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Sideways jolt when hitting the Go-pedel

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Old 12-28-2010 | 04:17 PM
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Default Sideways jolt when hitting the Go-pedel

So after playing with my fuel system and getting the car running right, i noticed one BIG thing. When i stab the throttle the rear of the car lurches right pointing car slightly left, so i have to compensate a little to stay straight. now if this was a big block mopar sure.... but wow. could it be a shock adjustment issue or other suspension issue?

when i got the car it ran funky, then i redid the injectors and such, and just not got it tuned, so it has never ran this well before so i cant compare it from before. its not a major jolt but you feel it in your *** for sure.

Duc
Old 12-28-2010 | 04:22 PM
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Duckman, check the rear lower control arms where they bolt to the rear cross member,
they get torqued to 140 ft/lb.

If they are tight then replace the lower control arm bushings that the 140 ft/ bl bolts secure

In inspect the upper control arms for worn bushings as well

also check that the shocks were not put back with the bevel washers missing this will make the lower hub slide front to back on the lower pin bolt
Old 12-28-2010 | 04:22 PM
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Note the rear wheels should look straight when looking at them from the top down
Old 12-28-2010 | 04:31 PM
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I think this is different then what Stan is referring to, but a loose big nut on the end of the stud that goes through the lower shock mount will cause a similar situation. This is on the outboard side of the lower control arm, out by the hub carrier. Make sure it's fully torqued, like what Stan says. I had this problem and the bolt was tight when I put an open end wrench on it, but the problem went away went I finally torqued it. It took another 1/2-3/4 turn with the big wrench.
Old 12-28-2010 | 04:33 PM
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Alsio check to see that both rear tires are the same size. Having one slightly taller will cause that.
Old 12-28-2010 | 04:46 PM
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Do you have LSD? Most of the non-LSD cars that I have driven do this to some extent. Mine included.

When you only have power going down with one wheel, sorta torques the car.
Old 12-28-2010 | 04:49 PM
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Originally Posted by atb
I think this is different then what Stan is referring to, but a loose big nut on the end of the stud that goes through the lower shock mount will cause a similar situation. This is on the outboard side of the lower control arm, out by the hub carrier. Make sure it's fully torqued, like what Stan says. I had this problem and the bolt was tight when I put an open end wrench on it, but the problem went away went I finally torqued it. It took another 1/2-3/4 turn with the big wrench.
+1 on making sure the lower shock mount pin is properly torqued - 109 ft lbs IIRC. If one or both sides is loose, the vehicle will yaw to one side... BTDT
Old 12-28-2010 | 04:51 PM
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Originally Posted by SeanR
Do you have LSD? Most of the non-LSD cars that I have driven do this to some extent. Mine included.

When you only have power going down with one wheel, sorta torques the car.
everything is tight and level, same tires etc. it is a non-lsd car. i figure that could be what i am feeling as well. thanks for all the help guys!
Old 12-28-2010 | 06:27 PM
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My car is non-LSD and it accelerates perfectly straight. I'd keep checking the assembly of the rear suspension. I've seen them misassembled. Here's what the big pin assembly order should look like.
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Old 12-28-2010 | 06:36 PM
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a good name of the feeling i get is torque kick.. heheheeheh maybe my shocks/springs are set to soft.
Old 12-28-2010 | 09:49 PM
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My bother's '83 auto non LSD never did that. Lift the end up and kick the tire, see if it moves more on one side that the other.

OR sinde yours is a 5-speed, could it be that you are breaking the tire loose?
Old 12-28-2010 | 10:03 PM
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Originally Posted by Imo000
My bother's '83 auto non LSD never did that. Lift the end up and kick the tire, see if it moves more on one side that the other.

OR sinde yours is a 5-speed, could it be that you are breaking the tire loose?
Breaking a tire loose has never made my open diff auto kick to one side or the other.

Case in point. ↓↓↓
Old 12-28-2010 | 10:16 PM
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Originally Posted by Bill Ball
My car is non-LSD and it accelerates perfectly straight. I'd keep checking the assembly of the rear suspension. I've seen them misassembled. Here's what the big pin assembly order should look like.

Thanks Bill. Any preference on which direction the conical goes in? Or will it make sense?
Old 12-28-2010 | 10:19 PM
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Originally Posted by Speedtoys
Thanks Bill. Any preference on which direction the conical goes in? Or will it make sense?
There is a concavity in either side of the hub carrier into which the cone fits.
Old 12-28-2010 | 10:27 PM
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Gotcha..it just 'makese sense' then.

Thanks!

After I finish my top-end, you up for torque conv seals and bearings with your trick?

I'll bring my smoker..can feed quite a party with it.


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