I currently launch at 4000 rpms on the brake and it's smooth as can be. I tried a 4400 launch and I only tightened up the front shocks 2 clicks. Terrible wheel hop. Should I have tightened the rear shocks and left the front alone. I have a 4000 lb pickup with a BBC and a big tire. A new setup for me. I used to run a 10" tire.
Thanks

Floyd I would go back to 4000 and the other shock setting that worked for you.

I did and and it worked fine but I'm trying to get further up in the power band to go quicker. Maybe I need a year change. I'm running a,4:30 rear gear.

I would only change the rear gear if your finish line RPM was not where you want it.

I agree with you that you should have tightened up rear shocks first. Then if it is doing big wheelies work on front shocks.
Since you have went to a big tire are you sure tire pressure is right for that size and weight of truck?

I'm going through the lights about 6600. I think it would be better about 7000.
I'm running the same tire pressure, 10.5-11, and it's too heavy to do big wheelies. It just picks them up a few inches and carries them.

What is shift rpm?

Floyd,

I was at Beech Bend @ Bowling Green last weekend for opening day Bracket race. Track was OK while the sun was high, as it got lower, the track became treacherous. My car was running 1.01x 60 fts consistently but chattering. I softened the extension on the rear shocks, and it calmed it down. In the 4th round it skated off the line chattering. Lowered the tire pressure by 1/4 pound, and it went back to 1.01x. You might want to look at lowering your tire pressure a tad to see if the higher launch helps it to absorb better. And possibly soften the extension on the rears.

quote:

Originally posted by Bucky:
What is shift rpm?

Bucky, when I was running the D/G 10.60 index I was shifting at 6400 and lifting just before the lights.
Last weekend we got screwed because of the rain and didn't get any timesheets so I went into eliminations blind. Set the shift at 6800 but dumped water on the track and turned it sideways on the 7200 limiter. Got a clean run in rd 2, launched at 4000, shifted at 6800 and it still ran a 10.60. 60' was quicker, 330' was quicker, 660 was quicker but slowed on top. I think it's dyno time.

Floyd I had a motor yrs ago it did not matter if I shifted at 7K or 6K, it was the same. I am thinking maybe your combo is spot on with no improvements to be made. Are you running a turbo 400? What does your converter flash at?

quote:

Originally posted by Footloose:
Floyd I had a motor yrs ago it did not matter if I shifted at 7K or 6K, it was the same. I am thinking maybe your combo is spot on with no improvements to be made. Are you running a turbo 400? What does your converter flash at?

You might be right. I don't know what the converter flashes to or what it stalls at. It's an expensive A1 but my engine builder ordered it so I don't know. Just running index I was never concerned. Yes, it's a T400..