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View Full Version : Best way to launch with high stall converter?



thunderjet302
08-25-2011, 03:08 PM
So as you know I have a 2800 rpm stall PI Stallion non-lock-up converter. I'm going to be headed to the track tomorrow night to have a little fun at T&T and I'm wondering what the best way to launch with the converter is, as I think I'm doing it wrong :hick:. Usually I just have one foot on the brake and one over the gas (engine at idle) and I just release the brake mat it when the third yellow comes on. This results in wheel spin and shitty 60' and 1/4 mile et's. Would it be a good idea to bring the rpms up to 2000-2500 and then release the brake and mat the gas? I thinking this *should* cut the 60' times down some. I'm thinking the subframes I added in the spring should help as well.

I'm also running street tires. I don't own any drag radials or slicks. I'm well aware that street radials = crappy 60' times.

86T-bird
08-25-2011, 08:52 PM
This has been my experience: If my car can hook, launching off idle will cause the converter to flash the highest, generating the best 60'. With street tires, no hook and lots of wheel spin.

Try loading the converter, it may lessen the flash and minimize the spin by not shocking the tires (and keeping the engine below it's power band). Another option is to roll into the throttle. Both will probably slow your reaction times, but you can adjust where the car in the staging lights to accommodate for that (ie. roll further in. You can stage "deep" which means the first light goes out)

Generating 2.0 plus 60' times kind of takes the fun out of trips to the strip..., but you learn something every time you go. You can work at tuning tricks and pick up MPH. Once you get tires and probably some suspension bits, then the fun begins!

ZondaC12
08-25-2011, 08:52 PM
There's no cut-and-dry "step by step" way to do that. Launching a car is like learning to drive stick perfectly from the perspective of someone that has no idea what that 3rd pedal is there for. You have to learn to feel it out. Hopefully T&T there allows you however many runs you can get in during the time they're open? Just gotta keep at it and try to ease into the gas as hard as you can, stupid as that sounds. :hick: If you had sticky tires and some drag suspension components, yeah you'd flash stall it or just hold it right at stall to the point that you can just barely hold it back with the brakes then just nail it and get the most out of that converter. Once my friend's dad welds up my subframes already (a year and three months now it's been apart haha) I can't wait to see what the red car does with *roughly* the same power range and exactly the same drivetrain you have. It would spin like a whore forever as it was....

thunderjet302
08-26-2011, 11:18 AM
This has been my experience: If my car can hook, launching off idle will cause the converter to flash the highest, generating the best 60'. With street tires, no hook and lots of wheel spin.

Try loading the converter, it may lessen the flash and minimize the spin by not shocking the tires (and keeping the engine below it's power band). Another option is to roll into the throttle. Both will probably slow your reaction times, but you can adjust where the car in the staging lights to accommodate for that (ie. roll further in. You can stage "deep" which means the first light goes out)

Generating 2.0 plus 60' times kind of takes the fun out of trips to the strip..., but you learn something every time you go. You can work at tuning tricks and pick up MPH. Once you get tires and probably some suspension bits, then the fun begins!

Hooking is not happening nailing it from a launch. I've tried to roll into the throttle but I get excited and just nail it like a moron:hick:. Staging deep has cut my '60 foot times a bit but the best I've managed before my subframes was a 2.1 on street tires loading the converter a bit (1400 rpm). Maybe I can get that magical 2.0 with the subframes. I hope they help a bit.


There's no cut-and-dry "step by step" way to do that. Launching a car is like learning to drive stick perfectly from the perspective of someone that has no idea what that 3rd pedal is there for. You have to learn to feel it out. Hopefully T&T there allows you however many runs you can get in during the time they're open? Just gotta keep at it and try to ease into the gas as hard as you can, stupid as that sounds. :hick: If you had sticky tires and some drag suspension components, yeah you'd flash stall it or just hold it right at stall to the point that you can just barely hold it back with the brakes then just nail it and get the most out of that converter. Once my friend's dad welds up my subframes already (a year and three months now it's been apart haha) I can't wait to see what the red car does with *roughly* the same power range and exactly the same drivetrain you have. It would spin like a whore forever as it was....

