1967 Camaro Heidts Pro-G subframe ride height too low. Help!!

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139422139418139415139419139416139420139417I'm just now getting my pro touring Camaro to the point where I can drive it and really tune the suspension. It has a Heidts Pro-g front subframe with their 2 inch drop spindle, (the only spindle they offer). I installed their recommended springs which are Viking 10dp500 and their base shock, a cb-160 single adjustable . the shocks are 15.75 extended 10.75' compressed. The ride height of this setup is just too low for me. The first thing I tried was cranking up the pre-load to gain some ride height back. This resulted in a really harsh ride I couldn't stand. My research indicated the extra preload was the cause of the harsh ride. Next, I took out all of the pre-load and built 1 inch spacers to go between the shock and lower control arm, effectively making the shock an inch longer, this solved the ride height problem and most of the harsh ride problem, ( it rides much better but still a little stiff). My main concern now is contrary to Heidts instructions, the lower control arms which should be level, are substantially below level which does the steering geometry no good. I believe the proper and perfect solution to my dilemma may be different spindles with less drop. Any help would be greatly appreciated. Thanks, Bill

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I'm just now getting my pro touring Camaro to the point where I can drive it and really tune the suspension. It has a Heidts Pro-g front subframe with their 2 inch drop spindle, (the only spindle they offer). I installed their recommended springs which are Viking 10dp500 and their base shock, a cb-160 single adjustable . the shocks are 15.75 extended 10.75' compressed. The ride height of this setup is just too low for me. The first thing I tried was cranking up the pre-load to gain some ride height back. This resulted in a really harsh ride I couldn't stand. My research indicated the extra preload was the cause of the harsh ride. Next, I took out all of the pre-load and built 1 inch spacers to go between the shock and lower control arm, effectively making the shock and inch longer, this solved the ride height problem and most of the harsh ride problem, ( it rides much better but still a little stiff). My main concern now is contrary to Heidts instructions, the lower control arms which should be level, are substantially below level which does the steering geometry no good. I believe the proper and perfect solution to my dilemma may be different spindles with less drop. Any help would be greatly appreciated. Thanks, Bill Does anyone have anyone have any input?

[bret]

What does Heidts have to say about it?

Can you post an image of the front suspension from a front view so I can see the relationship of the control arms and the position of the coilspring? That would help us determine a path to resolution.

[sticknstring]

What does Heidts have to say about it?

Can you post an image of the front suspension from a front view so I can see the relationship of the control arms and the position of the coilspring? That would help us determine a path to resolution.
Hi Brett, I'll post a front photo when I can. It will probably be Monday though. Heidts says that I have the only spindle available for the pro-g and they are the 2 inch drop. I think 1 inch drop would be perfect. They had no other answers for me.

[Shawn01754]

Fiberglass hood? What motor? Maybe you should weigh the car

[dontlifttoshift]

If you only need an inch, there is enough range in that suspension to accomodate.

Preload has nothing to do with ride quality _as long as_ the shocks are not topping or bottoming out and the coil spring isn't binding.

When you take that picture, take another picture with a tape measure from the ground to the lower control arm bolt and from the ground to the lower ball joint.

[dhutton]

In my amateur experience a lot of spring preload without enough rebound damping on the shock will lead to a lousy ride. Have you tried increasing the rebound damping on the shock?

Don

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My amateur experience is the same here Don. These shocks are Heidts cb160's that are only single adjustable and I've been told they are only rebound adjustable. The ride is just tolerable with no preload and the shocks set on the lowest setting. It get worse with and preload or dampening adjustment. As far as the engine is is an aluminum ls1 with Vintage air and Tremec 5 speed and a steel hood. I'll weigh the car when I get an opportunity but there are none near me. I will get photos of the a arms maybe tomorrow. I really appreciate all the answers and input here you guys! Thanks,Bill

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Here are some photos, sorry they are upside down. I think I was lucky to get them here at all! Hope this provides enough info.Thanks, Bill

[Peter Mc Mahon]

Edited after re-reading

[stinger67]

Bill, I'm just getting my 67 up and running with most of the same set up as you have, Heidt's ProG, etc.
I am running an LS3/4L60E, so we should be pretty much the same wt.
Like many, I am just a rookie at this too, so can offer no advice worth a crap.
My front crossmember of the subframe is about 5-1/4" off the ground. The bottom of the CA at the sub frame is about 5-1/2" off the ground and at the wheel, its 5-1/4" off the ground.
The bottom of the shock is about 4-1/4"
My front tires are 225/40/18s, and if your running anything with less profile, your going to less clearance. My buddy riding with xxx/25/19s has a very stiff ride and is in the midst of changing tires and wheels. (He is on an Alston Subframe.)
I am still getting some setting but the ride is good, no complaints.

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Stinger, Thanks a bunch for the info and the reply! My front x member is 5 1/8" off the ground and the ca arms are 5 1/4" at the frame and 4 7/8" at the ball joint. My tires are 255/40/17 which are 25" tall. I can live with the ground clearance I have now but the instructions from Heidts wanted the arms level at ride height. Keep in mind that these figures are with 1 1/4" spacers between the lower shock mount and the lower control arm and no preload on the springs. Set up like this the 10/dp500 springs Heidts recommended have about 55 percent of travel left for compression. This seems to me to indicated the springs are close to optimal. I believe what I've done by spacing the shocks an 1 1/4 is, as a practical matter, to make 13 1/4 inch shocks out of the original 12 inch shocks. I don't know what else to do besides buy new, 13 inch shocks . The optimal answer, I think, is new spindles with less than the 2" drop that these spindles have.Heists says these are the only ones available. I'm a little frustrated and feel like I'm kind of cornered. Thanks again, Bill