How to keep the front end from NOT doing wheel stands??
10-25-2007, 08:50 AM
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How to keep the front end from NOT doing wheel stands?? So far over the past few months I have unfortunately dragged the rear bumper several times. At this point I don't know from one pass to the next whether its going to pull them 2 feet or 5 feet. And it has been consistantly pulling the front wheels up high all along on spray.
Here is a run down of chassis settings/setup
- 100 shot off the transbrake release it will go sky high, 200 on progressive does the same
- 29x10.5w at 10 psi
- 4.56 rear gear
- Th350 with a Coan 8" converter (flashes to about 5500 rpm)
- Front and rear Hal 12 way "R" series shocks
- Both fronts set at 8 clicks
- Both Rears set at 7 clicks
- Madman limiters set at 3 inches of travel
- Custom NRC anti-roll system
- Pinion angle set to -2 (custom torque arm and rear suspension from NRC)
- Race weight is probably about 3300-3400 lbs, dont know for sure as the scales have been broke at the track.
- I even have the 3 gallon fuel cell mounted in the front nose to add a little weight, along with the 4 stage dry sump setup and tank up front too.
- I am launching at 3200-3300 off the brake, and the nitrous comes on when the transbrake is released.
Here is a picture of the car from last weekend at Byron Dragway. This was on its way up to dragging the bumper with a 100 shot off the line.
While wheel stands are awesome to look at, I don't want to hurt more any parts. I have already slammed down hard to the concrete once, and thats enough. I want this thing to launch consistantly with any worries about doing this below. What can I do to fix this issue.....
Here is a run down of chassis settings/setup
- 100 shot off the transbrake release it will go sky high, 200 on progressive does the same
- 29x10.5w at 10 psi
- 4.56 rear gear
- Th350 with a Coan 8" converter (flashes to about 5500 rpm)
- Front and rear Hal 12 way "R" series shocks
- Both fronts set at 8 clicks
- Both Rears set at 7 clicks
- Madman limiters set at 3 inches of travel
- Custom NRC anti-roll system
- Pinion angle set to -2 (custom torque arm and rear suspension from NRC)
- Race weight is probably about 3300-3400 lbs, dont know for sure as the scales have been broke at the track.
- I even have the 3 gallon fuel cell mounted in the front nose to add a little weight, along with the 4 stage dry sump setup and tank up front too.
- I am launching at 3200-3300 off the brake, and the nitrous comes on when the transbrake is released.
Here is a picture of the car from last weekend at Byron Dragway. This was on its way up to dragging the bumper with a 100 shot off the line.
While wheel stands are awesome to look at, I don't want to hurt more any parts. I have already slammed down hard to the concrete once, and thats enough. I want this thing to launch consistantly with any worries about doing this below. What can I do to fix this issue.....
10-25-2007, 09:02 AM
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Shock setting is above in the main post.....fronts are at 8, rears are at 7.
Last edited by SMKN TA 95; 10-25-2007 at 09:28 AM.
Only way for me to get to a tighter limiter setting is to lower the car a little bit in the front.
10-25-2007, 09:19 AM
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I will check today as I just unloaded the car from the trailer. I should be able to go tighter as the suspension has settled over the past couple of days. If not, I'll have someone sit on the fender to get it lower.
BUT, is that going to cure this issue? Thats the big question...
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10-25-2007, 09:22 AM
#8
I told you to start at 3 inches. Tighten them up. Set the shocks at 0 and push down on the front end. After you set them then tighten the shocks. On the QA1s I have had to run them up to 12 because the valving isnt there to control the front end. Also 10 psi in the tires is a little low. Of course when you add air it will hook harder.
10-25-2007, 09:28 AM
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I told you to start at 3 inches. Tighten them up. Set the shocks at 0 and push down on the front end. After you set them then tighten the shocks. On the QA1s I have had to run them up to 12 because the valving isnt there to control the front end. Also 10 psi in the tires is a little low. Of course when you add air it will hook harder.
