I have another post for "what will it run", but I figured I would start another to keep it separate. I installed my 418 into my dad's 85 Shelby Charger and now installed the transbrake. The car is a full tube car with ladder bars and non adjustable shocks. I was launching at 3000 rpm on the 2 step and the car wanted to stand up every pass. It seems to be dead hooking. What do you guys to to calm down the launch? More tire pressure,different launch rpm?

Both 1 at a time so you know what one worked.If its radials it is totally different.

What trans? What is the gearing combo? Maybe you will need to lower the ladder bars one hole? Any video of the passes?

Trans is a 727 with standard gear set, 4.30 rear gear and 29.5 x 11.5W tire. I have a video from a cell phone that is not very good, but I will see if I can post it.

With the engine warmed up, with the car stopped, foot on brakes, put tranny in high gear, while watching the tach, floor it, and let off the gas right away. The highest rpm reading is your flash stall. Set your launch rpm 400 - 600 rpm under the flash stall. You'll shock the converter less than what you are now, and also the engine should be in it's sweet spot.

Link for video. Sorry its so bad, it was from a friend's cell phone

http://www.youtube.com/watch?v=7YiLqQKWCjo&list=HL1359653934&feature=mh_lolz

That isn't so bad..Here is my 3400# beater leaving at 3400 rpms..

That was the only video we got, some of the others were higher. The problem is the car is pretty low and the header collector on the drivers side is only about 2-3" from the ground and I would hate to smash it. With out the transbrake it will run almost as fast, but it does not pick up the front end at all.

Put a big block in it.......

Kinda hard to tell from that video but it looks like it pulled to the left on that pass. Looks like its lined up pretty nice so if it did pull to the left you may have to play with your ladder bar pre-load. Sounds great and its running some nice numbers.

Several things I have treid over the years to calm the car down on the starting line and limit the hieghts of the wheelies,stiffen up the front shocks or tie the front suspension down with a travel limiter,put the ladder bar in the lowest hole in the front, make the stall RPM as high as posiible so the motor CAN'T flash the converter at all, ie throttle on the floor on the trans brake when the first bulb lights up, WOT

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make the stall RPM as high as posiible so the motor CAN'T flash the converter at all, ie throttle on the floor on the trans brake when the first bulb lights up, WOT

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One thing to consider is just how much starting line ratio you have. At a certain point, the car can pull the front into a wheelstand no matter what you do, if it gets traction. Here are the numbers from my car, and why I fought wheel stands for so long.
106 inch wheel base = 8.833 ft.
800 ft/lbs torque x converter multiplication(2)=1600 x low gear (2.45)= 3920 ft lbs x rear gear (4.56) = 17875 ft lbs x .90 (driveline loss) = 16087 net ft lbs torque at the hit.
Rear tire radius is 33/2, or 16.5 inch. divide torque (16087) by tire radius, multiply by 12 inch, and you have the torque in ft lbs which acts against the whole car. Now divide that by the wheel base (8.833ft) and you know how much front end weight the car can DEAD LIFT, no spring help, etc.
Mine comes out to 1324 lbs. With a front weight of only 1480, it doesn't take much help at all to go on the bumper instantly. When you figure in the fact that the torque is actually working against a center of gravity about 20 inches off the ground, it reduces the required lifting torque even more.
You can move some weight forward, which to me is a better solution than tying the front down because you can shock the tires just enough to get the front in the air a bit, and after that the front/rear distribution does not mean a thing, the rear tires are carrying it all anyway. I made a change from 1480 on the front to 1600. That may seem like a lot, and it is. But the car is now controllable and very consistent. You could start with a big weight move, and see if more rpm will hook the tires. lighten the front back up as needed.

on the issue of weight distribution not mattering once the front wheels are in the air... what about the torque moment around the rear axle? a 35 lb batter over the rear axle has a torque moment of what..a foot? so it's a 35 ft/lb torque load....but if you put it way up front, that's 35 lbs times...10 feet? that's 350 ft lbs of "counter torque"

I'm still trying to learn as much about how to set up suspensions as I can, but it would seem to me that even if you DO have both front wheels in the air, and all the weight is on the rear, that your weight distribution can still have an effect on controlling wheel stands

also in that video...I agree, looks like he got squirley. does the car leave straight and the track had poor prep causing it to pull one way or the other? or does it do taht every time? it sounded like he had to let off the gas because of how out of shape it was getting.

I was hoping to make it out this Saturday, but it looks like I may have to go out of town for work. If I am in town I will be going.

I will have to try to see where the converter is flashing to and go from there. I think I only have a 3000 and 3400 rpm chip for the low side, but I will try the 3400 to see if it helps. I will probably have to look at the ladder bars as two of the passes did try to go left on the launch.

If the car was straight on the launch, you have too
much pre load on the right bar... that will drive it
to the left... increase in tire pressure will give
you a controlled slippage at the tire... I dont know
what pressure you have but try 1/2 pound increases
till you tune it in... that'll get you up on the tire
and should give you more MPH also... once you get it
close then its 1/8 psi for final tune.... from your
launch I would think its already in the lowest front
hole... but if it isnt lower that .... the pic in
my sig is great for pics but thats not how I normally
leave... more like this pic... in this pic the RPM
is lowered also

Just a thought here..and Mr P. can confirm this! When I first started using a brake,my car was pulling to the left,too. And the guy that did my chassis work is one of the best in the business! Turned out to be driver error. I was so used to footbraking the car and always launched with both hands on the wheel. My button is on the wheel and when I let it go,the car would come down and always go to the left. I changed my technique by resting my left arm on the door bar and holding the wheel in the 8:00 o'clock position..Bingo! Problem solved! I was jerking the wheel to the left! Car goes straight as an arrow!

I always rest my hand on my knee and hold the bottom of the wheel. Helps keep you from over driving the car.