shaun

hey guys im haveing a wheel hop problem.
the car is a 98 Z28 a4 and is puting down about 350hp at the wheels since i swaped intakes and the suspention mods are lakewood lca's,edelbrock aj tq arm set at -1/2 degree,bmr lca brackets set on lowest seting,bmr aj phb,
hyper coil springs and bilstien hd shocks,nitto 275/40/17 dr's.

the car just wheels hops a few times when i do a burn out and when i try to launch and in turn will make me start spining.
what should i do to fix this?
im thinking i need more neg pinion angle and from what i read on here it needs to be about -2.5.

MattysTA

iTrader: (18)

whats the tire pressure at? make sure they arent overinflated as that will cause wheelhop..
i would also set that pinion angle to about what you said

BMR Tech

iTrader: (9)

Sounds like you are not doing a good enough burnout IMO...

BlackScreaminMachine

iTrader: (17)

I cannot use FQuick at work,

What tires?

What Stall if any?

also Burnout seems to be sorely lacking. Get more water on the tires and invest in line lock, it helps with auto's too.

12secSS

iTrader: (30)

A couple of issues:

1. Torque Arm Pinion Angle = -2' - -2.5'
Being at -.5 is allowing the torque arm to go positive under launch conditions, which unloads the rear axle.

2. Relocation Brackets = 2' upward slope, going from the rear of the car to the front.
If you are not lowered, you do not need to be at the lowest bolt hole for the Relocation brackets, this can cause binding in the suspension. Try using the middle hole if you are at stock ride hieght.

3. Burnout Technique: What is your burnout technique?

4. Launch Technique: What is your launch technique?

5. Setup Specification: Tells us about your setup in more detail, tire pressure, rpms, etc ...

Only change one thing at a time to find out what helped and what did not.

shaun

the tires are 275 40 17 nitto drags.
car is lowered with hypercoil springs and bilstien hd shocks.
for the burn out i will go around the water box then back in to the eadge of the water box then drive foward a foot or so and hold the brake down not all the way but enough to hold the car but no more than that then i go to about 3/4 throttle and try to hold it to about 3500-4k rpms for about 5-6 seconds.
im going to put the car up on a drive on lift tomorrow and adjust the tq arm angle.
point me in the right direction guys and thanks

when im launching i will foot brake the car to about 1200 or so rpms till it feels like the rear of the car wants to start moving then on green i will go wot not 100% instantly but close i try to get a feel if the car will hook or not so that varys a bit.
ill start at about 20 for tire psi and maybe go down to 18 but lowering the tire psi dont seem to help that much.

MattysTA

iTrader: (18)

nittos require a serious burnout to get good and sticky. keep the burnout going till you see a decent amount of smoke. 18-20 psi is what i used to run in mine so thats ok. aside from the pinion angle that seems to be all you need to do.....

BlackScreaminMachine

iTrader: (17)

Get some line lock for the car, do a better burn out. If you use the line lock and get the tires wet, the brakes will not be heated up and you wont creep past the lasers. Some more pinion angle will not hurt.

JL ws-6

iTrader: (50)

[QUOTE=12secSS;11474267]A couple of issues:

1. Torque Arm Pinion Angle = -2' - -2.5'
Being at -.5 is allowing the torque arm to go positive under launch conditions, which unloads the rear axle.QUOTE]


Wrong

Tq arm cars do NOT suffer from leafspring wrap, and a negative 1/2 degree of pinion angle is NOT going to cause the rear to go positive


This kind of advise is exactly what the thread starter does not need to hear.

You have wheel hop becuse the tires probably aren't wet enough, and you aren't getting them up to speed fast enough.

You need to put a line lock on teh car, spin the tires in the water so they are WET.

Pull foreward, set the line lock and get on it HARD and get the car in 2nd gear as fast as possible, once you see smoke give it a 5 count and turn off the line lock and power thru the burnout. If you go past the tree screw it back up and restage the car.

I can't even count the # of times at the track I have seen people not do the burnout procedure right, and then end up with the car leaving all screwed up and they wonder why.

You may, not need the control arms in the bottom hole, but that is not going to cause the car to wheelhop, and is NOT putting the rear suspension in a bind. It will if anything make the car hit the tire too hard and make it fall on it's face, possibly unload 30 to 50 feet out and spin, but not wheelhop.

shaun

im going to try and put the control arms on the middle hole and see what that does.
and for some reason my car wont do a huge smokey burnout i only get a little tire smoke.
i was at the track and only made 2 runs and i paid more attention during my burn out and i was holding it to about 4k rpms in 1st but i never thought about going in to second i thought that was ony for drag cars.
thanks for the help jl ws6vand with the info i just gave help me see what im doing wrong lol so let me see the light lmao.
this is starting to **** me off and it seems no matter what i do i cant get any better times

shaun

bump.

JL ws-6

iTrader: (50)

Even if the car doesn't shift into 2nd, get the rpm's up to 5000 and hold them there for a good 8 to 10 count. That will be enough, just get the linelock on the car and when you're done with the burnout, turn it off and stay in it until you hear/feel teh car grab/screetch the tires.

Then you know that you came out spinning and they're hot/clean and ready to go.

I laugh every time I see someone get in the water, do a burnout in the waterbox, then stop spinning the tires before they are even out of the water tracks.

Happens all the time, and that's a good recipe for 14 second passes with a 12 second car.

z28rob18

iTrader: (7)

yea you really need to get the tires spinnin lik jl said. a quick spin in the water pull up set the line lock and burn them good. i didnt realize how shitty my burnouts were till i got the line lock (m6) i finally was able to get a decent smokey burnout and get some ok 60' times

JL ws-6

iTrader: (50)

Exactly. Spin them in 1st in the water quick, pull up and stop about 3 feet out of the water. Set the line lock, put the car in 2nd and MASH it.

I usually (with the TH400) get the tires spinning quick in 1st then quick pull 2nd and mash it, hold it at 6500 or so for a 4 to 6 count (6 on the first run, 4 the rest) and then turn the lne lock off and stay in it until it grabs.

No problems.

I have started the burnout before in 2nd, and have shifted to 3rd before as well, but I generally find it's not needed.

shaun

ok thanks for the tips guys ill give it a try when i get to the track this week end coming.