I recently(two months ago) had a complete front end rebuild done on my 1980. When I got the car back it sat like a four wheel drive.
The guy who did the work said the car needed to settle but guess what Nada. I am going to have him check and see if the springs are in upside down or not seated. Can anyone tell me the appx height the front end should sit so I have something to go by.

Kona

 

After the frame off on my '70, I too was told by others that it would "settle." Its still sitting at 29.5" up front, and 30" in the rear (to the top of the wheel opening). Yours is probably around the same. To drop it down, you neet to either cut your front springs, or from what I hear, the 550# springs work well. In the back, you need to replace your 8" spring bolts with 10 inchers. I plan on doing the same, just havnt gotten around to it. Take a look at the picture in my gallery, I hate the 4X4 look.

Joe

 

Joe thanks for the info. My car sat really really nice before the rebuild I'm hoping the springs just in wrong.

Kona

 

Be careful - using bolts longer than 8" can be a serious safety hazard.

 

I just replaced my 6" bolts with 8" it's almost dragging the ground , I don't know why you would need any more than 8's

 

I wonder if we have gotten used to the ride height of our cars with old, worn suspension parts. Now that we put new parts and springs in, the ride height of 28 inches seems too much.

I am putting a new 9 leaf steel spring and am waiting for my new 8 inch bolt kit to arrive. When I measured the car before I started the ride height was 26.5 inches. I see from the ride height table that somewhere around 28 inches would be normal.

My ride height may have been lowered due to the bad leaf spring. Both sides of the top spring were broken where the leaf spring bolts to the differential.

kdf

 

Nah, lower is better. I'm sitting at 25.5 in front and it looks real nice.

 

Use these ride height specifications to determine the current height vs. the desired height. You will likely be satisfied with the lower end of the factory specs.

 

You shouldn't NEED any more than 8" bolts but unfortunately not all aftermarket springs are made with the correct load height (arch of installed spring) so bolts greater than 8" are sometimes needed.
The load height of my spring is too high for my car. To compensate for this I had to install ridiculously long end bolts to bring the ride height down to factory specs (or add a few hundred pounds of weight over the rear suspension)
This corrected the ride height issue yet created another problem. The ends of the springs were lower than my O.E. 15" wheels.
http://temp.corvetteforum.net/c3/miker//ripped_06.jpg

Eventually I managed to cut a tire on the end of the extended spring bolts.
http://temp.corvetteforum.net/c3/miker//ripped_01b.jpg
http://temp.corvetteforum.net/c3/miker//ripped_02.jpg
http://temp.corvetteforum.net/c3/miker//ripped_04.jpg
This occurred while making a right turn into a parking lot that had a sharp rise for drainage. The combination of turning (a bit too fast) while hitting the rise made the sidewall contact the bolt. I have since cut the bolts off just below the nut. I didn't cut them right away because I wanted to be sure I was satisfied with the ride height. (...replacing this tire effectively added another $100 to the spring and 10" bolt purchase )

I have my ride height adjusted within the specifications found in my 1980 Corvette Shop Manual. http://temp.corvetteforum.net/c3/miker//ride_height.jpg
My ride height in the rear is currently:
104% of MIN, 97% of TARGET, and 90% of MAX.
My ride height in the rear prior to installing longer bolts was:
115% of MIN, 106% of TARGET, and 100% of MAX.
GM allowed a surprisingly large span (~2.3") between MIN and MAX. To me it's the difference between a 4x4 look and that "just right stance".
Yet another problem I had while riding at 100% of MAX ride height spec was the poor geometry of my sway bar end links. You can see the difference in this picture:


post edited to correct photo links

 

Miker thanks for the info!

Kona

 

sounds nice..Pics?

 

Wow Mike, I'm surprised you didn't rip out the rear suspension! A lot of people have switched to 10" bolts - they should see your pics. You should never have the bolt hanging below the bottom of the rim.

With regard to the front - thiscould be a stupid suggestion but if you tighten the control arm bolts with the car on the lift it will sit too high - you have to tighten them with the car on the ground - check it by loosening all four bolts (on top) and see if the car drops down. Then tighten. Otherwise, the springs might not be seated properly.

I've also heard that some people have had to have their new springs re-arched. If you installed a composite spring in the rear this is another problem - most of them sit too high and there ain't much you can do about it (don't ask how I know...) - check my ride height in the pic below -

 

The sound of that bolt dragging the ground was pretty wicked! Since then, I've cut the bolt and installed 17" wheels. When I have another flat tire, I dont think that the bolt will touch ground before the wheel any more.


Here are some additional pictures of the punctured tire. Most of the tire damage seen in these pictures was done after the tire went flat, before I stopped the car. It's hard to tell where the first puncture occurred.
http://temp.corvetteforum.net/c3/mik...040111_01a.jpg
http://temp.corvetteforum.net/c3/mik...040111_02a.jpg
http://temp.corvetteforum.net/c3/mik...040111_03a.jpg
http://temp.corvetteforum.net/c3/mik...040111_04a.jpg

 

Your '64 has an awesome stance.

 

I also noticed that the difference between worn out end bolt bushings and brand new ones makes 1/2 to 3/4 inch. So If you replace the worn out pushings to new and do nothing else your car will raise close to 3/4"!

 

Mike it also looks like the spring bolts that you replaced were only 7 1/4 inches long too is that correct? I'm riding a little high in the back on my 69 and I measured the spring bolts and they are shorter than 8 inches too. I'm hoping that some spring bolts that are a hair longer than the ones I have now will drop my rear ride hieght and still be safe with my 15 inch wheels.

 

Yes, the old spring bolts were 7-1/4".
I just came in from measuring the distance between the bolt head and the nut on my 10" bolts and I came up with exactly 8". The nut is 5/8" thick so 8-5/8" would have been the absolute minimum bolt length to get my ride height to where it is now (with the spring I am currently using.) I have cut the excess threads off of the 10" bolts.
Different springs would likely require different length bolts to achieve the desired ride height.

 

I just took this picture. It shows the difference in spring/bolt clearance between the 255/50/17, 17"x8" w/4" B.S. and the 255/60/15, 15"x8" w/4" B.S.


In this picture, my car is wearing both the 15" and 17". The 15" tires are on just to hold the car up until I can get the valve stems replaced on my new 17" wheels. I had a flat on the front left due to a valve stem that was damaged during installation. I then discovered that the valve stem on the right rear was also damaged and leaking.