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Bmod141
08-16-2017, 10:32 PM
Hey guys.

Spring in front, shock behind on both sides per UMP's great rules.

The issue I'm having is with this setup, if you jack up on the RR shock mount, it picks up the LR and minimizes hike. It does the same thing on the racetrack.

If I move spring on top of rear end, this issue goes away. If I take the shock off the back of the RR, the issue goes away.

I've been through every nut/bolt/heim and cannot find a single issue. You have to forcibly push down on the LR to keep it from behind lifted.. To the point of an 8/2 with 200psi rod pressure will not keep it on the chain.

This is a common setup for b mod guys and I don't see anyone else having this issue.

Has anyone else experienced this or have any clue as to what is going on?

Thanks.

Fox_hunter42
08-17-2017, 05:04 PM
spring slider binding?, shock bent

Bmod141
08-17-2017, 11:24 PM
Brand new slider. Then tried a few others as well. Multiple shocks.

Fox_hunter42
08-19-2017, 06:50 AM
panhard bar holding it?, when I ran my 3 link i had rr spring behind, shock in front. lr spring in front shock behind, progressive spring on pull bar with 15 degrees, j bar in hole on right side of driveshaft even with pinion shaft, 7" higher on frame on left side

Bmod141
08-21-2017, 12:05 PM
Fox, We have to run springs on the same location on each side. Pullbar must be solid.

I'm pretty similar on angle. 18-19*. 7" j bar rake. Middle of pinion as well.

Fox_hunter42
08-22-2017, 06:18 PM
bird cage type spring/shock mount or clamped? If I'm understanding, you jack up the right side of rear end, the left comes up too. If you move the rr spring or leave spring and remove shock the problem goes away?

Bmod141
08-22-2017, 09:56 PM
Wehrs clamp style bracket.

With both spring in front, if you jack up RR, it picks up the LR as well.

If you move spring to on top of RR, it doesn't do it.

If i take the shock off the back aide of the RR it doesn't do it either!

Ita very confusing. I'm sure I'm missing something but it's nothing I can find. Nor about 10 other people. On the race track, the LR thrust angle isn't able to overcome this force either, so the car won't hike.

badfast47
08-27-2017, 04:50 PM
One thing i didn't see you mention is what your lower bar angels are at and what springs you are using.

powerslide
08-27-2017, 06:11 PM
Both of the lower trailing arms mounts are same height? How are the springs angled?