Sloppy burnouts

[underdog]

OK got a new transmission, went back to my old converter, set my pinion angle back to -3°.

Now the Chevelle gets crazy sideways on the burnout. My weights are LF 779 RF 645 LR 682 RR 683 130# rear coil over springs with a ladder bar setup. The rear is square with the frame rails and I'm running 10 PSI in the rears

It leaves straight at the lights but after the water box it takes a very hard left turn. What gives

[BERT]

It sounds like you may need more wheel speed for your burnout.

[underdog]

That's really hard to do when I'm headed for the wall. My line lock is on my whell and I can't hold the button and crank the wheel at the same time. Stock 68 Chevelle with no power steering.

I don't know what has changed, other than the pinion angle ( It was way off like +5° ), It didn't used to do this

[ComaxRacing]

I agree with the wheel speed, if you have any misalignment in your diff a burnout at low RPM will find it. Measure to see if everything is square in the read end.

I've always been a fan of a hard and fast burnout, get in and get out fast, not a big fan of the slow, low rpm burnouts.

IMO

Corey

[underdog]

I like the "John Force" burn outs myself. I usually spool it up to 6K

I just pulled the front drums and one of the wheel cylinder plungers on the right front had come out and was jammed in the springs. So only one shoe was working on the right front.

This is one time I'm glad my junk is kinda slow.

Went red second round yesterday by the way !

[ComaxRacing]

Sounds like that front brake issue was the problem. Do you think you wnt red because of the brake problem?

Corey

[underdog]

That's my excuse

I just didn't have my head in the game. I didn't get a good burn out, was running the track champ. The car rolled and I put two bulbs on him, then I couldn't get the car in reverse, and when I did he staged

I was just a mess. I know red is red but it was a .016 and I would have run out anyway. I ran a 55 on a 57 dial and he was right there at the trap

But like a say alot, Next week will be better

[want-a-be]

OK got a new transmission, went back to my old converter, set my pinion angle back to -3°.

Now the Chevelle gets crazy sideways on the burnout. My weights are LF 779 RF 645 LR 682 RR 683 130# rear coil over springs with a ladder bar setup. The rear is square with the frame rails and I'm running 10 PSI in the rears

It leaves straight at the lights but after the water box it takes a very hard left turn. What gives

Not doubting you on anything. Just wanting to know how you checked it. How did you check how square the rear end is with the chassis?

Does sound like you're onto the problem with the brake problem though.

Don

[underdog]

On the pinion I used a digital angle finder on the harmonic balancer and on the pinion yoke and subtracted the difference then I also measured the drive shaft angle and pinion angle with the car level and weight on the tires.

I checked the rear by measuring from the sub frame back to the lower attach point of the ladder bar. I also measured diagonally from those same points.

I also have equal measurments from the brake backing plate to the frame rails on both sides of the car.

It hasn't been very long since it came out of the shop that fixed my broken diagonal link attach point and the car was squared by that shop but I don't know thier methods.

[want-a-be]

I was just curious as to how you checked how the rear end is perpendicular to the frame.

Myself, I have 2 six foot long pieces of 1" square tubing made of aluminum. I clamp them onto the axle flanges or the brake hobs. Then plumb bob them to the floor. Find the center of the chassis and plumb bob it to the floor. Then measure how close each side is to the center of the chassis.

Using the longer square tubing like this will take a very small difference between the difference of the rear end not being square and magnify it by a lot longer ratio.

Don

[underdog]

Don,

I understand the 6' tube and don't mean to sound simple but how do you come up with the center of the chassis ? My frame rails are somewhat curved so it depends on where I measure from

[ComaxRacing]

If its a ladder bar you can hang a plumbbob from each bolt hole on the chassis where the ladder bar bolts into. Make sure you hang the plumbbob the same way on both sides. Take a peice of masking tape and tape the floor across the two bobs. Find the center between the two, make a mark on the tape, then put one plummbob on that point, (usually there is a cross member).



Corey

[underdog]

Thanks

I checked it your way and it comes out the same as the way I did it

I'm sure my front brake was the problem. Did some burns in the driveway and everything seems back to normal now

[Skunkworkx]

Is your posi going bad ?

[underdog]

Nope, I run a spool

Ran the car today and it hooked up fine. Nice "John Force burn outs" but I'm back to the same old lean misfire. I went up 6 jets front and rear but it's still breaking up. Plugs still look lean.

I lost first round by .001 If it would have hit on all 8 just one time I would have beat him.

Oh well, always next time

[Skunkworkx]

Nope, I run a spool



I guess it was the track ?

Spool here too and one thing I've noticed is to keep and eye on the lugnut torque setting :o

[Awesome Bill]

Nope, I run a spool

Ran the car today and it hooked up fine. Nice "John Force burn outs" but I'm back to the same old lean misfire. I went up 6 jets front and rear but it's still breaking up. Plugs still look lean.

I lost first round by .001 If it would have hit on all 8 just one time I would have beat him.

Oh well, always next time

Are you sure your running enough timing? The lack of it will pop all the way down the track, Usually does not hurt anything.