Rear Springs
 

I'm sure this has been asked and answered but I wasn't up for the search. What rear springs are best to use on a 68 GTO to lift the rear a bit. Not high, just high enough so it doesn't look low in the rear. I'll buy the springs in the PY catalogue if they work but they appear as if they are just standard replacements. At least I'm putting it back together......feelin' good

I don't really know what would work but I think the convertible springs lift the coupes up? I'm looking in the catalog and it says the 64-66 convertible springs will sit up higher and give a little firmer ride. I'd assume the same for 68-up.

There are cargo springs made for a wagon which would give it some lift.

Webfoot....more info....? Do I just try to source rear spring for a station wagon (Lemans) or something similar (A Body).....you wouldn't happen to know a part number I can run down or a source....thanks man....

Did some research and the moog PN is cc501, I would think the moog would be available just about anywhere.

That's the number I was told from PY as well. The springs I got from my store are CC501s, but are variable rate. The ones I pulled out originally are not. So hopefully my car sits fine.

Variable rate doesn't affect the ride height, it changes the ride quality.

I'm pretty sure those are the ones I used on my vert and it gave just a little rise in the rear.

The list of applications for that part number (in Summit) doesn't include 68 GTO, but I'll take your advice and order....seems like it's been researched and verified....thanks men....'preciate it

If it lists it for any 68-72 A-body, it will work. Probably doesn't list it for a 68 GTO because it isn't specifically made for that model.

Air bags are nice also.

Years ago when I replaced my rear springs , went to junk yard and they sold me a set of used rear 1978 "G" body malibu station wagon springs. Work great for my conv. You can put 500-1000 lbs in the back without it bottoming out.

I've got an older TRW coil book from my parts days in the 80's

68 GTO stock replacement rear springs are CC509. Wagon springs are CC507. CC501 shows up in 1970. They all will fit in the car. Here's a comparison of the specs:

CC501 ride height: 8", free height: 12.83", load: 750#, spring rate: 155#/in
CC507 ride height: 10", free height: 15", load: 850#, spring rate: 170#/in
CC509 ride height: 8", free height: 13.23", load: 810#, spring rate: 155#/in


Therefore, 501's aren't any taller than the stock 509 stance. the free height on the cargo coils means their shorter than the stock linear rate springs when you stand them side by side, but once the weight of the car is down on top of them, they should sit at the same height because they're stiffer. This can cause problems if the shocks have too much travel because I've had springs shift off the mounts when the ass end is unweighted enough (like flying over a raised railroad crossing like them Duke boys!)

Anyways, the wagon springs will suck. They'll jack the ass up two inches and it'll ride like a truck with that stiffer spring rate so even though it doesn't seem like much with only going two inches, I don't think you'll be happy with the ride.

Going through the ratings matching the diameters and end point styles I think a good candidate for a slight lift would be a CS5413 ride height: 8.5", free height: 12.93", load 740#, spring rate 167 #/in. I'm almost positive that's the spring I ran in my 69 vert. Napa still carried them 4 years ago when I put the car together, not sure if they're still available. it's got the slight rake I was looking for.

I wish I would have known that when I bought mine. Oh well, the 501s I would think would still do good. I had to order them through my store, now I have a set still in stock.

That's why I went to used station wagon springs. There are all ready broken in. Not as stiff as new ones.

The original back springs from the factory were too weak for that car, thus the factory rake of the back end sitting down after a few years. My original springs were so weak that if one person sat in the back seat, it would bottom out.

I still have original front springs. As you can see from the rake on my car it sits up higher in the front but that may be due to the fiberglass hood and front bumper.

Plus two junk yard springs are cheap. I payed like $20.00 for the pair.

Turned out to be a good question and GREAT info....thankyou....got a NAPA right around the corner....

I have the 501s and for me she sits a little high. The tires have a 26" dia and perhaps 27s would fill the rear wheelwell up a bit more.

Moog has a 5413 with the specs below....got em from Jegs....thanks for the info.

My 68 Goes through rear springs faster than Tires or engines. They too soon loose ride height.

I was thinking about heating mine up a little with a torch to get them to settle just a little. I know that this is not the ideal solution.