The urethane cushions look to be taking up allot of your bolt length and causing the rear to be higher than normal along with the nut being ran all the way up.

You have a few options, change the cushions to rubber and this should drop the rear some but not sure how much or you could trim the urethane cushions down some and see how much drop you can gain, get longer spring bolts.

Look at the cushions in the pics Alan posted, they are not near as thick as the ones on your car.

Neal

 

👍👍 thanks Neal!

 

https://m.ebay.com/itm/1963-1982-Cor...d354d03:g:tawA at 8-3/4, these are the longest I have found.

 

I know on my spring bolts, I have 'nylock' nuts so you don't need cotter pins.

 

I still think drilling the bolts and using a cotter pin is a good idea even with nylocks. Cheap, quick and easy insurance.

 

Hi,
I believe because of the geometry used in the rear suspension design lengthening the spring to t-arm bolt DECREASES the ride height dimension by about HALF the INCREASE in bolt LENGTH.
I.E. A 2" LONGER bolt decreases the ride height about 1".

This may be why you see folks trying to use 10" long bolts to get the decrease they need.

Regards,
Alan

 

I actually like the way that looks, 1980?

 

To me it looks like a couple problems-the wrong spring liners and Urethane bolt bushings as mentioned previously. In addition are those KYB white high pressure gas shocks-they tend to raise the ride height on cars.

Might be time for a complete redo-get the composite spring people always rave about, lose the KYB high pressure shocks for Bilsteins or Koni's

 

I dunno, Alan. I think the length of the bolt is how far below the top of trailing arm the spring end is hung. Unless the spring arches higher once set lower, it should be linear change in ride height.

 

It isn't. Going from original bolts to 8" got me about 3/4", everything else being the same.

 

Thats what I was thinking. Get rubber cushions and 8 inch bolts. I'd just replace the spring with a composite spring and be done with it.
So new cushions, bolts and spring should get you lowered.
What year is your car BTW. I see hints of 1980 but you never mentioned it. Not sure what year but the composite spring came out on the late C3's.

John

 

I'm gonna say that those urethane cushions are the issue. Look at how little they are compressed with weight on them compared to Allan's photos with no weight.

 

I would run that nut out to the pin like they said , but it looks like your going to need a longer bolt. I had the 235/55/15 tires which were a total height of 26 inches. They looked tiny.The original tire size was 27 total inches. The 255/60/15 are a total of 27 inches so its the correct size but we are used to seeing a bigger wheel. The 17s I have are a total of 27 inches. 1 inch total is a big deal visually but you just have more rubber.


235/60/15 = 26 inch

235/55/17 = 27



longer bolt clearance

I have the nut run up 1 inch to levle the car fron to back. I now have springs to lower the front and that little bit of thread will bring the car back down to the tire, Amazing how much the springs will move the fender up and down. But you need a lot of thread

 

Nice ride!! Thanks for the advice... ordering a kit today! 👊

 

Hey kids!! I'm still learning how to navigate this site, but wanted to throw out a HUGE THANK YOU to everyone for their input and advice about my suspension. I ordered the 8" bolts from eBay as one member suggested and he even shared the link with me (I apologize for not knowing your handle/name off the top of my head) but thank you, thank you... Here's a pic of before and after. Super stoked!! You guys are awesome!

 

That’s a terrible set up. If you get a flat rear tire, that bolt is going to contact the ground and possibly damage the spring and rear suspension. You shouldn’t have any part of your suspension lower than the lowest point of your rim.

 

That is something that has been brought up numerous times on the forum, but so many people don't see how unsafe it truly is.
Can you imagine getting a flat at 70 mph on the highway and have parts of the rear end flying out from the bottom of your car.
If you use longer spring bolts to lower your car, insure that no part of the suspension or bolts are lower than the bottom lip of the wheels.

 

congrats it looks good,

Neal

 

Here are photos of my 73 Convertible with a 78-79 rear end cover (2 1/2" wide spring). Using 8" bolts and had my 9 leaf spring re-arched by Eaton Detroit. Rear fender lip is now 27 1/2" with 255/50/15 tires. We took about 2" of arch out of the spring that I had purchased new a long time ago from a vendor. Before the change rear was 29 1/4". Rear spring is now almost flat and the half shafts are almost horizontal. Front now has Global West Tubular A Arms and Viking Coilovers. Fenders are 26 1/2" I am in process of aligning it now, but all put on hold due to recent eye surgery lifting restrictions. Really anxious to drive it again to see how it handles.

 

are not you supposed to remove the two clamps on the spring leaves ? they are there to just hold it together during shipping.

BUT the stance sure looks great