unicron,

I thought the reaction time doesn't affect the overall ET of a drag race. Doesn't it still record the same ET no matter what your reaction time is?

Everyone,
Is it best to shift at redline @ every gear?

 

While we are talking about this could someone explain correct shifting technique. Take your foot completely off the gas before engaging the clutch? Stuff like that. I am a much better shifter under pressure. Driving it around slow it seems I give it a little gas before clutch comes back out and it kinda barks......nothing significant but still it bothers me. I am always feeling every shift and sometimes they just dont click right.
Z34 pulls up to me the other day, I bark second and come around a rotary sideways nailing third out of the hole......cya. Damn it was perfect. Goto the store I am like where the hell did I learn to shift?
Any info would be nice.......probaly I will attend a racing school or something but hearing it now I could pinpoint my mistake.

Peace

Vain Glutton

 

[QUOTE]Originally posted by mistersleepy
[B]unicron,

 

Sev's analysis is correct. Just removing the spare, jack and book bag will net you approximately 0.1 seconds and 1 mph. Running 1-2 gallons of fuel will help proportionately less.

Additionally, every tenth you save in 60 ft times is worth at least a tenth at the end of the strip, usually it's closer to two tenths. Get your 60 ft time into the 2.0 range and you'll be running 14.2 or better even without improving your shifting.

Your car is certainly broken in and you were running fresh oil, so that's good. High humidity doesn't help, but temps were nice. If you can find the elevation that will shed some light too. Anything under 500 ft is no big deal. 500 ft to 1000 ft can cost you a tenth or two. Above that you start to lose time. Running at Firebird Raceway in Phoenix (about 1200 ft) my other car runs 0.2-0.3 seconds slower than it does at 300 ft in Carlsbad, CA, and Firebird has a better track surface. Run in Albequerque, NM (3,300 ft) and you'll lose 0.7-0.9 seconds. Run in Denver (5,200 ft) and you'll lose well over a second (at least, cars running normally aspirated with similar ETs to ours will).

When you get right down to it though, improve your shifting time. A good shift should take no more than 0.2-0.3 seconds, max and a great driver can be even quicker. The acceleration of a car when shifted properly is almost seamless. Lose a tenth on each shift and you can see where you lose a few tenths and a mph or two. I pulled some timeslips out of my files to find some with similar 60 fts, ETs, mph, etc. From comparison, it looks like you probably did pretty well on the 1-2 shift. Provided you don't grind that one, its hard to mess up and you aren't going to miss the rpm point too much. After that though, I'm betting you were a little slow on the 2-3 shift. Its o.k., that's always a tough one because you're moving in two axes instead of one. The 3-4 shift is also suspect, but because of the low trap speed, I'm betting you rushed that one and shifted before the limiter.

In terms of where to shift, according to my dyno charts shift at redline until the 4-5 shift where you want to shift 100 rpm early and about the same for the 5-6 shift. Of course, that's nearly impossible with our tach, so just shift on the 2nd blink :-). If you have a Mugen header, you'll actually want to shift the 3-4 about 200 rpm early, and the 4-5 and 5-6 about 400 rpm early.

UL

 

I always come out of the gas by 80% before going in on the clutch. I tried driving it around tonight, pegging the redline, with only coming out on the gas 20% before shifts. It seemed to work better - the car felt faster.

 

[QUOTE]Originally posted by TunnelNightCLB
[B]While we are talking about this could someone explain correct shifting technique.