LETS DISCUSS DRAG RACING A ZL1

[jessrayo]

Originally Posted by GriffJ

I was about the make this same thread. I had some experience at the track(not much and 10+ years ago) from my LS1 cars. I ran my stock 6 speed 2002 Z28 and ended up with a 13.0@108. This was with 315RWHP in an almost no option car. How much harder is it to run the ZL1? I know my Zl1 has about 1k pounds on my 02 but it also has about 185RWHP.

That 13 second run just about torched the clutch in the 2002 as well. Is the clutch as weak in the Zl1 when you are abusing it a little?

The stock clutch does surprisingly well with stock horsepower, some have gone a full season with stock power on stock clutch and no problems. But when you raise you dyno numbers the clutch goes south really fast.

Originally Posted by white ZL1

I'll disagree with this only because the term "redline" means different things in different cars or with different parts combos.

Is "redline" where the red line is actually at on the factory tach?
Is it the rev limiter that you or your tuner have set in the ECM?
Or is it the max rpm that the engine and valvetrain can hold together at?

Good general rule...shift the car where the area under the curve is greatest. Typically this will be a few hundred rpm after peak power.

For me it means the limiter. Hopefully if you have a tuner he didn't raise the limiter beyond the mechanical limitations of your valvetrain.

I don't care where the limiter is set at, even if the dyno curve has passed it's peak by a little the car will produce faster times if you run the low gears right to the limiter because the car will accelerate faster in first after the peak than it does in second in front of the peak. The further you run out the lower gear the higher the car is on the power curve when you finally do shift it. Andy has data logged my car and it is clear that the very fastest times are achieved when the clutch is engaged right before the limiter.

I know exactly what you are saying and I used to want to shift closer to 6000 but Andy showed me the logs and told me I had to let it run and he was right.....as usual...lol.

[Cooks ZL1]

Bigtime what is your mods that make your car over 700rwhp?

[white ZL1]

Originally Posted by jessrayo

I don't care where the limiter is set at, even if the dyno curve has passed it's peak by a little the car will produce faster times if you run the low gears right to the limiter because the car will accelerate faster in first after the peak than it does in second in front of the peak.

Power under the curve then?
Maybe with the M6 the rpm drop on the 1 to 2 and 2 to 3 shifts drop you a little too much? And there's no shift extension like there can be with a torque converter.
My car made peak power at 6000rpm, but the LS9 cam basically carries it to 6500rpm. The power doesn't drop, but torque does by about 60lb/ft. And it's made it's fastest passes shifting right around 6400/6500.

[jessrayo]

Originally Posted by white ZL1

Power under the curve then?
Maybe with the M6 the rpm drop on the 1 to 2 and 2 to 3 shifts drop you a little too much? And there's no shift extension like there can be with a torque converter.
My car made peak power at 6000rpm, but the LS9 cam basically carries it to 6500rpm. The power doesn't drop, but torque does by about 60lb/ft. And it's made it's fastest passes shifting right around 6400/6500.

I think the actual mathematical explanation would be to take the engine torque/power and multiply by the overall gear ratio and then if you could subtract drive train loss. This should show that net power in the lower gear is greater than the power at the lower rpm and lower torque multication of the higher gear. Overall rpm drop varies with every gear change but the shifts always put the engine at an rpm well in front of the peak and it loses some of the multiplication effect of the gear itself. I just read what I wrote and it sounds confusing to me...lol.

I just know I run faster if I shift closer to the limiter.

[Ledbetterjw]

If drag racing is your goal, it's stupid to start with a zl1 as your platform.

[GriffJ]

Originally Posted by Ledbetterjw

If drag racing is your goal, it's stupid to start with a zl1 as your platform.

It is something I might do once a year. I hear that have some stuff over at COTA for road racing. I'd be interested in that every once in a while as well.

[Emvici]

Well like anything (mrvenicess) you learn the program and its auto repeat. However most people aren't perceptive enough too consistently analyze all the factors necessary to obtain a 1.50.

[white ZL1]

Originally Posted by Ledbetterjw

If drag racing is your goal, it's stupid to start with a zl1 as your platform.

Stupid huh?
Why's that?

[Emvici]

some people overlook that fact that there are different categories for cars within the sport of drag racing.

[Bigtime53]

Originally Posted by Ledbetterjw

If drag racing is your goal, it's stupid to start with a zl1 as your platform.

WHY? Please explain your reason

[Bigtime53]

Originally Posted by Cooks ZL1

Bigtime what is your mods that make your car over 700rwhp?

ANDY at ADM built the motor.It has the ported supercharger,ADM stage 2 cam for the automatic,injector dynamics 1000cc injectors,stainless works 2" headers,stage 2 ported polished heads,ati dampner,9:55 ring and he tuned it.It makes 711.59rwhp and 619.33 torque.Kinda wish it would have been around 750-ish but it is ok like it is.Andy does very good work and he is the only one that I will let work on the car.

[Bigtime53]

Originally Posted by jessrayo

I think the actual mathematical explanation would be to take the engine torque/power and multiply by the overall gear ratio and then if you could subtract drive train loss. This should show that net power in the lower gear is greater than the power at the lower rpm and lower torque multication of the higher gear. Overall rpm drop varies with every gear change but the shifts always put the engine at an rpm well in front of the peak and it loses some of the multiplication effect of the gear itself. I just read what I wrote and it sounds confusing to me...lol.

I just know I run faster if I shift closer to the limiter.

Damn Jess I only have a high school education!!! You might want to try to explain that in laymans terms!! {I don't think I spelled that right!}

[jessrayo]

Originally Posted by Ledbetterjw

If drag racing is your goal, it's stupid to start with a zl1 as your platform.

I don't think GM has ever made a better starting platform for drag racing than the ZL1. It has some frivolous dead weight like heated seats and huds but you can remove them a lot easier than replacing and re-enforcing the entire driveline. The ZL1 drivetrain can handle 1000hp in either auto or manual. Think about that for a second. It makes a good drag car.

Originally Posted by Bigtime53

Damn Jess I only have a high school education!!! You might want to try to explain that in laymans terms!! {I don't think I spelled that right!}

If your first gear ratio is 3 and your second gear is 2. Then in first the engine will spin 3 revolutions to one turn of the drive shaft in first and only 2 in second gear. The first gear will allow you to burn up more gas and gas makes power and acceleration so if you keep it in first as long as possible you will be faster. The same thing happens with each following gear change. Even though the engine may have passed its peak on the rpm graph, the transmission is still multiplying power for a bigger advantage in lower gears.

[mlee]

Originally Posted by Bigtime53

WHY? Please explain your reason

X2 and what other Camaro street legal platform would you start with?