jazzman

I see a lot of guys with great times drag racing their Z06. What's the best technique to launch for ultimate jump off the line? For the street, to get a fast start, but not kill the clutch/drivetrain, what's a good way to get off the line? I put the car in competition mode and didn't want to drop the clutch or do anything that might overly wear the drivetrain, but I just bogged a bit off the line - I know I should experiment, but I figured I could save some wear and tear and ask the experts.

Also, when shifting between the gears, can I powershift (stay on the throttle), maybe with a slight liftoff, or better to lift off as normal? And if I don't use the clutch will I tear it apart if I do that too often?

Thanks a bunch - 500 miles on it, so got on it hard in a few gears a few times tonight, woo hoo! Still being fairly conservative until I both get a better feel for the car, and let it break in some more.

-- Gordie

J-Rod

You are going to have to bring the revs up a bit and slip the clutch a bit if you want killer ETs. It won't kill your clutch unless you are really hard on it (like me). Work on getting you launch RPMs to around 3000 and releasing the clutch as fast and as smooth as you can without spiining. This should give you about the best launch without sacraficing your clutch.

Tracy

Practice the art and technique of powershifting on another car first...like a Honda Civic or some other low-power stick car. All the better if it's somebody else's car, or a rental!!! ;) It's a bit brutal to be learning this on a car that could break itself while you come up the learning curve.

rfgoss1

Don't powershift this car. It doesn't like it. Besides, you can run low 12's without doing it and keep the car longer. I ran my car the second day I got it and it gave me a 12.3 at 117. this is a very fast and forgiving car for a stock ride. Unless you really need the extra two tenths you MIGHT get, dont powershift.
Just my not so humble opinion.
Rg :cheers:

z064ddle

Can you explain the reason why not to powershift this car and why it doesn't like it?

Thanks.

rfgoss1

In technical terms I can't. There are numerous guys that can and you can get opinions going both ways. I have been drag racing for years and when I bought my first C5 I asked a lot of fellow racers about powershifting. 9 out of 10 told me that they didn't think the gain was worth the damage to the car. I don't recommend it because clutches and transmissions for this car are so expensive. Its not like a normal setup with the bellhousing, clutch and tranny right where you can get to them. Labor to install a new clutch is high and a tranny is an expensive part. I am going to have mine rebuilt and beefed up very soon to take the power of the stroker I have coming next month. I guess that you could say that my opinion is purely anecdotal, so maybe some of the real techies on this board can chime in with real data.
Randy :cheers:

Xpander

Well I can tell you that I can speed shift as fast as anyone I know can powershift. It is all about becoming one with your car, and getting so good with your cars transmission that you won't gain any advantage in the 1/4 by powershifting. I had a 99 SS camaro with a 6-speed. Only mods and I mean only mods were 4:10s and pantyhose over the air box. The car weight was 3670lbs with me in it and It dynoed at 293 rwhp and 303 rwtq. With the car set up like this I speed shifted it to a 12.65 @ 112mph with a 1.93 short time, now with that low dyno and that much weight that take took some shifting skills. So point is learn to speed shift and not power shift your 50k car. It will save you I promise. The LS6 or any other engine for that matter doesn't like a missed shift when trying to power shift, you are probably showing the engine around 7k-8k rmps if you miss a shift while power shifting, not good!
One last thing, my personal advise is don't drag race your ZO6 more than a few times, maybe just to see what it will do. I had over 400 passes on my SS off the bottle alone, and it didn't have that same tight, sturdy quailty as other friends rides who didn't drag race their cars (drag racing pretty much destoys your car, but its fun). Last night at the local drags a guy in 02 ZO6 blew his clutch apart trying to drag race his car without the know how of shifting.
Best of luck! :cool:
Justin

jim482

Love the signature

J-Rod

Learn how to drive your car, and do what you feel comfortable with.

I disagree with some of the other folks about it ruining the car. Also, the motor cuts fuel at 6600. So, it won't go to 7 or 8K.

