Got tired of looking at the nose up stance on my small block 73 coupe with manual transmission and no a/c. I suspected that the weight reduction from swapping out cast iron intake, heads, water pump and copper/brass radiator for aluminum units was the likely cause. The front ride height measured from the top of the wheel arch is 29”. I’d prefer that it be 27” so I figured I’d just pull the front springs out and cut off one full coil, simple, right?
I just pulled them and was happy to see that both still had their green tape tags on them (331316 MA) but I noticed that one spring was shorter than the other. The shorter one off the passenger side had already been cut (fresh shiny surface). It looks like one full coil was removed based on the clocking of the ends relative to each other. The shortened one measures 15 3/8” and the other one is 16 1/4”. My research tells me that 331316 is the correct spring for my car and its free length should measure 15 7/8”.
I have no reason to believe that these are not the original springs and the front suspension retains all the original riveted ball joints which I’m going to R&R while it’s apart.
The car sat level side to side with 29” at the wheel arches despite having one coil off the passenger side. Why would someone in the past have done this? Should I just cut one coil off both springs as planned to achieve the 2” reduction in ride height and forget about what I saw?
All responses are welcome and appreciated.

Shortened spring

Shiny cut end

Uncut spring 3/8” longer than expected.

Uncut spring with 52 year old patina

Original PN tape tags



Thanks, Ken

 

Hello Ken,
I agree that the ride height dimension of about 27" is good if the wheel/tire height is near stock.
Have you noticed that original front springs have some more CLOSELY wound coils at one end.
Which end of the spring you found had been cut?
Regards.....

 

Hi Allen,
yes I noticed that the top end coils are closer together. That is the end that had a coil removed and it’s the end that I anticipated cutting to achieve the desired 2” drop. I’m concerned that cutting an additional full coil off might yield more than 2” on the passenger side.

Thx for the reply, I’m interested in what else you may have to tell me about this

 

Hello,
I think I'd begin by looking at the spring load rates and spring part numbers for the springs you have.
You also need to understand the affect the coil spacing has on ride height (at rest).
In my 71 AIM that info is UPC 0, Sheets A-11 and A-12.
Likely there the same or nearly the same in your 73 AIM.
Do you have those sheets?
Regards.....

 

Yes I have the 73 AIM. I know that the replacement springs sold by CC/Paragon claim to be rated at 450lbs like Chevy originals. I’ll see what I can learn from the manual.
Let me know if you have any further thoughts on what might be causing the disparity and subsequent “fix”by the previous owner. I’m afraid the frame may have been tweaked in the past and not straightened or not correctly. I’m pretty good at catching the telltale signs of collision damage on these cars and nothing is jumping out at me. Ive owned it for 6 years and drive it several times each week on all manner of roads. It drives nice tracks straight and corners well without any issues. I purchased it because it gave all indications of being a cream puff L48 that hadn’t been beat on but a lot can happen in 50 years and 4-5 owners.

 

Update: put the front suspension back together after only cutting one full coil off the driver side spring. That now matches the passenger side spring that had been cut previously by a prior owner. Didn’t know what to expect for a new ride height based on the combination of factors I’ve described inmy initial post. After taking a couple laps around my neighborhood to let the new parts settle in I took a measurement. The front fenders now sit at 28 1/2” measured at 12 o’clock of the wheel arches. That’s only a 1/2” drop after removing a full coil off the stock springs. Today Im planning to tighten the end bolts on the upper and lower control arms with the full vehicle weight on them and then take it out for 20-30 miles of curves, cornering and start stops. Hopefully it drops a little more.
I also rebuilt my weeping front calipers, converting to o-rings, while I had things torn apart and replaced all the original ball joints and upper control arm bushings with new Moog units. At 71 years of age, Im happy to be healthy enough to accomplish this work at home by myself for approximately $300 in parts materials and a couple new tools. 👍🏻 My Tylenol expense is not included in the aforementioned costs 🤨

 

Hello,
At 71 I'll bet you have 10 more years left to work on your car!!!!!
Regards....

 

Thanks Allen, I’ll keep that in mind when I seriously start to plan the rebuild of my 4-speed.

 

just saw this post. i’ve tried CC 450lb gt springs and wasn’t happy the the ride and height so i went with ridetec dual rate spring. had to cut half coil off to index them and final ride height was 27-1/8”. looked great and drive nice

i ended up going with coil overs last year and still have both sets of springs if you want them
or anyone else wants them.


top pic is with CC450lb springs no A/C aluminum heads

ridetec springs no a/c aluminum heads.

both sets only have about 5k mi on them

 

Thanks for the input blueL48, where are you located?

 

Hey Ken.
One way to level out the rear end stance side to side is to cut the opposing front spring.
So if the left rear is a little low you can cut a little off the front right coil which will lift the left rear so the car is level side to side.
Bubba engineering.
After you drive it for a few miles everything should settle, then check it again.
It looks like you’ve been offered a nice set of springs, I would definitely take bluel48 up on his offer!

 

im in ct

 

sent you a PM

 

Just following this out of curiosity, and I think I have something to contribute.

No one has mentioned that while cutting springs will lower the ride height, the spring rate will rise significantly. To lower the ride height one inch for example, you'd have to cut that inch off its INSTALLED height and the rate will skyrocket. Our cars ride pretty stiffly anyway, and I love that about them, but it should be considered.

Also, I wonder if anti-sway has been at least partially covering for the uneven springs, keeping the car level.

Just some thoughts from a newbie....