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imca37
01-21-2014, 05:16 PM
What is the difference in location of where the j bar mounts to the pinion and the j bar mounts to the frame? Is the chassis mount supposed to be in line with the pinion mount/ J bar running parallel with the axel? Or is the chassis mount supposed to be ahead of the pinion? If ahead of the pinion, how much? Thanks

washeduptoo
01-21-2014, 09:06 PM
The chassis is usually ahead of the pinion, not sure exactly how much though. If its a 4link, the rear end will move forward as the rear end thrust. Best of luck.

Anonymous24
01-22-2014, 02:49 PM
Very good question! Usually the chassis mount is ahead of the pinion. You may need to use spacers to properly compensate bind issues during rear suspension lift and dive, including chassis roll. Easy way: lift car so all 4 wheels are at maximum travel. Measure J-bar angle. Set car on ground and have a few people stand on front and rear bumpers. Measure J-bar angle. Use spacers and bolts to adjust against binding. Also a good idea to round the bottom of the bolt head where bar mounts to pinion plate.This is my opinion. What works for one car may not work for another.

imca37
01-22-2014, 03:08 PM
Sounds good. I'm gonna make a spacer for the chassis mount to move it back a couple inches and see what happens

Anonymous24
01-22-2014, 03:25 PM
Sounds good. I'm gonna make a spacer for the chassis mount to move it back a couple inches and see what happensBe sure you make it out of some real durable material. The amount of load that bracket endures is massive. I have seen the chassis where to mount connects ripped completely away.

setup479point2
01-22-2014, 08:58 PM
Sounds good. I'm gonna make a spacer for the chassis mount to move it back a couple inches and see what happens Pretty sure if you do this you'll bend or rip the chassis mount out. I wouldn't do it . Better to rebuild the chassis mount , or if its a built chassis they have it where it needs to be already .

wisdirtfan
01-23-2014, 10:37 AM
You can weld another piece of 2 inch to the back of the existing mount on the chassis and use longer bolts on the clamp. I did this on our late model and it worked fine for the last 2 years didn't crack or rip at all and trust me the car got abused plenty lol.

imca37
01-23-2014, 11:12 AM
Yes if I were to space it that is exactly what I would do, weld another piece of 2x2 and use longer bolts. The real question is if I only knew what the optimal distance this mount had to be in front of the pinion I would be golden. Anybody know?

Confused?
01-23-2014, 05:53 PM
About 2-1/2 inches, centerline to centerline of the heims with the frame mount being ahead of the pinion.

setup479point2
01-23-2014, 09:29 PM
You can weld another piece of 2 inch to the back of the existing mount on the chassis and use longer bolts on the clamp. I did this on our late model and it worked fine for the last 2 years didn't crack or rip at all and trust me the car got abused plenty lol. If you do it this way it should work , you're rebuilding the chassis mount.

imca37
01-24-2014, 07:07 AM
2 1/2 inches. That's the answer I was looking for. Thanks and Welding a piece of 2x2 to the existing 2x2 should get me where I need to be. Thanks everyone

Lizardracing
01-26-2014, 08:56 PM
In my opinion the panhard bar should be parallel the the axle centerline when the axle is blocked up to simulate the attitude of the axle when in race conditions. This put the least amount of fore/aft loads on the pinion are as well as twisting on the chassis mount. 2.5" is likely a good rule of thumb however you should measure your car for accuracies.