My shifts are fast and smooth. I have plenty of passes, and nothing is acting up. I am very happy with how smooth the 6 speed in the Camaro and the Vette is.

rbartick

I'm with J-Rod and Ric (Powershifter) on this. Ask this question to 5 different people and you will get 10 different answers. :boxing

Whatever makes YOUR car go faster down the track is the thing that you should be doing. Just enjoy yourself. One day at the track will provide more knowledge than spending 3 months reading this forum.

Xpander

J-Rod, your fuel cut off does occur at 6600 but that is really only helpful when you have the transmission engaged. If you are powershifting and miss a shift, you are flooring your gas pedal with out any resistance to the engine from the transmission. So YES you will show your engine easily 7-8k RPMS if you miss a shift while powershifting.
Also, J-Rod how many passes do you have on your ZO6?
Cheers!
Justin


[Modified by Xpander, 5:47 AM 8/17/2002]

johnboy00

Unless forced by the rest of the drivetrain (you hit a lower gear by mistake and release the clutch), you cannot rev past the rev limiter.

Xpander

Johnboy, were you at Fayetteville Motorsports park two weeks ago. If it is you, you left just before my friend in the white GSX eclipse announced over the intercom a race between you and him for $50. You should have still been there cause my friend ended up running a horrible 12.7 but backed it up the next pass with a 11.6.
Now let me get this straight, cause I could be wrong! You guys are saying that basically I can get in a ZO6 take transmission out of gear and put the pedal to the ground and at no time will the engine/computer combo allow itself to rev past 6600rpms? So as the rpms take all of .5 seconds to go from idle to 6600rmps then right at 6600rmps the engine will stop gaining rmps (ignoring the laws of Phyisics) drop back down to a safe rpm and then back at it again. Guys, people bend pushrods all the time with these pushrod V8s and it is because the fuel cut off isn't designed for the (not refering to anyone in particular) idiot who drops the hammer without being in gear. GM knows the rmps will only raise so fast when in gear so a fuel cut off while accelerating does work. Have you guys ever heard F body or C5 miss a shift and still in the gas, engine has an entirely different tone than just running her up to fuel cut off. Like I said earlier, I could be wrong but from what I have seen, read, done, I believe it is entirely possible to rev the engine to 7-8k by missing a shift and keeping the pedal floored.
I hope that the guy that started this tread doesn't ever have to find out whether I am right or not, best of luck to all and to all a good night!
Cheers!
Justin


[Modified by Xpander, 10:36 AM 8/17/2002]

Xpander

Hey I have an idea, is anyone willing to run Autotap on their Corvette while they sit in the drive way out of gear and lay the hammer down! We could settle it right now! :lol:
It was a joke guys, relax!
Justin

etekberg

:rolleyes: I think it's time to go back to Physics class.

Yes, if you floor the car in neutral it will just bounce off the rev limiter. This is also how two-step rev limiters work (sometimes called launch control). You can keep the car floored and the throttle plate wide open and it will stay at the programmed rpm +/- a few hundred rpm.

Classical law of physics states a drivetrain in motion tends to stay in motion unless acted upon by an outside force such as combustion or friction. That means all else being equal velocity tends to stay the same. That holds true for angular velocity as well. A motor at 6000 rpm wants to stay at 6000 rpm. The only way it is going to accelerate past 6000 rpm (assuming not in gear), is if the computer allows more fuel/air explosions to act upon the pistions.

If we applied your thinking to linear motion all you would need to do is launch your car off the line then shut off the motor and the car would continue accelerating, which is obviously incorrect.

I'll shutup now :blueangel:

JerryL

Nicely stated.

levettegrl

WOW! Impressive:) I have enjoyed reading this thread-don't know anything about launching my Z, but I sure love reading about the guys that do!!!

3Vettes@Home

Do you want me to teach you Leslie????

3Vettes@Home

Do you want me to teach you Leslie???? ;)

levettegrl

WHOAH !!!!

You bet Greg!!!!!