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ericsz 03-11-2010 01:59 PM

Body roll....help!!
 
I have just mini tubbed my 69 Camaro, I moved the leafs in 6" on each side and the shocks are now on the inside of the leaf springs in a straight up and down location, got it out for first time last night and the car now how a crap load of body roll. I don't have a sway bar or anit roll bar back there. what do some of you use to limit body roll?? Thanks, pictures are always helpful. Thanks in advance..

Robert Simpson 03-11-2010 04:06 PM

Re: Body roll....help!!
 
Eric you might have to put a extra leaf in the pas side spring. Also I am guessing that the shocks might not be tight enough or you might have to lean the tops of the shocks in slightly to help compensate for roll. Just a thought. I am sure when you get a couple pictures you will get more suggestions.

ericsz 04-05-2010 09:22 PM

Re: Body roll....help!!
 
Ok, so could body roll cause driveshaft/ujoint breakage? took the car out this weekend, and man it has some body roll. 1st pass car went down the track and 2nd pass let go of the button and KABOOM!! looks as if the stock style u joint strap broke and that was all she wrote, broke the pinion yoke ear and bent the driveshaft. So I am having a new one built with a 1350 yoke on it, think this will take care of the issue? and what is your recommendations to fix the roll? Anti roll bar? Thanks.

treessavoy 04-05-2010 11:15 PM

Re: Body roll....help!!
 
That sounds like a pinion angle problem. I had that problem until I increased the pinion angle to 4 degrees but that's on a Mopar.

Some of the Chevy guys can help you with the proper angle.

JimR

Tom Goldman 04-06-2010 07:21 AM

Re: Body roll....help!!
 
By moving the springs inboard , you have effectively reduced the spring rate . How, did ths happen? ...By increasing the lever ratio the spring sees working against it. ......you have more axle housing outside the spring now ,so when the chassis rolls on launch, there is more leverage against it ...............As was suggested ,you could add a leaf to stiffen the right side. ....You could also counter the roll by staggering the shock valving from side to side., if you have a good set of double adj. shocks. ........I would probably go with the anti roll bar,as it is the easiest for a racer to tune at the track. ...............Your pinion angle may be off ,but excessive roll could have allowed the pinion to twist up to the point of binding ........If it's a Cal track or slapper type bar , go with no more than the suggested 4 deg. .........I've done this to quite a few cars over the years and have seen the problem a few times, usually on higher hp,longer wheelbase cars. .............Tom

ericsz 04-06-2010 07:47 AM

Re: Body roll....help!!
 
Just to let you know the car is definately not a HP machine, it is a mild 406 runs 7.20's in the 1/8th with CE Slide a Links. Has the Ranchos out back that Calvert recommends for the Caltracs.

Robert Simpson 04-06-2010 11:46 AM

Re: Body roll....help!!
 
Eric, what Tom said is exactly how I see it. I would not think that your drive shaft or pinion hit the floor due to body roll. If it did you have MAJOR roll. My first thought, without seeing or knowing your car, would be to put a additional leaf on the pass side, tighten up the shock on the pass side. But make sure that you leave your bars loose when making these adjustments then re set you bars. Yes, a sway bar would help. I am just thinking of inexspensive things to try. I hope you get it working out for you. Maybe it was just one of those things as far as your drive shafts breaking? Build it better and go back at it. But check the gear in your rear end. When things like that break, in our cars, we have to check other things because it sets a harmonic through the drivetrain that could crack a gear, and cut the life down on parts. Hope this helps.

ericsz 04-06-2010 02:36 PM

Re: Body roll....help!!
 
one more thing to note, the rear shocks have also been relocated, they are now installed straight up and down and not in the stock style staggered position, would this have anything to do with it?

Tom Goldman 04-06-2010 04:04 PM

Re: Body roll....help!!
 
The loss of the shock stagger itself wont have an effect on the roll,but shock location has an effect on the damping ratio, vertical to roughly 5 deg front or rear angle will allow the maximum damping efficency of the shock . ....Angleing inward ,as factory Mopars are, will reduce the damping ratio at the wheel.....Don't over look the possibility of a loose or worn left front shock. ..the wider ,stock rear spring stance may have masked a problem that was there before....Tom

rayfin 04-06-2010 07:37 PM

Re: Body roll....help!!
 
What class does it run? I'd just put a panhard rod on it if rules allow.

ericsz 04-06-2010 10:48 PM

Re: Body roll....help!!
 
car is basically a bracket car, rules are wide open as far as suspension goes, would a panhard bar really take the roll out of it?

Tom Goldman 04-07-2010 07:39 AM

Re: Body roll....help!!
 
No. .Panhard bars are for lateral location. ................Tom

ericsz 04-08-2010 08:11 AM

Re: Body roll....help!!
 
Here is a picture of my shock mounted, I was wondering what it would do it I mounted another shock on the outside of each side, I would have 4 rear shocks, would this help the body roll? I think it would be pretty unique and cool if it worked just want some opinions...

http://i50.photobucket.com/albums/f3...hockmount2.jpg

http://i50.photobucket.com/albums/f3...hockmount1.jpg

XSTOCKER 04-08-2010 09:36 AM

Re: Body roll....help!!
 
I'd suggest pulling your springs out and have them checked for cracks, rearched and maybe add a leaf or two. The picture isn't the best, but the spring looks sacked out.Just my 2 cents.

Robert Simpson 04-08-2010 10:22 AM

Re: Body roll....help!!
 
Eric, if you can move the shock to the outside of the spring, I would think it would help. It will help dampen the roll. You might have to tighten the shock on that side more than you are used to. Also, if you have not taken your springs out and check the leaves and see if they have collapsed any, you might want to do that. Good luck with it.

Robert

ericsz 04-10-2010 09:50 PM

Re: Body roll....help!!
 
Checked the pinion angle tonight. Tailshaft checks 2 degrees down and the pinion checks 2 degrees up. The driveshaft angle sits at 0* is this a bad thing???

Tom Goldman 04-11-2010 08:32 AM

Re: Body roll....help!!
 
Quote:

Originally Posted by ericsz (Post 181221)
Checked the pinion angle tonight. Tailshaft checks 2 degrees down and the pinion checks 2 degrees up. The driveshaft angle sits at 0* is this a bad thing???

Yes! ........ Move the pinion angle to at least 2 deg down . ...As mentioned moving the shocks outboard might help with the roll. .....You still might just have to replace the springs, if it appears the ones you have now may be fatigued. .........Tom


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