rebski
Veteran Member
The car. 1970 RS/SS
Gen I 350 kind of rowdy lots of fun. Trans TKO-600, rear 12 bolt 3:32 gear Posi.
Chassis is mostly stock with Energy Suspension mounts and bushings new springs front and rear, 5 leaf out back from General Spring. The leaf's are the heavy duty Camaro/firebird/nova rated at 147lb per inch.
Now to the issue, the car goes down the road smooth as glass in all gears only been up to 100mph.
When I get hard on the throttle (in the secondary's ) the gearshift rattles to the extreme. First through fourth.
Checked angles this is what I got with the car on a drive on lift. During the check I pulled the driveline and took the angles from the trans out put shaft and put a socket on the pinion nut and checked there and the yoke.
Trans 2.5* down it is as high as it will go and not hit the tunnel, driveline 0.6* down, Diff 0.6* up. these are corrected figures the rack was 0.3* down to the back of the car.
Center of trans output shaft is only 1/2 inch higher from the ground than the pinion shaft.
I have read a lot of the posts about this. I think that the leaf's are wrapping up and creating an intersect in the rear and possibly the front joints under hard throttle. I have read that you can get 3-5* of wrap from the diff.
What I am looking for is some input on how much shim to put between the housing and the leaf's from some of you who have been down this road. I am thinking a pair of these shims to point the diff down. 2*for1.4* or 2.5*for1.9* or 3.0*for2.4*.I know if I go to far I should start getting a deceleration vibration.
The more I point the diff down should net some more angle on the driveline itself which should be good.
Thanks for any help you can give.
Gen I 350 kind of rowdy lots of fun. Trans TKO-600, rear 12 bolt 3:32 gear Posi.
Chassis is mostly stock with Energy Suspension mounts and bushings new springs front and rear, 5 leaf out back from General Spring. The leaf's are the heavy duty Camaro/firebird/nova rated at 147lb per inch.
Now to the issue, the car goes down the road smooth as glass in all gears only been up to 100mph.
When I get hard on the throttle (in the secondary's ) the gearshift rattles to the extreme. First through fourth.
Checked angles this is what I got with the car on a drive on lift. During the check I pulled the driveline and took the angles from the trans out put shaft and put a socket on the pinion nut and checked there and the yoke.
Trans 2.5* down it is as high as it will go and not hit the tunnel, driveline 0.6* down, Diff 0.6* up. these are corrected figures the rack was 0.3* down to the back of the car.
Center of trans output shaft is only 1/2 inch higher from the ground than the pinion shaft.
I have read a lot of the posts about this. I think that the leaf's are wrapping up and creating an intersect in the rear and possibly the front joints under hard throttle. I have read that you can get 3-5* of wrap from the diff.
What I am looking for is some input on how much shim to put between the housing and the leaf's from some of you who have been down this road. I am thinking a pair of these shims to point the diff down. 2*for1.4* or 2.5*for1.9* or 3.0*for2.4*.I know if I go to far I should start getting a deceleration vibration.
The more I point the diff down should net some more angle on the driveline itself which should be good.
Thanks for any help you can give.
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