302Travis

Hi guys, kinda new here and new to the 4.6L stangs. Anyways. I have a stock other than being lowered 1.5in 00' gt 5 spd. Took it to the track in high 80 degree weather and 70ish percent humidity at 2k ft elevation. Ran a best of 9.59@75 with my average 60' being mid 2.3 seconds. Full tank of gad and Tire pres. At 30psi, going back this friday and i know i could brak 9.50`s but im mostly needin to get the sixty foot down. Gonna run tires (nitto 555) at 26 psi and abt a half a tank of gas. I was dumping the clutch at 3000-3400rpm but thinking ill try slipping the clutch from 3500 or so. But any tips? I wanna improve sixty foot without any mods or going to a different tire. Just wanna improve on what im doing. I know i could provably hit a 9.30 or so at a lower elevation track

needmorespeed

I may be off base on this and someone will yell at me for sure, but when I need a good launch I dump the clutch at 2800, feather the throttle for just a sec while the tires spin and then once they hook, hammer down. I don't know if that will lower your 60 ft time, I haven't been to the drag strip in a while to clock it. Just food for thought.

302Travis

Mine just grips and bogs if i dump it that low. I may try that but more around 4k. These nittos are pretty sticky for a street tire imo. Another q is, where do you shift at? I tend to shift at 5800 but ive heard some people get better times shiftin at 6000?

needmorespeed

Its been awhile but I usually make sure to shift at about the same. My rev limiter is set to 6250 but I don't go that high. I shift at 6000, that way it just kisses the redline and drops back down. I run a tire with a 180 tread wear, just as a reference. I do get a slight bog once the tires hook but I think that is better than spinning the tires. Just my opinion, don't have any time slips or anything to back that theory up. I just know tires that aren't slipping have more grip than ones that are. In all fairness I don't do it all that often so someone may have better insight.

Stevo86

Why are you dumping the clutch in the first place? Unless you're running drag radials or slicks dumping the clutch is not going to help. That shock to the drive train will break the tires loose every time.

Try to roll out at a lower RPM and apply the throttle steadily to the floor. You may not think that a half throttle launch is faster than full throttle but you'll be surprised how much blowing the tires off slows you down.

302Travis

I think you have sorely misunderstood. I am not standin on it wide open and dumping the clutch. That would make for over 3 second sixty foots. I simply give it enough throttle to hit 3400 or so and dump it. Tires chirp and then the motor bogs. No roasting tires here. Just getting it to hop off the line a little then hammer down. Im gonna try clutching it hard and burnin some clutch to see what happens.

But point is, im not spinning, common sense tells you if you`re spinning you aint winning. But anyways. Im looking to launch hard but i wanna try not to burn clutch to do it. Thats why you dump it with a little bit of throttle.

302Travis

Yes to bog is better most of the time. And mine are 300 on treadwear.So your probably stick even better. I will try shifting at 6k then, because ive been kinda on the fence about that

reldla1996

Optimum shift point is dependent on a lot of factors, including cam and valve springs. Best way to find the optimum shift point is make several runs at different shift points, and see what your time slips show. The factory tach is also not accurate above 4000, and reads significantly high at 6000. On the launch, the higher the rpm the better as long as you don't spin tires. Slipping the clutch will likely help your times, but it sure is rough on the clutch...I don't do it. Again it's practice, raise your rpm's until you get tire spin, and then back off a little. Running quicker than that will require better conditions, more modifications, or better tires.

302Travis

My motor is completely stock. Even the mufflers are original. And if the tach reads high that may be why my trap speed dropped when i tried shifting at 5600 and 5400. Ive been skeptical on shifting at 6k because the tachs red mark is actually at 5800rpm. But ive revved it to 6k. But never hit thelimiter. So what is the stock rev limiter set at?

reldla1996

Stock rev limiter is 6250, and works very well, pretty smooth when you hit it. I think I hit the rev limiter on mine at about 7000 on the tach (it's been disabled for a long time now...). 6000 on the factory tach is not an issue, I used to take mine to 6500, but that was not with the factory cam. I'd rev it until you notice a loss in power, which will be before the 6250 rev limit with the factory cam. If you search, you'll find lots of discussion on the topic of the factory tach. That's why a lot of people go to aftermarket tachs.