C1 New Springs - Sag height question

[Joe P.]

just finished the total rebuild of the front end. Many thanks again to Tom Parson and Aaron O'Brien's posts and replies to my many emails and conversations.

I finally got it all back together and been driving it, regreased it and rechecked the ride height as indicated in the ST-12, and noticed some sagging. i ordered the deluxe kit from CC with new shocks, new springs, new everything possible. <br />

i remeasured the ride height and was surprised the seems to be some sagging in the first 200 miles. The spec is 11 +/- 1/2”. i remeasured and now have 10” on the passenger side and 10 1/4”on the driver side.<

Is this normal ? I read in the ST-12 that shims may be need at the top of the spring.. Is it a direct correlation in that i should add at a 1” space to get back into the specification?

Any recommendations on where to purchase these spacers?
Appreciate your input on this.. thanks, Joe

[Gary C.]

Re: C1 New Springs - Sag height question

Joe,

Body ride height measurements. Hope this helps you.

Gary
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[Joe P.]

Re: C1 New Springs - Sag height question

Thanks I will take some of these measurements and do a comparison and report back.

[Joseph L.]

Re: C1 New Springs - Sag height question

Those points of measurement are the easiest to do. The +/- 1" tolerance also needs to be considered. If in tolerance, and high in the front and low in the back; it will be visually apparent. That condition will show as a droopy rear.

[Terry D.]

Re: C1 New Springs - Sag height question

Did you measure right after completion? You don't say what size tires you are running.

[Joe P.]

[Gary C.]

Re: C1 New Springs - Sag height question

Joe,

Curious about the height differences. Did you measure before replacing for a base line?

Were the front springs installed correctly? IIRC there's a ridge on the lower A Arm that blocks the spring end from turning.

Gary
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[Joe P.]

Re: C1 New Springs - Sag height question

Joe,

Curious about the height differences. Did you measure before replacing for a base line?

Were the front springs installed correctly? IIRC there's a ridge on the lower A Arm that blocks the spring end from turning.

Gary
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Gary i didn't measure a base line before the dissasembly.

when i installed the spring i installed them to the same location that i took them off. just on the edge of the drain hole. i didnt notice any ridge. IMG_7846.jpg

[Gary C.]

Re: C1 New Springs - Sag height question

Joe,

You did good reinstalling the spring. Ridge bump visible in your photo.

Gary
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[Joe P.]

Re: C1 New Springs - Sag height question

Joe,

Body ride height measurements. Hope this helps you.

Gary
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Gary I measured 27 1/2' from the ground to the center of the headlight, on the rear fender well I measure 29 3/4"

[Gary C.]

Re: C1 New Springs - Sag height question

Joe,

Please post a level side view photo.

Gary
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[Stephen L.]

Re: C1 New Springs - Sag height question

Why not use the concept for ride height as used on C2's.

Front: 1) Measure from the bottom surface of the spindle to the ground
2) Measure from the bottom of the lower "A" frame mounting bolt to ground
3) Subtract these dimensions from each other.
This procedure will eliminate discrepancies in tire height, inflation, body condition, etc.

Rear: 1) Measure distance vertically between the frame bottom surface and the top surface of the rear end housing.
Again, this eliminates discrepancies in tire size etc.

You will need to survey C1 owners to obtain an average of what those dimensions should be....... unless this information exists in GM documentation.

This can eliminate differences due to body mount condition, poor body repairs etc.

Hope this might help the C1 owners

[Gary C.]

Re: C1 New Springs - Sag height question

Stephen,

Great idea. Unfortunately, there are not any C1 factory dimensions like they are for C2's.

Only ride height to ground are from AMA specs, previously attached with mark ups and the '57 AIM - see attachment.

Gary
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[Stephen L.]

Re: C1 New Springs - Sag height question

Gary,
I realize that there are no specs like there are for C2's. I did suggest that a SURVEY of C1 owners might yield a dimension average that could be refered to..........using the C2 technique.
Steve

[Gary C.]

Re: C1 New Springs - Sag height question

Stephen,

Sorry, didn't explain very well. C1's have a tendency to squat, meaning the rear springs sag. Which means getting comparative measurements, won't give you good data. That's one of the reasons I asked Joe to post a level side photo.

Data points from my previous posts:
- post #2 - 13.2 inches from ground to center of rear axle
- post #14 - 11 inches frame to ground

Gary
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p.s. measurements from ground depend on the type of tires that are on the car - factory to ground measurements are for OEM tire size