Yeah we have pretty much the same set up (my cam is slightly more agressive that a stock HO cam, you have a ported to hell HO intake, and our converters stall with in 200 rpm of each other, both being non lock-ups) and mine spins like a whore too:hick:. Based on some calculators from e.t and mph the car is making some where between 234-240 hp at the wheels and 260-270 at the flywheel. Nothing that's going to set the world on fire but I'd like to run a 14.3-14.4 on street tires.

I'm still going to get my ass handed to me by all the 12 second cars there.

ZondaC12
08-26-2011, 03:35 PM
Dude if you get that thing to....semi-hook :hick: you should be better than that. It is a pig, but I know we're similar in weight and once you actually get that one right launch it'll feel that much faster. One night on a road in the middle of nowhere I somehow grabbed, and I didn't roll into it real light either, I think they were hot from cruising around and the road was gnarly, but my Gtech said a 0-60 of 6 sec flat and usually 6.4 was the best I could do. All I know is it felt like a launch too.

In the end....you gotta just make sure you enjoy the thing. If you do...that's all that matters. If you wanna be a contender...sell everything you own so you can dump another 500 bucks in a black hole every week so you can go scatter it all over the track again the next week. :rollin:

thunderjet302
08-26-2011, 11:09 PM
Lets see tonight's results:

First my best run tonight. Just flooring it off idle, 10-15 feet of spin:

60': 2.21
330: 6.16
1/8: 9.47@74.01
1000: 12.33
1/4: 14.74@ 93.34

Best run ever (to date not tonight)

60': 2.20
330: 6.11
1/8: 9.39@74.42
1000: 12.24
1/4: 14.65@ 93.29

Now lets see what happened when I brought the converter up to stall speed. I spent 25 feet spinning and drifting sideways:hick:

60': 2.72
330': 6.87
1/8: 10.22@73.07
1000: 13.12
1/4: 15.55@ 92.68

So what have I learned? Well for one I think I need new valve springs. Currently the heads are running 93 Cobra replacement springs, which are technically not what Comp recommends with the cam. I'm thinking the proper springs may gain me a mph or two. Second I need to build the 8.8 I have in the garage so I can run stickier tires and not worry about grenading the rear end. Third if I really want to go fast I need a better set of heads;).

I did win two races tonight. I smoked a 78 440 powered Chrysler New Yorker by 3 seconds and a mid 90s Civic by 2 seconds. The closest race I had was a 96 LT1 powered Firebird. We both ran 14.7s. Most of the street cars tonight seemed to be about .1-.2 seconds slower than usual, according to their owners.

I went on the scale tonight. With me (152 lbs) a 3/4 tank of gas my fatty weighs 3703 lbs :banana:.

86T-bird
08-27-2011, 10:04 PM
Sounds like you had fun.

In my opinion, your trap speed seems low for the set up. I'd expect 99-101 MPH.

Looking at the valve spring may be a good place to start. Based on a power peak of 5,400-5,500, it should pull to 5,800-5,900 as a shift point. If it's laying down before this, springs are likely weak.

t.birdsc
08-27-2011, 11:46 PM
x2 on the valve springs. All the Gt40 spec springs are weak. Comp makes a #26140 beehive but that has a bottom od of 1.445". What is stock diameter for the p's? The y's have 1.50" diameter but that 26140 spring may too much @ 377# open. The 26986 is a beehive that is 1.415" on the bottom od and 284# open.
If everyone is running slow and you are running the same you should improve when the weather is cooler. You should have more seat time then with the new setup. Next time roll into the staging lights and leave earlier. If you see the green light when you leave....leave sooner. If you leave on the 3rd yellow, leave on the 2nd and like try to red light. Every .1 you make in the 60' will help you .2 on the top and your mph will go up watch.

Mike