Especially on street tires. Now, how can I do this to my car? 
A6 Launch Timing issue
Drifting
Joined: Jun 2002
Posts: 1,682
Likes: 3
High and low octane advance tables for one. I few other areas had to be tweaked but those were the two tables had the biggest changes.
Basically when you go full throttle there is a spike in air volume which causes the PCM to use a considerably lower advance (i.e. 0*) as commanded in the High/Low Octane tables.
Also, I never thought it was an issue until I decided to use the logging feature with HPT. I had already disabled TM through with the normal switches built into HPT. The car felt great after that change but I noticed I was getting hardly any wheel spin at that track during launch. I know the track is sticky but I figured I should be able to spin a little off the line considering my car spins pretty good on the 1-2 shift and chirps the 2-3. Well after the logging on Friday, I see why I was not spinning at launch. It had to do with the timing advance issue.
Basically when you go full throttle there is a spike in air volume which causes the PCM to use a considerably lower advance (i.e. 0*) as commanded in the High/Low Octane tables.
Also, I never thought it was an issue until I decided to use the logging feature with HPT. I had already disabled TM through with the normal switches built into HPT. The car felt great after that change but I noticed I was getting hardly any wheel spin at that track during launch. I know the track is sticky but I figured I should be able to spin a little off the line considering my car spins pretty good on the 1-2 shift and chirps the 2-3. Well after the logging on Friday, I see why I was not spinning at launch. It had to do with the timing advance issue.
Thread Starter
ZO6 Owner
Joined: Nov 2007
Posts: 979
Likes: 5
From: Richmond Texas
Thread Starter
ZO6 Owner
Joined: Nov 2007
Posts: 979
Likes: 5
From: Richmond Texas
Ok guys, here are the results...IT WORKS!!!!!
I didn't set any personal records tonight as far as ET (caused by new traction problems
) but I did see a lower 60' time even with the added spin off the line (I have a video). I tweaked Bill's tune a little bit and the graph shows the improvement.
Mods: Vararam, Corsa Extreme, TM removed (with launch fix)
Tires: Base GY Run Flats
Here are the stats from my best run:
60' 1.9138
330' 5.2739
1/8 MPH 90.34
1/8 ET 7.9806
1000 ET 10.2877
1/4 MPH 116.52
1/4 ET 12.2303
DA: +80
I didn't set any personal records tonight as far as ET (caused by new traction problems
) but I did see a lower 60' time even with the added spin off the line (I have a video). I tweaked Bill's tune a little bit and the graph shows the improvement.Mods: Vararam, Corsa Extreme, TM removed (with launch fix)
Tires: Base GY Run Flats
Here are the stats from my best run:
60' 1.9138
330' 5.2739
1/8 MPH 90.34
1/8 ET 7.9806
1000 ET 10.2877
1/4 MPH 116.52
1/4 ET 12.2303
DA: +80
Last edited by n77nxc; Mar 20, 2008 at 12:16 AM.
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Thread Starter
ZO6 Owner
Joined: Nov 2007
Posts: 979
Likes: 5
From: Richmond Texas
Dude, too bad you couldn't make it out. I really would have like to use the M/T's. You know Sealy isn't the best prepared surface and I was spinning at launch and between shifts. The M/T's would have been a BIG help. It was super packed last night...a total of 8 cars the whole night. 
Race Director
Joined: Mar 2007
Posts: 11,331
Likes: 18
From: Missouri City Texas
Yeah, sealy is tough to run at on street tires because you can't get aroudn the water box.
I'll be out next wednesday for sure...if you want to go out we'll put the MT's on your car for a pass.
I'll be out next wednesday for sure...if you want to go out we'll put the MT's on your car for a pass.
Le Mans Master
Joined: Feb 2006
Posts: 5,762
Likes: 4
From: Chandler Arizona
Ok guys, here are the results...IT WORKS!!!!!
I didn't set any personal records tonight as far as ET (caused by new traction problems ) but I did see a lower 60' time even with the added spin off the line (I have a video). I tweaked Bill's tune a little bit and the graph shows the improvement.
