need help with 60' times

[pro318]

i'm in need of some help with getting my car to 60 foot constantly on the stop. right now i leave at wide open throttle 6000 rpm(play back after every pass and it's at 6000) 6.5 psi in rear on hoosier. tires have about 30 passes use to run goodyears at the same. one pass it'll go 1.51 then the next run it'll go 1.60, then go 1.55. i've checked for coil bind, sticky calipers, line lock is releasing.

[Dave Steltz]

Can you give us a little more info...
Whats your first number at
Whats your RPM on the stop
Whats your time on the stop
Approx Hp, and whats it run wide open

All could be helpfull in making a guess...plus do you have a data recorder or a playback tach ?

[pro318]

first number is .200. second number is around 2.00 dependes on the weather. makes 650 hp at 6700 shift on rpm at 7000. weighes 2400 with me. goes 9o's at 1.26 in 60.

[pro318]

forgot 4300 on the stop and have a playback tach

[Lou SG2340]

Are 60' times constant with the stop off? If yes, then you need to see if it is maintaing a constant RPM while on the stop.
Since you are shifting on RPM it will increase RPM while on the Stop. It needs to increase the same amount all the time.
Shifting by time might solve the problem.

[Dave Steltz]

I would look at two things..

First I'm assuming that you are running 10.90 (with 2 secs in the stop)..

I would try shifting on time, like at .3, and see if that makes it any better...if you play back the tach, are you gaining alot of RPM before the stop comes off ? If so this could make you're 60's inconsistant...if you cant shift on time try lowering your stop RPM to 3900-4000, this can help with the RPM gain...

Secondly, you may be spinnning at the hit, are your reaction times varying with the 60 ? If you are spinning lowering your starting line RPM , along with changing your first number to .05 can help....

[Charlie Yannetti]

I think Dave may have hit on it with spinning on the hit.. 6.5 lbs at 2400 lbs sounds at bit low to me.. you might want to try bumping up to 7 or 7.5 before you start chasing ghosts.. if it gets better at 7, then try 7.5..

[TinSoldier 3215]

He would want to lower his air? If he is spinning at 6.5 and you put more air he should spin more. We run 4.7 at day time and if track is good we run 5.0.

[TinSoldier 3215]

This is a door car. I'm sorry we run a dragster. I was reading his post and he could be leaving way to high on rpm's try lowering to 4,000 to 5,000.

[GaryGoFast]

I also think you should,

1. Leave at a lower rpm, at 6000, you should be holding a lot in the delay box, leaving at 4000-5000rpm would allow the hit to be more less agressive tightening up your 60ft ets and would just adjust the delay less. Lou is also right about the car being consistent out the door, if not theres your starting pt.and you should get that sorted before using a stop.

2. Does you pedal have a definitive stop on the firewall and does the firewall flex when you pound the pedal.

3. If you shift on time car will also get more consistent as Dave said but having the motor to pull you thru in 2nd gear is important as the convertor gets stressed coming off stop at say 4200 rpm .

4. I run 9 psi in my 16x33 tiresfor s/st, leave at 5200 1st # .05, shifting at .75 at 4100,4200 stop rpm weather dictating.