ok here is what i got. my car is making around 600 hp on the bottle. its a foot brake car with a 3600 stall. i have spohn ta,lca's qa1 single adjustables up front and starnge singles out back. a wolfe sway bay in the back with 6 springs. UMI sfc's.
ok here is how the car is leaving. im leaving at around 2400 rpms and the car hooks and begins to come up. it raises the front around 1 1/2 ft. then comes down and unloads the rear tires and spins. this car has been doing this for over a year now and i am very fustrated. it has cut some mid 1.30's in the sixty but most of the time its in the high 1.40's and 50's.
now i dont know that much about pinion angle, so right now im guessing its around nuetral. i have worked with the shocks front and back and nothing seems to help the car at all. i have even tried flashing the converter at idle off the line and it does the same exact thing. the car just hooks for a split second and then unloads the rear tires and spins.
this car has been 9.90's with it reacting like this, but i know there is more in it. if you guys have any advice i would greatly appreciate it.
__________________ Full weight street car with a little spray.
Location: In the garage, working towards a 2900 lb raceweight :D
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Sounds like the instant center is off, that's what usually what causes that. What angle are the control arms at compared to the ground? Where do you have the shocks set? What tires, air pressure? Do you have travel limiters on the front, and if so what kind of downtravel do you have it set to?
More detail needed.... but I'm going to guess, that the instant center is off and needs to be adjusted (lca angle wrong, or the front of the tq arm needs to be adjusted up or down) Shocks, I'd put the rears at 6 fronts at 3 (if you are running qa1 or strange both single adjustables)
Pinion angle isn't going to make or break this, I usually run mine about 1/2 a degree negative for referance, and have had good luck with it there.
Strapping the front end down (eliminating 1 to 2 inches of downtravel) may help alot as well, to get the car moving forward more and not coming up as much.... upward motion is wasted forward motion.
sounds like its on the ragged edge of hooking... here's some things you can do
add weight to the trunk
make the power come in smoother (progressor)
take a little pill size out
the car is capable of taking the hit... its just a fine line... you could find some one close by that knows how to set up a 4th gen.
Sounds like the instant center is off, that's what usually what causes that. What angle are the control arms at compared to the ground? Where do you have the shocks set? What tires, air pressure? Do you have travel limiters on the front, and if so what kind of downtravel do you have it set to?
More detail needed.... but I'm going to guess, that the instant center is off and needs to be adjusted (lca angle wrong, or the front of the tq arm needs to be adjusted up or down) Shocks, I'd put the rears at 6 fronts at 3 (if you are running qa1 or strange both single adjustables)
Pinion angle isn't going to make or break this, I usually run mine about 1/2 a degree negative for referance, and have had good luck with it there.
Strapping the front end down (eliminating 1 to 2 inches of downtravel) may help alot as well, to get the car moving forward more and not coming up as much.... upward motion is wasted forward motion.
Thats kinda what i was thinking was going on after giving this situation some thought. This is my buddy thats having the problems. We had the car out saturday testing trying to get his progressive dailed in on his N2O. The car hooks fine on motor but when the least little bit of power is added the car plants the rear tire really hard and unloads spins the tires for about 20 feet and sets back down in the rear then it gets on out. It really looks to me like the car has to much bite. I think raising the lower control arms would help and i cant remember if he has relocation brackets on them or not. But after thinking about it i think its definitly the Instant Center. I think if we could tame the bite down it would maintain traction all the way out. I know we arent overpowering the suspension, we only had the progressive set at 20% on a 2 second ramp with a 200 shot. The car has gone a 6.29 1/8 with hitting it with the full 200 about 40 feet out. All we could get saturday was a 6.55. He has the spoon TA. Are they adjustable in the front as far as the instant center goes?
Sounds to me like you just needs some tweaking of the chassis. I'd run your pinion angle at -2, make sure your lca's run at an uphill angle towards the front of the car, and get some better shocks. Strange double adjustables in the very least, AFCOs preferred. A torque arm upgrade would help. We can get you set up with virtually anything. Give me a call at the shop if you're interested. 225-673-3533
__________________ Steve @ Madman & Co. Racing for Tech support call 225-673-3533, PM, or e-mail mad_steve_08@techie.com
Hurricane Proof up to 80 mph winds
Sounds to me like you just needs some tweaking of the chassis. I'd run your pinion angle at -2, make sure your lca's run at an uphill angle towards the front of the car, and get some better shocks. Strange double adjustables in the very least, AFCOs preferred. A torque arm upgrade would help. We can get you set up with virtually anything. Give me a call at the shop if you're interested. 225-673-3533
Hes got the strange shocks in the rear and QA1's up front. It has a moser 12 bolt rearend i believe. But the car wont respond to any shock adjustments. Its got to be in the instant center i would think at this point. I dont know exactly what angle the control arms are at but i will try to find out.
Hes got the strange shocks in the rear and QA1's up front. It has a moser 12 bolt rearend i believe. But the car wont respond to any shock adjustments. Its got to be in the instant center i would think at this point. I dont know exactly what angle the control arms are at but i will try to find out.
make sure you set the pinion angle also. set pinion angle off the flat on the yoke of the rear end.. don't worry about drive line angle.
__________________ Steve @ Madman & Co. Racing for Tech support call 225-673-3533, PM, or e-mail mad_steve_08@techie.com
Hurricane Proof up to 80 mph winds
Hes got the strange shocks in the rear and QA1's up front. It has a moser 12 bolt rearend i believe. But the car wont respond to any shock adjustments. Its got to be in the instant center i would think at this point. I dont know exactly what angle the control arms are at but i will try to find out.
these cars are soo finicky on small tires that you could be close and not even realize it... this is our first FAST torque arm car so we threw alot of weight in the bumper so we could see how the car reacts... i'd advise doing the same thing.... it makes changes a little more noticable as fas ar tire pressure and shock changes...
__________________ Steve @ Madman & Co. Racing for Tech support call 225-673-3533, PM, or e-mail mad_steve_08@techie.com
Hurricane Proof up to 80 mph winds
Thanks guys for all the input. I think he found a grimlin that could be most of the problem. We will find out Thursday night i suppose. Got to try to get it rite before saturday. We are going to try to run it in a true street class heads up quarter mile. I really feel like the car has the power potential for some 6 teens in the 1/8 if we could get it to hook. I would love to scale the car out and find the center of gravity. I think that would be some useful info if he ever decides to really fine tune the car.
thanks for all the info guys. unfortuantly the race has been canceled for tomm. so we will have to just try it out next weekend. found a little problem in the TA earlier this week that may be the source of my problems. if that does not work we are def. going to try shock and lca adjustments. but anyway thanks again guys.
__________________ Full weight street car with a little spray.
car spinning! please help! 
-typical racecar 
