Traction

BCompy · #1 (**permalink**) 07-17-2006, 06:49 AM

Hey Guys, Just got back from a boys weekend of Drag racing ,shooting guns wildly but safely ,drinking to much after guns were secured, and eating terrific but unhealthy food . Spent so much time laughing my face hurts.
I was there to uphold the honor of the Classic Roadster (only one from the club that could go) and believe I did. Only loss suffered was to a new Z06. I ran a 12.01 to his 12.03 ,he caught me sleeping at the lights. Dam that hurt. I think he should have set me out a car lenght for every ten thousand his car cost more than mine. I thought the car performed very well for a crate 351 on giggle juice and 119 thru the traps.

Anyway the only weak stop that was rearing it's ugly head was the rear end. I was running BFG drag radials and they were biting great. So great the rear was doing a little dance under launch about the 8th pass. I am pretty sure the springs wanted to come off the perches. This car has the stock 79 style unboxed trailing arms, blue coil springs and gas shocks. It is almost 100 percent street driven so I don't want to get crazy with modifications. Does anyone have a suggestion how to secure this diff. I believe someone posted he was running coilovers and left his coilsprings in place. Would that help ? This two hundred mile trip to the nearest drag strip was an unqualified success so I guess we are going again. The only thing missing I am told was naked girls on trampolines.

JAM1775 · #2 (**permalink**) 07-17-2006, 12:49 PM

Bill.....could this be wheel hop ?? If so there is a fix for that with your 4 link suspension. I'm not sure I saw your wheels hopping severely but you could feel it through the chassis, steering wheel etc. It's caused by traction and the rear actually winding up then snapping back. The car shakes in all directions but feels like front& back shakes. If this is what you feel, the fix is in the upper/lower control arm angles, checking the pinion angle, setting the Instant Center and Anti-Squat. Most likey the latter two are where you'd be your concerned. In any event it sounds like a job for a shop with race chassis experience. There are 3 places on LI you can bring the car to....one is Pittbull on Edison Ave. The other is Delmonte Motorsports off Vets Highwy, Bohemia area. The third is down the block from MM. They can look at your rear end geometry and predict how your rear will react under traction. The diagnostics alone is well worth it.
Okay......I'll go back !! Woo Hoo !

BCompy · #3 (**permalink**) 07-17-2006, 03:15 PM

No Jim the launches were flawless. It left like a fighter off the deck. When I was heating the tires and released after I came to a stop the rear was catching up with the chassis. It was actually clunking into place after I stopped to roll back to the line. I really thought I was going to pull the coils right off the perches.

It left grease smooth ,no hop at all.

I spent the day refilling the bottle , running a new purge line and going to the activation switch on the stick. It was so dam hot the kid couldn't top off the bottle.

dscott · #4 (**permalink**) 07-18-2006, 08:14 AM

I'm not quite sure what you mean by "dancing". If it wasn't wheel hop was the rear moving around on you? If that's what you mean I would check the bushings on the lower and the upper control arms. They are rubber and you may be getting some movement there. They can be replaced with poly but it does stiffen the ride.
Don

BCompy · #5 (**permalink**) 07-19-2006, 06:43 AM

Thanks Don I will check them. I heard and felt a clunk from the rear after I stopped from the burnout. Like the rear was catching up with the car. I will check the controll arm bushings ,that may be the slap I felt. Can't wait to see some of the video that was taken. I am told the launches appeared smooth with no wheel hop.

Was a proud moment to give a new Z06 fits!