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Traction
As a high school auto shop project we built a 79 Luv drag truck. It has a 383 smbk for power. 23 degree T.F. heads, .560 soild lifter cam at 265 duration at .50 - 3500 to 65000 rpm range, 700cfm dbl Holley, 10.5 comp. ratio and runs through a set of 4.10 gears. 28X10.5 M/T at 8psi.
At launch the front wheels lift 6". 60' times 1.48 with 7.0 in the 1/8.
Stock leaf springs with the overloads fliped over on home made SSM lift bars. New drag shocks too.
After launch it starts to gallop up and down but with out wheel hop.
Sounds and looks strange.
Last year with a different cam (it Had a high RPM cam - 4500 to 8000)
you could count the slick's stripe 3 turns before it blurred into acceleration. Now it spins immediately off the line. How do we kill the low end power until it gets out of the hole?
Mr.T

Retard the timing, if this is allowed in your type of racing, (some classes don't allow it) you can get an adjustable timing retard that will pull it out at launch and add it back gradually. If timing controllers are not allowed, just retard it and leave it...

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mytmouz,
We usually run 34 degrees so we can run pump gas. How much retard would you start off with?
We have a light advance spring and full advance comes in at 2300 is this still ok?
Mr.T

The more you retard it, the more sluggish it will be. trial and error methor is probably best. Drop it down to 30 and start from there. The advance curve doesn't do much at the track since you are mostly at WOT. A friend of mine is trying to run a 615 BBC with a stock suspension on A S10. At Atlanta this past weekend for the Pinks! All out he ran his timing @ 12 to get down the track without blazing the tires...

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Try firming the rebound a little to take the bounce out of it .

sounds like spring wrap to me? i have a 76 with a 406, 500 gear ,stock supension with 13 year old stock shocks and was cutting 1.47/1.48 60's,then i put traction bars on and i got bad wheel hop, i took them off and it was fine again but my tire is a 29.5/10.5/15 MT, i just recently put hoosiers 29/9.0/15 on and everything went to hell...1.50 60's and went from 6.64 to 7.00 in the 1/8th. what is the pinion angle on the rear end, could it be rotating to much and unloading, i have 5 degrees down.

Fellas,
Thanks for your input. Went to the drags on the 24thof May.
When the engine was installed in 93 I had he students crank up the torsion bars to level the truck. This week end Alex suggested we lower it so the fender lip was 1" above the tire. This made all the difference as the launches smooth rightout and it started to hook. I checked the pinon snubber clearance which we set at 1" and found it now to be resting right on the housing! Did we kill the leaf springs?
The new cam and engine combination really leaned out the engine.
We went from 78 jets to 84's and the mph went up every time. On the last run the plugs just started to show some color. Changed the shooters and it got better (32 and 35) but it still isn't
spot on. 35 and 37 was to large.
Mr.T