I know this is probably a dumb question for those who have had this or know someone who has and fixed it.

After 20 plus years of racing I have seen this and just assumed something was screwed up and never personally got envolved.

Yesterday I had this issue. I run 6,800 stall converter. So I have to zing the whells pretty good to keep from heating the tranny fluid.

I tried the burnout at 6000 like I did a couple weeks ago. First pass I noticed the moment the engine hit the rev limiter the tires would shake bad. I came back and found two cold cylinders. One was account a bad spark plug wire. The other was account a wire that was not on the plug well enough as these spark plug boots seem to be pretty difficult. So I though this will fix the slow ET and the tire shake as maybe it was due to the way the engine performed against the rev limiter.

Second pass tires still shake just as soon as the engine bumps the limiter. The miss seemed to be fixed. Might add the ET was better but, still not what it should be.

Raised the limiter to 7,500. The tires still shook at 6,000 and shook less at 7,500.

Now that I have fully bored you all to death. If you or someone you know had tire shake during the burnout what was the fix?

I fully would expect it to be the tires but they were fine a couple weeks ago. Old as the Mayflower but, did not shake.

Leon

This is a little off the wall, but could the wind have blown some of the VHT mix back to the burnout area?

Are you running tubes in them? If so maybe one of them has a tube folded up causing a heavy spot now I have seen this more than once, that is one of the reason I don't run tubes now The cure is to jack the car up off of the tires and let all the air out, rotate the tire several times and then inflate them slowly several times and let the air out after each time and then inflate them again and see if that fixes it, if not you may need to dismount the tires and remove the tubes so you can inflate them outside of the tire to straighten the folds out

Oh I don't know. It was windy and the guy sweeping the burnout box kept sweeping the gravels and dirt between the lanes. Then a Promod would blow the stuff everywhere. The guy needed a little coaching. But, that said, I have ran in a lot of crazy cituations and never had this issue before.

Don't run tubes. Should have mentioned that.

When was the last time you balanced the tires... a
video would show you if its a balance issue... but
from what your saying it is... gets better at higher
rpm/speed (its past the one frequency)

2 things come to mind
not enough water and air pressure.

Plenty of water as they were spraying the pit before I rolled in. The tire pressure was the same we had ran in the past. These tires were ran all year in 2010. If it were balance it should have been a problem then, shouldn't it?

I am wondering if they have broken a cord or something. They were smooth going up the track.

Leon

Quote:

---

Plenty of water as they were spraying the pit before I rolled in. The tire pressure was the same we had ran in the past. These tires were ran all year in 2010. If it were balance it should have been a problem then, shouldn't it?

I am wondering if they have broken a cord or something. They were smooth going up the track.

Leon

---

Since it was the first 2 passes I would still say
it was a balance issue.. the tires sat and get flat
spots from sitting then you go out and try to make
them round again and down track you have enough
centrifugal force.. balancing is cheap... JMO
I have a small bubble balancer that I use alot

Anytime I ever got shake in the burnout - I shifted to high and matted it. The shake went away with wheelspeed.

I RAN THE CAR WITH THESE TIRES TWO WEEKS AGO WITH NO SHAKE IN THE BURNOUT.

They may have sprayed too far back but, I didn't witness anyone else having the problem. I have a 4.10 gear and was tuning the engine 6,000 in the water don't think it was lack of wheels speed. LOL

The car is 4-link with wish bone. Checked all the bolts and shock bushing while I was repairing a broken anti-roll bar connection. Found this while getting the car ready to race over the winter. It was an old brake from 2010. The tires may have shook back then and broke the mount. Don't remember what happened last year much less 2010.

I'll try some new tires

I can't wait till it warms up to sport my cool t-shirt I got from Leon !!

Love that big back glass car

had same problem vibration at 6400 in burn box. then would be ok until 6400 in high gear around 1/8mile (bad vibration) then would smooth out for last half. What i found was a bent driveshaft

Just changed the rear gear. Maybe I should do some more looking.

Didn't you go from a 6.17 to a 4.10? Thats a huge difference in tire speed if all else is the same.