Launch question/Going left

[Ed Carpenter]

Looking for some causes for my car starting to go dead left at the hit. It was fine and now 3 straight passes in a row I let the clutch out and it went left. And I mean left. The last run I think I could of reached out and touched the tree as I went by. We have touched nothing on the car on the rear. We have limited the front end travel to prevent eccessive wheel stand. I broke the pinion gear fri night so i have the rear apart and found nothing to cause the left hand turn. Nothing is broke on the suspension. The shocks are ok(ive had that problem in the past) On another note. My daughter videotaped the car fri night and when i did the burnout the right tire was spinning but no smoke on the burnout. The left tire had smoke pouring off of it. the axles are fine. I'm not sure what is going on here. Thanks. Ed

[Darrin Christen]

Not sure why one tire was smoking and not the other, but if that was indeed the case I could see where more heat in one tire versus the other would make the car launch to one side or the other. How was the water in the burnout box?

[Jeff Lee]

That's what my AMX was doing. I checked EVERYTHING I could. I adjusted EVERYTHING to compensate. Nothing. In the end it was the driver side floor had moved up an inch and a half.
I know another racer that had the same problem. All sorts of 4-link pre-load to straighten it out. In the end...bad front spring.

[Ed Carpenter]

I guess I should have added it's a ladder bar car. Darrin nothing unusual at the water box. Did it the last two runs at Crandall and the 1st pass in San Antonio so that probably isn't it. I don't have video of the Crandall runs but even on DRC they mention how far left I went out to the wall before I had to real it back in. Ed

I have the run from behind in San Antonio. I just don't know how to get it from my video camera to here for you guys to see it. Ed

[al wisniewski]

Ed,did you check your axle tubes? bent or twisted? Usually when a car starts doing funny things all of a sudden ,it could be a dead spring or bad shock. The preload went away so look close at the bars. Stretched rod end? And square the car up to make sure something hasn't settled .

[Tom Goldman]

Assuming no one else has issues with the track, Everything Al stated in the previous post is a possibility . ..............I would start with the axle brackets ,stringline the rear to see if it's straight in the car . .................If the rear is straight ,I'd check the shocks to see if one is bound up , probably the left rear .............................I just re read your post and the part about the burn out reminded me of a friends car . ....It had a set of axles that looked ok, but had actually stripped the splines in the spool just enough to spin under load..........Don't overlook anything. .......Tom

[Wade Mahaffey]

Check the ladder bar brackets on the rear housing. Sometimes the holes will enlongate (oval) from a loose bolt condition. This will allow the preload to change at the "hit". If this is the case, simply make some sleves about 3/8" long that fit the bolt fairly tight with about a .250 wall thickness. Weld (TIG) them to the ladder bar brackets (one for each hole, 8 total). Take the time to determine the correct location of the sleves to be welded in place. You can use the undamaged bracket to comfirm the proper hole location. Use a pair of dividers (dividers: as in a device/tool used to draw a circle, only using the points to determine location instead of a tape measure). After the fix, reset the preload and confirm at the track (compare tire temps after the burnout).
There could be a shock issue, or a tire issue but these things usually will cause a slight drift in one direction and not a consistant hard move. However, you will need to make shock adjustments a few times each season. This will compensate for normal wear of the shock, most of which happens in the trailer during transport.

Wade Mahaffey

[Mike Pearson]

I agree with Wade. I had the same problem with my car. It was the front hole on the ladder bar mount that was worn out. I fixed it by adding a plate with the correct size holes welded to the front ladder bar mount. Just a slight bit of slop in the holes will cause some crazy results. My car would cross lanes.

[04BlackSilverado]

Could a bad tire on the left side, cause the better right tire with traction, to push the car left?

Can you swap the tires and see if it pulls to the right to verify?


Newbie with a guess for what it's worth... Good luck.

[Ed Carpenter]

Ok I took it all apart today. First i will admit I'm not an expert on suspensions. I'm still learning so bear with me.

Shocks are ok. Not broke or bound up

No broken welds or cracks

Axle tubes are not bent or twisted

Axles are ok

However on the passenger side the ladder bar bracket that mounts to the axle tube both holes upper and lower are eggshaped. You could grab the ladder bar and move it a little bit when it was mounted in the car. The drivers side you could not move at all. That side the holes are still true with no eggshape at all.

Also this may be where the prelaod comes in im not sure but on the drivers side where the ladder bar mounts to the bracket(rear) the upper heim joint has 5 threads showing with the bottom showing 9 threads. Now on the passenger side the upper has 2 threads and the bottom has 6. I'm no expert but doesn't the top one set the pinion angle only? Why would they be different? Isn't the bottom one used to set the housing straight in the car. Again I'm no expert I want to learn all this for future use. Thanks for all the input. Should i string the car from the front crossmember to the front mounts for the ladder bars? Ed

Also this is how I bought the car. If it's all jacked up I want to fix it right.