Heavy Duty Coil Springs

[Vintage_barry]

I’m due for a new set of coil springs and my question is do I go for the “variable” heavy duty springs (more in line with factory GS) or the “constant” average springs?  I’m looking for comfort of course but how much stiffer are the heavy duty?

Moog 5030 in the front (w/ac)-purchased.        Moog 5245 “constant” rear or Moog CC503 “variable” heavy duty are the two choices in question. Does anyone have experience with the 2 ride options and advice?  Thanks, Barry 

[RivNut]

I have experience in replacing factory fitted air shocks using cargo springs (variable rate)and regular shock but never substituting cargo springs for regular springs. Unless you're going to add a lot of weight to the rear, trailer or a trunk full of ice and beer, there's probably no need for the variable rate springs.  The H2 (not Gran Sport) handling package springs are stiffer and change the stance of your car.  Call the folks at Coil Spring Specialties and discuss you questions.

[Vintage_barry]

Thanks Ed. I just contacted Moog and they no longer produce the CC503. I think I’ll just settle for the standard “Constant Rate” spring but I’ll give Coil Spring Specialties a call. I was surprised that Moog said that more people purchased the variable rate spring but they decided to stop production. 

[Kevrev]

Hi Guys, My 65 sits lower on the drivers side. Do I get them all re set, or I have heard you can get spacers for them. Is this correct

[Vintage_barry]

Your springs might be ready for replacement also.  There are spacers that will lift that spring by keeping that coil from compressing but then your defeating the job of the coil spring.  My passenger side is slightly lower and the ride is to hard even with new shocks.  New coil springs should be the cure.  I talked to a technician from Moog and JEGS about springs and they both convinced me the constant rate springs were just fine unless I was going to drive the car like I had stolen it in the curves.  By the way, Amazon had the best prices with the free shipping.

[RockinRiviDad]

new springs may not solve an uneven ride issue. 
 

There are also spacers that sit under your springs. Maybe called “spring perches”??
 

my car had 1/2” spacers/perches under the driver side rear spring when I took the old springs out. These spacers/perches do not look DIY. They  are round, made of metal & have a large grove carved In them where the end of the coil rests in.

 

I replaced my old springs with brand new (1” lower than standard H2 specs, 2” lower total), 400 pound spring rate H2 springs from CSS & my car still sat uneven. It was lower on the driver side. So I shoved that 1/2” spacer/perch back in & it’s still uneven. My thought was to find a slightly larger spacer/perch to solve my problem. But that’s as far as I’ve gotten 

 

[telriv]

Did you ever think to check the installation of the front springs???  IF the right front is not installed correctly it would make the car seem like the problem was in the rear & not the front.

 

Tom T.

[RockinRiviDad]

I installed new springs in the front also. 
 

good call on checking my installation. Hopefully that is the issue fingers crossed 🤞🏼 

[telriv]

The bottom of the coil end needs to be close to the hole in the bottom of the lower control arm.  The top of the spring fits into a pocket, some have a spacer from the factory or maybe the top is not properly into place & cocked to one side.  Problem is you won't really be able to tell without removing the spring or at LEAST the shock absorber, BUT I still think the spring has to come out.

 

Tom T.

[chuckfmtexas]

I just replaced all four coil springs on my 69 Riviera this past summer.  You can search for my posts here to see the discussion.  The car was restored 8 years ago and then sat in a storage building.  It really was not driven at all.  The coil springs were replaced at that time 8 years ago and I have the EATON receipt for the springs with model numbers from the supplier.  When I bought the car in May out of storage It sat too high both front and rear.  I bought new front and rear 'stock' coil springs from Coil Spring Specialties(CSS).  The car also had 2.5" spacers at the rear springs that had been added to the car at some time to boost the height, perhaps when the original springs sagged over time.  I removed the spacers and the with the new CSS springs the car dropped in the rear to the factory specified height.  The front with new springs was still 1.5" too high above factory dimensions.  I contacted CSS and they offered to make a set of front springs that would sit the car 1.5" lower than stock so that is what I did.  We installed them and the car sits at factory height at all four wheel openings.  I can't explain the front sitting at stock height with lower springs but it does.

 

Before Spring replacement May 2020  2" too high front and rear                                                                                                                           After Spring replacement front and rear August 2020 Factory height

.  

 

Hope that helps

Chuck

Edited October 22, 2020 by chuckfmtexas (see edit history)