[crm318]

I good friend of mine owns an immaculate 1971 455 H.O. 4 speed GTO and he is in need of a set of rear springs. The exhaust catches on the smallest of bumps. Does anyone have any suggestions on who makes a good spring for an A body convertible?

[Squidward]

Hmmm... no roof but heavier frame.... I wonder how it plays out in the weight department compared to a coupe.

I know what I got for my 72 Lemans hardtop, and I was pleased with ride height and quality. Moog 5413. Close to stock specs, maybe a tiny touch stiffer, and a tiny touch bit of lift (<1") compared to stock. But that might be because the old ones were such POS's...

[crm318]

Thanks Squid, I'll give t hem a look!

['ol Pinion head]

-What size tires on the 15x7 HC's?
-Your friend, does he realize 15x7's with G60-15's were not avail on a convertible? just on 2 door hardtops due the design of the convert wheel house.

Taller rear springs will give more height.
-Does the GTO convert have the factory firm ride suspension option? If it did & the rear springs are new correct replacements the rear will set higher than standard content '71 GTO springs.

Just throwing out several factors, had a much longer response typed. the system logged me out, & I lost it. Feel free & get some feedback, & will ck back in.

[crm318]

He has 255/60/15s. Not sure of the factory suspension options.

[Scarebird]

I ran 71 442 convertible spec springs in mine; Olds put more work into the suspension than Pontiac did IMHO.

[skullbucket]

You could add a set of these Ebay gold 1 inch or 2 inch spacers under your springs, mine works great.

[melwff]

Eaton makes standard height and a number of optional heights

https://eatondetroitspring.com/db/es-partsinquiry2.php?

['ol Pinion head]

Originally Posted by crm318

He has 255/60/15s. Not sure of the factory suspension options.

Might have your friend ck his PHS (invoice copy) & see if the car has Y96 suspension pkg. If this '71 has been restored, the rear springs may easily have been swapped as well. Not enough selection in Moog springs for many years, thus I don't use them. G60 x15's & H69x 15's (255/60R15's) need the stiffer Y96 rear springs to get the rear of the car up. Trunk load of extra weight, may even need custom rear springs. Coil Spring Specialies or Eaton are the choucrs, I've always used the former, with very good results.

[The Champ]

Originally Posted by 'ol Pinion head

G60 x15's & H69x 15's (255/60R15's) need the stiffer Y96 rear springs to get the rear of the car up

The factory G60x15 (26.4") is a lot shorter than a 255/60/15 (27.1")). The 255/60 is the H60 (27.1") equivalent.