60ft question for all you drag racing gurus.
I am running M/T DR's on 16" CLK wheels, which instantly resulted in a drop from 2.0 to 1.83x in 60ft times. The ET went down from 12.6 to 12.3 and as I learned to use the DR's I started pulling consistent 12.2 @ 114.mph However, despite launching from a dead hook I cannot break out of the 1.83x times. Also, last week I installed an 82mm TB and had Mike from EC flash a box tune on the car, I took the car to the track almost immediately, and my times went down to a consistent 12.04- 12.05 @ 116mph. However, the 60ft times still stayed in the 1.83 range. The best time to date was 1.816.
Just to give some background on the car, it is running a stock pulley, has a resonator, secondary cat delete and an 82mm kit with a box tune. The DR's are set at around 18psi. IAT's are in check with a larger H/E and a fresh pump(around 138 by the end of the track). No DTC's, tried sneaky resets and all the adaptations. The S/C belt has around 5-6k on it and the car peaks at 10psi and seems to hold 8-9 psi under heavy load. There are no boost or vacuum leaks.
As a side note, the previous owner did have glycol problems with the transmission and had it rebuilt, however I can not vouch for the torque converter. At this moment I am starting to suspect the TC, since it did give me the usual glycol shudder and drone until I flushed the entire system. It's been driving well since then but it does seem the lock up is acting up in the TC causing the car to upshift too soon and drag the TC on decel. All the adaptations are well within spec, solenoids are all new, conductor plate is fresh as well.
I know it got a little long winded,but maybe someone can point me in the right direction. So to all you drag racing aces, do the 1.8x times make sense on DR's with a dead hook, or should I be looking at a low end power delivery problem?
Sorry, I missed the 82 mm TB.
Last edited by cal1; Aug 28, 2012 at 07:14 PM.




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It does not feel like the car bogs, but I do have a feeling that I am down on torque. In the 1/8th I am at 91mph for the 12.0x runs and usually right around 89-90mph for the 12.1x
My rear main seal has been leaking for a while, so I might just throw in another torque converter while I'm in there since I've been having some odd behavior from the transmission since day 1.
Thanks for all the responses, I'll keep digging
It does not feel like the car bogs, but I do have a feeling that I am down on torque. In the 1/8th I am at 91mph for the 12.0x runs and usually right around 89-90mph for the 12.1x
My rear main seal has been leaking for a while, so I might just throw in another torque converter while I'm in there since I've been having some odd behavior from the transmission since day 1.
Thanks for all the responses, I'll keep digging
* run the car in dyno mode, tranny in s mode, and suspension in c setting, not raised.
* clk steelies with hoosier drags at 13-14lbs typically but varies depending on how the track hooks.
*burnout for a good 5 seconds letting slowly off the brake so that you smoke the tires up to the line.
*power brake and launch off idle, then put your foot through the floor board.
Result: 1.5x 60's consistently.....
You will either hook or spin, if I spin, abort the run and try again.
Have you dynoed your car? Take it to a dyno and do a run from low rpms to redline. You may find your answer.
I have been pretty religious with this launch technique, so I might need to experiment with the ESP/Dyno mode, as well as powerbraking a little to as previously suggested.
Chawkins2001 could you elaborate on the power braking/leaving at idle part? Do you power brake to preload the TC and get some flex out of the driveline to like 1100rpm and then just let go of the brake/go WOT simultaneously, or are you completely at idle when the light turns green and just power brake for a second to get the rear end to dig in a little.
Thanks again for all the suggestions!!
Last edited by BBBSS; Aug 29, 2012 at 08:52 PM.
To the OP: after you stage press the brake then give it a little gas to raise the rear of the car a little more and take some slop out of the driveline. ESP off or even in dyno mode. Then try to floor it and see of it hooks and go from there.
82mm TB, EC tune, stock pulley, MT drag radials, resonator/secondary cat delete, Frozen Boost H/E.
Last edited by Lelix; Oct 13, 2012 at 10:59 PM.





