Steve Burger

iTrader: (33)

The car has a 4200 stall now. I will be going to a 5500 stall over the winter. I am blowing through the stall on the launch. That is the reason for the change.

Here is the issue. If I launch off the converter I get tire shake or wheel hop. This is with 15 PSI in a 28x10.5 ET drag, LCA in the middle hole and the QA1s at 4. I would expect this to get worse with a better converter.

My thoughts are to put the LCA in the bottom hole and stiffen up the shocks. Am I thinking right?

tektrans

iTrader: (23)

I think with the bigger stall the shake will get worse. Are you getting alot of squat in the rear? How heavy is the car? 15 psi huh? I almost wanna say it's like you're not making enough power to get those ET drags going right. How's the motor running?
I think stiffening the shocks will help, I wouldn't change the control arm setting just yet.
If it were me I'd start with stiffening the rear shocks a click or two and I would definately loosen the fronts up all the way, just to see if the weight transfer helps to get the shake out by putting more force down on the meats.

Steve Burger

iTrader: (33)

I agree the new stall will make the issue worse. The car is at 3250 with driver. Motor is running well. At the hit I am lifting the tires about 10", Blowing through the current converter, and then it gets lazy.

I don't get any squat. It launches very well. Weight transfer is great. I agree that stiffening up the rear is a good idea. I was thinking that dropping the LCA would hit the tire harder. But, one change at a time is a good thing.

BAIN

iTrader: (5)

I don't have a transbrake, but we run simular times with close to the same setup mine(28" ET Drags-stiff sidewall, 4.10 gear, 4800 stall, 3220 lbs, and Qa1's) I have the LCA's in the lowest hole because my car is lowerd and it hits the tires harder. For some reasion my car likes the rear shocks as high as I can get them without breaking traction (usually around 7-8) front's around 1-2, and 16-18 PSI hot in the slicks. Anything higher they spin and anything lower than 16 PSI hot they spin. Have you tried a higher PSI in the tires? Hope this helps.

Steve Burger

iTrader: (33)

Higher PSI is worth a shot. Thanks.

tektrans

iTrader: (23)

Sounds like it's bogging down after the launch. Goes back to what I said about the motor being able to turn those slicks right. How much power is your car making? Maybe you need a little more gear.
If you're launching well, I wouldn't adjust anything. Maybe less tire or a stiffer sidewall.

Steve Burger

iTrader: (33)

The car is making plenty of power. I ran these tires last year with about 50 RWHP less. The new engine on the dyno has a severe power sag where the converter should hit. This is one of the reasons we know the converter is all wrong for this combination. The gear is a 4.33 up from a 4.10. Adding gear has made the problem worse. It is going through the converter even faster.

tektrans

iTrader: (23)

So you think the converter is bad and going to the one with the bigger stall will get rid of the power sag? Maybe it is just the converter? Keep us posted on what ya come up with, I'm curious as to what the fix is gonna be.