Mods: Vararam, Corsa Extreme, TM removed (with launch fix)
Tires: Base GY Run Flats
Here are the stats from my best run:
60' 1.9138
330' 5.2739
1/8 MPH 90.34
1/8 ET 7.9806
1000 ET 10.2877
1/4 MPH 116.52
1/4 ET 12.2303
DA: +80
I didn't set any personal records tonight as far as ET (caused by new traction problems
) but I did see a lower 60' time even with the added spin off the line (I have a video). I tweaked Bill's tune a little bit and the graph shows the improvement.Mods: Vararam, Corsa Extreme, TM removed (with launch fix)
Tires: Base GY Run Flats
Here are the stats from my best run:
60' 1.9138
330' 5.2739
1/8 MPH 90.34
1/8 ET 7.9806
1000 ET 10.2877
1/4 MPH 116.52
1/4 ET 12.2303
DA: +80
Race Director
Joined: Mar 2005
Posts: 11,549
Likes: 27
From: Southampton NJ
you say it works you get a better 60ft with tire spin but no better et
so were did you go wrong
Race Director
Joined: Mar 2005
Posts: 11,549
Likes: 27
From: Southampton NJ
humidity could account for the spin resulting in less tm being invoked, but if the 60 ft is better the et shold be better, the 60 ft should compensate for the humidity, but if the humidity was 30 % before to 70% now it doesnt change the da that much, and could show no diference. if temp was colder or bp higher or both, humidity is not that big a factor i live in a state were it is humid most the time. typicaly 60 ft picksup you et better, but with tm it doesnt it actully comes in further down the run. when i see consistant 60 fts better than mine, then i will believe. not as good but better, because i still have tm
Thread Starter
ZO6 Owner
Joined: Nov 2007
Posts: 979
Likes: 5
From: Richmond Texas
" with no further information.I on the other hand have been forthcoming with information to individuals that have asked how to remove the dip. I have nothing to hide.
As far as my ET is concerned, I was getting a lot of spin between shifts. The track I was at is not nearly as good as Houston Raceway Park.
Futhermore, to fix the dip, you have to increase timing advance in the high and low octane tables. I'll post screenshots of my tables later tonight so you can see where the timing was added.
Its amazing how I try to post a fix on an ongoing issue and get called out about my ET. WTF?? When I say it worked...did you not notice the timing advance did not drop to 0* at launch??? Who cares if my ET wasn't faster.
Race Director
Joined: Mar 2005
Posts: 11,549
Likes: 27
From: Southampton NJ
You know this is a pretty smart a$$ comment coming from someone that didn't even reply to my post asking you what you did to resolve the issue. You arrogantly said "some have driven around it " with no further information.
I on the other hand have been forthcoming with information to individuals that have asked how to remove the dip. I have nothing to hide.
As far as my ET is concerned, I was getting a lot of spin between shifts. The track I was at is not nearly as good as Houston Raceway Park.
Futhermore, to fix the dip, you have to increase timing advance in the high and low octane tables. I'll post screenshots of my tables later tonight so you can see where the timing was added.
Its amazing how I try to post a fix on an ongoing issue and get called out about my ET. WTF?? When I say it worked...did you not notice the timing advance did not drop to 0* at launch??? Who cares if my ET wasn't faster.
" with no further information.I on the other hand have been forthcoming with information to individuals that have asked how to remove the dip. I have nothing to hide.
As far as my ET is concerned, I was getting a lot of spin between shifts. The track I was at is not nearly as good as Houston Raceway Park.
Futhermore, to fix the dip, you have to increase timing advance in the high and low octane tables. I'll post screenshots of my tables later tonight so you can see where the timing was added.
Its amazing how I try to post a fix on an ongoing issue and get called out about my ET. WTF?? When I say it worked...did you not notice the timing advance did not drop to 0* at launch??? Who cares if my ET wasn't faster.
drive around it!! you and many others are laughing, the ones that listened are going faster, i would advise you to due the same