And when you said to set them at 3 inches, that did work for the first couple weekends
Then this past weekend the track had awesome prep and then up comes the front end again.
I would have to assume that I need to leave the pinion angle alone and the rear settings alone? Just tighten up your limiters in front and go much tighter on the shocks?
A friend of mine recomended that I lower the air pressure in the rear to help get more wheel speed to get me out of the gate without standing it up... Whats your opinion on that?
10-25-2007, 09:49 AM
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It is, and will be going down to a 4.10 this winter I think. Once I get a clean pass on the 200 I'll know for sure what gear I need. Currently going though the traps at 8300 on a shake down pass.
10-25-2007, 11:16 AM
#17
Next time you go I'd put the front shocks to full tight for the first pass, doing wheel stands like that will only end up ugly eventually. Changing the rear gear would be a safe move too to help some, especially if you're going thru the traps at that high an rpm already. Maybe try adding some delay to the nitrous. Try starting with a .3 delay, see what that gets you instead of hitting it right off the brake. With a converter that flashes hard like yours does, and leaving at 3400 it's got to be a real hard hit right out of the gate, a delay might do ya some good.
Tightening up the travel limiters will also certainly do some good. If you have to get a fat guy to lean on the radiator support or something
Also, what kind of angle are the lower control arms at, can that be adjusted to adjust the instant center some? I know when scotty had that car the nose would come up about a foot or so with a weak little 346 in it, now that it's got a real motor in it I am not totally surprised it wants to go to the moon.
Tightening up the travel limiters will also certainly do some good. If you have to get a fat guy to lean on the radiator support or something
Also, what kind of angle are the lower control arms at, can that be adjusted to adjust the instant center some? I know when scotty had that car the nose would come up about a foot or so with a weak little 346 in it, now that it's got a real motor in it I am not totally surprised it wants to go to the moon.
10-25-2007, 11:32 AM
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Next time you go I'd put the front shocks to full tight for the first pass, doing wheel stands like that will only end up ugly eventually. Changing the rear gear would be a safe move too to help some, especially if you're going thru the traps at that high an rpm already. Maybe try adding some delay to the nitrous. Try starting with a .3 delay, see what that gets you instead of hitting it right off the brake. With a converter that flashes hard like yours does, and leaving at 3400 it's got to be a real hard hit right out of the gate, a delay might do ya some good.
Tightening up the travel limiters will also certainly do some good. If you have to get a fat guy to lean on the radiator support or something
Also, what kind of angle are the lower control arms at, can that be adjusted to adjust the instant center some? I know when scotty had that car the nose would come up about a foot or so with a weak little 346 in it, now that it's got a real motor in it I am not totally surprised it wants to go to the moon.
Tightening up the travel limiters will also certainly do some good. If you have to get a fat guy to lean on the radiator support or something
Also, what kind of angle are the lower control arms at, can that be adjusted to adjust the instant center some? I know when scotty had that car the nose would come up about a foot or so with a weak little 346 in it, now that it's got a real motor in it I am not totally surprised it wants to go to the moon.
I have a feeling once I tighten up the limiters and the shocks more that it will fix it. To get where I want to go with the car, I need to leave with close to 200 off the brake. I know I will get there, it just takes time and alot of fine tuning.
As for the rear control arms, I cant say that I have looked at them lately. As for changing anything on the rearend, that I dont know if I want to touch just yet. The rear is working, as it went 1.29 so far in testing.....but that was with the front tires about 2-3 feet in the air past the 60' mark.
Im gonna mess with the shocks and limiters tonight...
10-25-2007, 11:36 AM
#19
Ya someone else was having this problem.. I think it was Noyzee. He ended up setting a delay on the nitrous to 1/10 after he launches. I believe that it did work for him.
Definitely change the rear gear and that will prob help the most right there.
Definitely change the rear gear and that will prob help the most right there.