View Full Version : Best way to launch with auto?


critter
05-11-2005, 10:40 PM
I'm wondering what the state of the art is today. Back in the day, my B&M hydro with 3500 stall launched best nailing it from idle until I got it dyno tuned and lost it's throttle response. After that it launched best at 2800 or so, but not as good as before.

What is good today, say with a stock converter?
With a 3500 RPM stall converter?
With a 5500 RPM stall converter?

Villain281H
05-12-2005, 07:24 AM
I launch with my stock convertor between 900-1000. The Nova has a 3400 stall 10" convertor, and I launch between 1800-2000. You want to have some flash on the stall, but not have it so high it just pushes through the beams.

Derek

critter
05-12-2005, 11:11 PM
I launch with my stock convertor between 900-1000. The Nova has a 3400 stall 10" convertor, and I launch between 1800-2000. You want to have some flash on the stall, but not have it so high it just pushes through the beams.

Derek Thanks for the reply. Sounds like you go a little more than half the stall speed with the loose converter?

Villain281H
05-13-2005, 04:21 PM
when footbraking it, that's about right. When/if transbraking it, go as close to the stall rpm if your suspension can handle it.

Derek

critter
05-14-2005, 12:12 AM
when footbraking it, that's about right. When/if transbraking it, go as close to the stall rpm if your suspension can handle it.

Derek
Thanks for the reply! This thread is getting looks, so somebody besides me must care ;)

Any idea way you want to go higher with a trans brake? Is it because the locked transmission can hold it but the brakes won't? I guess that makes sense ... at some point sticky 10" slicks should be able to push skinny front tires right on through the lights.

Do you still get the flash effect running the engine that near stall? For that matter, is the flash effect useful for more than lifting the front wheels for a few feet?

TWS
05-14-2005, 09:49 AM
Thanks for the reply! This thread is getting looks, so somebody besides me must care ;)

Any idea way you want to go higher with a trans brake? Is it because the locked transmission can hold it but the brakes won't? I guess that makes sense ... at some point sticky 10" slicks should be able to push skinny front tires right on through the lights.

Do you still get the flash effect running the engine that near stall? For that matter, is the flash effect useful for more than lifting the front wheels for a few feet?


Yes, the use of a transbrake allows you to bring the RPM up much higher than you would foot-braking it. You cannot bring a motor up to the converter's stall speed while holding it still at the tree just using the brakes. Well before the stall speed, the car will start to buck and then push your front tires through the beam and trip the lights.

NufNuffZ28
05-14-2005, 10:58 AM
I have best luck on 3200-3500 stalls launching from about 1100.

That lets teh converter do its job of flashing and getting you out of the hole!!


Best 60' is 1.50 in the Iroc with 3.73 gears and stock 10 bolt. Converter is a Coan 10'' 3200


Chris

critter
05-15-2005, 03:56 PM
I have best luck on 3200-3500 stalls launching from about 1100.

That lets teh converter do its job of flashing and getting you out of the hole!!

That is pretty close to idle, just like I did with my B&M hydro back in the day
.

Best 60' is 1.50 in the Iroc with 3.73 gears and stock 10 bolt. Converter is a Coan 10'' 3200

Chris That is a good short time for 3.73 gears. I guess flashing must work.

00Z28 Camaro
05-15-2005, 05:00 PM
I have best luck on 3200-3500 stalls launching from about 1100.

That lets teh converter do its job of flashing and getting you out of the hole!!


Best 60' is 1.50 in the Iroc with 3.73 gears and stock 10 bolt. Converter is a Coan 10'' 3200


Chris


1.5 60' mother of god :hail:

Villain281H
05-15-2005, 10:30 PM
I've tried mine between 1600 and 2000 rpm and the et's don't vary much, but the reaction time does, and since I bracket race the car, I'm concerned with that. the most I've ever gotten it to hold on the footbrake is 2500 rpm, but it was leaning HARD!

Derek

NufNuffZ28
05-16-2005, 04:46 PM
Not a great launch....I had some spin, but here is a video with a 1.59.


http://www.hpjvids.com/humor/nufnuff.wmv

Chris

white_ta
05-18-2005, 01:06 PM
Not a great launch....I had some spin, but here is a video with a 1.59.


http://www.hpjvids.com/humor/nufnuff.wmv

Chris

Nice.

rebersole2
05-18-2005, 08:43 PM
I use a TCI Super Street Fighter (3500- 3800 stall) on my footbrake combo. I launch about 1800- 2000 rpm. Just enough to clear his throat and it helps avoid any bog situation. My older car was a quite bit quicker and had a 5500 stall, but it launched and responded much better when I nailed it off idle. I too, agree with Villian.

Kirby
05-19-2005, 03:01 PM
I'm about to get a 3800 stall with a high STR. Hopefully with the high STR I won't have any bogging problems, just traction problems. ;) I need a big stall because my car has 2.73s and is running a 13.7 1/4. I know its slow but I'm still working on it. How high do you think I could foot stall with a 3800 lock up converter?

y2k_ta
05-20-2005, 07:13 PM
I launch my stock converter at 1,000 RPM. I used to just launch at idle when I had 2.73's, but since I switched to 3.73's that changed. If I don't launch it at 1,000 RPM, the car falls flat on it's face.