for power
Originally Posted by Frost
... At the end of the day, a new guy (to RPM) had a 99 formula with a lid, LTs and true-duals. He wasn't tuning, just pulling. The first pull, the AFR was a dead-*** straight line at 12.9ish :1... 6spd dynojet, 345RWHP if I remember correctly. The car had a factory tune 
Being a 99, I think you'd be lucky to find more than 8 in timing, but it may like a slightly leaner AFR.... Point being, after that pull, it's not a sure thing to see past 10rwhp. This car is an exception to the rule for the MOST part though.
Being a 99, I think you'd be lucky to find more than 8 in timing, but it may like a slightly leaner AFR.... Point being, after that pull, it's not a sure thing to see past 10rwhp. This car is an exception to the rule for the MOST part though.
... until he drove it and part throttle/response was much improved. 
Originally Posted by rickssz
Just tryin to learn and my car was running lean and I was told that was bad and setting off knock. I then assumed headed toward rich was good and enabled the timing to be advanced.
Rich will allow/require higher, or more advanced timing because the denser fuel mixture has a slower burn rate. Therefore, finding the optimal point of ignition will require the spark to fire sooner. So, in a sense you're retarding the timing indirectly by running a richer mixture.
The truth is, you want the optimal mixture and the optimal timing together. To get there, you need a WBO2 and a dyno...plain and simple.
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SSpdDmon
Thats what my guy was doing he kept dropping AFR 14 to 13 to 12 etc which I thought was getting richer. I could see the AFR on the dyno screen but he wouldnt give me any timing specs. He said WOT timing didnt actually show on the screen but he could figure it out or calculate it. He was using HPtuners.
Thats what my guy was doing he kept dropping AFR 14 to 13 to 12 etc which I thought was getting richer. I could see the AFR on the dyno screen but he wouldnt give me any timing specs. He said WOT timing didnt actually show on the screen but he could figure it out or calculate it. He was using HPtuners.
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Originally Posted by edcmat-l1
Rarely do I see factory cals very close at all at WOT. Usually they are all 11.3-11.5. If they are any leaner than that with an OE MAF, I'm checking for MAF contamination.
Sometimes an aftermarket MAF turns out to be kinda lean at WOT, but they end up needing recalibrating anyways.
Most of the gains on stock or bolt on cars average 15-20 RWHP pretty consistently.
I've had to work hard for 14 or 15 on some, and then others will nail 20 or more real easily. I have seen gains of up to 25 on header cars.
Sometimes an aftermarket MAF turns out to be kinda lean at WOT, but they end up needing recalibrating anyways.
Most of the gains on stock or bolt on cars average 15-20 RWHP pretty consistently.
I've had to work hard for 14 or 15 on some, and then others will nail 20 or more real easily. I have seen gains of up to 25 on header cars.
Ideally, you want to be between 12.5:1 and 13.0:1. Yes, lower ratios are richer and higher are leaner. Do you remember where you ended up? Did he change the timing at all? Or would he completely not say a word? Either way, it sounds slightly shady. If he's working on my car and I ask what he's doing to the timing, he best be telling me or he's not getting my money, I'm taking the keys, and I'm out.
Originally Posted by rickssz
Edcmat
I thought afr in 11's was rich and 13/14 headed toward lean?
I thought afr in 11's was rich and 13/14 headed toward lean?
Your tuner should be willing to show you what he has done. At least show you something like the timing table.
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SSpd
Dyno says he started at 13.0 to 13.7 low to high rpm.
Finished with 12.4 to 12.9 low to high rpm.
He said he made some timing changes but didnt reveal any timing specs. He did say it didnt knock anymore but I dont know if the increased richness stopped the knock or if he just retarded total timing???
Dyno says he started at 13.0 to 13.7 low to high rpm.
Finished with 12.4 to 12.9 low to high rpm.
He said he made some timing changes but didnt reveal any timing specs. He did say it didnt knock anymore but I dont know if the increased richness stopped the knock or if he just retarded total timing???
AFR is in a 'respectable' range. Ideally, a slightly richer AFR (in theory) makes for better torque numbers. I've never had the opportunity to play around with this on a dyno though. I'm most curious about the timing. For example, I could bump my '02 A4 up to ~22* prior to peak torque, but could only run 18* at peak torque before ending up around 23* at peak power. The pre-'01 cars are quite a bit different though as they come with anywhere from 23*~29* of WOT timing above 2200rpm from the factory. Really, the only sure way to tell is to make a couple different pulls on the dyno to see what the car likes. If he just adjusted AFR and then said, "Hmmm...no KR - I can call it quits," then there may be some left. If he said, I wonder how it likes 22* vs 24* vs 26* at this AFR, then I'd say you're not going to find any more HP hiding in there.
Originally Posted by rickssz
Dmon
Thanks for the feedback it def helps. Hey your 02 timing question was that with torque management active or deleted?
Thanks for the feedback it def helps. Hey your 02 timing question was that with torque management active or deleted?
I only ran 50% torque management on that car because of the stall. But, that shouldn't matter during WOT...just during WOT upshifts.
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I hate to dig up this thread but....... Im about to get my car re-tuned friday and need to verify a few things. I originaly got tuned about 3-4 weeks ago. The car baselined 326/338 SAE (cutout open w/ all mods in sig). The AFR was at 13.5-13.6. He lowered it to 13.0-13.1 and found 6 more peak hp and 13 more peak tq (332/351). He said, if i remember correctly, the timing looks ok and there is no knock retard. He felt pretty sure that was all he was gonna get. The numbers after the tune were significantly higher in the lower rpms, and not so much up top. The next day I realized I had a loose spark plug, so loose it was ticking like an exhaust leak (you could grab it and move it around in the hole, really wobbly). I then read on here that if your AFR is higher than 13.0 you probably have a dirty maf. So i cleaned that as well. After all this i decided I should get tuned again. I want to go in there a little more educated this time.
Ok, so from what i've gathered so far in this thread, I shouldn't gain much from the tune since I was already pretty lean. However, my maf might have been throwing off the afr, correct? If I go in and dyno the same ~332 with the same 13.05 afr, what should i do to find more power? With all my mods I should be making atleast 340, I think we can all agree on that.
Thanks guys...
Ok, so from what i've gathered so far in this thread, I shouldn't gain much from the tune since I was already pretty lean. However, my maf might have been throwing off the afr, correct? If I go in and dyno the same ~332 with the same 13.05 afr, what should i do to find more power? With all my mods I should be making atleast 340, I think we can all agree on that.
Thanks guys...
Last edited by TLUZLS1; Aug 8, 2007 at 09:05 AM.
I have gained between 4fwhp and 150 rwhp on stock vehicles with a tune.
All depends on the vehicle.
Stock focus picked up 4 fwhp, and a stock 6.0 diesel, will pick up 150 rwhp.
most lsx gain about 10-15 rwhp on average, some only pickup 5-7
Ryan
All depends on the vehicle.
Stock focus picked up 4 fwhp, and a stock 6.0 diesel, will pick up 150 rwhp.
most lsx gain about 10-15 rwhp on average, some only pickup 5-7
Ryan
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How would the dirty MAF and loose spark plug come into play? If my AFR was ~13.55 then that was because of the MAF right? Was I loosing any hp from the loose spark plug?
