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View Full Version : New suspension. Ride height issue. Front is level. Rear is off over 1" side to side


Nicks67GTO
03-31-2014, 04:18 PM
Title says most of it.

Iv'e got the SC&C stage II setup with Ridetech HQ's, SC&C spec'd SPC springs, Currectrac RCA's and Hellwig chassis mounted swaybar on a moser 9" Rear and ABC aluminum body mounts. The frame was fresh off the frame shop rack, straight as an arrow and practically fell in. Its not tweeked. The rear axle is located perfectly front to rear in the 1/4 panel openings.

The front of the car is pretty much level side to side. A touch high on the passenger side but I think its off because the back is way off and its pulling everything up with the boxed frame. Anyhow Iv'e measured about everything. The car structure seems like its all spot on. I measured shock compression and there's over 3/4" difference at ride height between the two rear shocks. The only other thing i'm seeing is a difference in rear compressed spring coils center to center at ride height. Its compressing well on the driver side and not on the passenger side. Like 1/4" per coil difference. 5 coils and you have 1.25" The back doesn't seem like its binding, everything is well lubed, was tightened at ride height iv'e swapped springs around side to side, that didn't help so i cant imagine its mismatched springs.

It seems like its got to be mildly binding enough to not allow it to settle but I can push it below ride height. Im kind of at a loss. I think tomorrow i'm going to go loosen everything up, unhook the rear swaybar and cycle it some more to see if that does anything.

Anyone got any other suggestions? I'm kind of thinking out loud and I wont be able to call Marc until a bit later in the day.
andrewb70
03-31-2014, 06:53 PM
Does the driver's rear sit lower?

Andrew
Nicks67GTO
03-31-2014, 07:33 PM
Does the driver's rear sit lower?

Andrew

Yes by about an inch, maybe a touch more, though the driver side looks like I expected it to. It seems like it isn't necessarily the drivers rear sitting low but the passenger side rear sitting very high.
andrewb70
03-31-2014, 08:23 PM
I have read about this and many refer to it as the "a-body" tilt. There doesn't seem to be any consensus as to what might be causing it, but people have addressed the problem by using various shims, etc.

You might want to double check your rear springs and make sure that they are installed the same. I see you have a Moser 9". Does it use the early a-body bolt in style springs or the later style springs?

Andrew
fast98
04-01-2014, 03:03 AM
My 67 Camaro is the same exact way.
SSLance
04-01-2014, 03:45 AM
I'd unhook sway bars, unhook shocks, jounce the car around a bit and check again. Measure from the frame to the ground at certain points on both sides for reference. Also, make certain that the ground the car is sitting on it completely level before you start.

It is very difficult to diagnose where the issue is until you weed out all of the variables. Is the rest of the car complete and done (all of the weight that is going to be installed...installed)?

The front ride stance can and will affect the rear and the rear will affect the front.
Nicks67GTO
04-01-2014, 05:10 AM
I'd unhook sway bars, unhook shocks, jounce the car around a bit and check again. Measure from the frame to the ground at certain points on both sides for reference. Also, make certain that the ground the car is sitting on it completely level before you start.

It is very difficult to diagnose where the issue is until you weed out all of the variables. Is the rest of the car complete and done (all of the weight that is going to be installed...installed)?

The front ride stance can and will affect the rear and the rear will affect the front.

I might even loosen the body mounts since I did swap frames. the garage I did it in dosent have a level floor. I'm wondering if I didn't torque it in kind of funny? The rest of the car is all put together except for a few pieces of trim and the front bumper.
andrewb70
04-01-2014, 05:18 AM
I might even loosen the body mounts since I did swap frames. the garage I did it in dosent have a level floor. I'm wondering if I didn't torque it in kind of funny? The rest of the car is all put together except for a few pieces of trim and the front bumper.

You can make your own leveling pads using a laser level, some 2x4s and thin vinyl floor tiles as spacers.

Andrew
SSLance
04-01-2014, 05:42 AM
If you don't get all four tires on a square level plane, you are just chasing your tail trying to level out the ride height, been there, done that. You also need to make sure the front suspension isn't in bind by either having slip plates under the tires or rolling it back and forth after letting the car down from a jack. Loosening the body mounts might help as well.

Start at the bottom and work up. Tires on a level plane and relaxed, 4 corners of suspension relaxed not in any kind of bind, anything that can restrict ride height disconnected (sway bars, shocks etc), body set down on body mounts in a relaxed state (check for any gaps between body mounts and body) and finally all of the ride height weight in place...then work from there snugging things back up once you get things leveled out.
Nicks67GTO
04-01-2014, 04:14 PM
Well to update I found that the front was way off too. For some reason I thought it was about level but I was dead wrong. It was off about an inch as well. I found the passenger side coil spring was clocked wrong and wasn't sitting properly in the coil pocket. I fixed that and now i'm within a half inch in the front side to side. If I get to 1/4" i'll call that good. I'm going to check tire pressure tomorrow as the driver side looked low. That might actually get me within 1/4"??

Clocking the coil spring in the front seemed to help the rear out too. I'm now down to 3/4"-1" difference in the rear as opposed to 1"-1.25" yesterday.