Rear Springs

Hi Guys,
I'm overhauling the suspension on my 95 RMW.
Call me unenlightened, but I'm having a hard time finding out for certain what is the installed height of the rear springs.
Rock auto lists the following rear springs with corresponding installed spring heights:

Moog # / AC Delco # (application) - installed height:

5417 / 45H2044 {#88913714} (wagon) 8.5"
5245 / 45H2007 {#88913677} (sedan) 9.0"
5419 / 45H2022 {#88913692} (sedan, heavy duty) 9.0"
CC623 / 45H3012 {#88913773} (wagon, variable rate) 11.0"
CC621 / 45H3011 {#88913772} (sedan, variable rate) 12.8"

The dealer Order Guides from GM state a "checking height" of 11.9" for the sedan.

I doubt there is a 2.5" range of ride heights among wagons (or 4.3" among all B bodies)
I want the car at stock ride height. At stock ride height, what is the distance from spring seat on axle to spring seat on frame?

Thanks

do you want firmer springs ? variable rate ? check out the moog chart. They calculate installed height from free height using load and rate.

If you want a stock height wagon with a firmer spring, use CC625. CC623 lifts it.

http://www.moog-suspension-parts.com/universal_coil_springs.asp

I do want stiffer springs, but not necessarily variable rate. (I'm putting 880 lb. springs in front & I don't want the car to plow)
I'm looking at the Moog chart, no 2 springs listed for the B-body have the same "installed height".

Even when recalculated with the free heights & rates Moog quotes, loaded heights for 5417 in the B-body wagon at 980 lbs. (1/2 of approx. sprung weight of B-Body wagon) is 9.9".
Loaded heights for 5245 & 5419 in the B-body sedan 740 lbs. (1/2 of approx. sprung weight of B-Body sedan) are 11.4" & 11.7", respectively.

better put some shocks with a LOT of rebound control with those springs or you will not be happy.  Koni adjustable set on full hard or a non-b-body bilstein.  I run 710 lb springs in the caprice with Koni adjustables set to full firm and it can get super shitty on quebec roads for a DD.  I've been to NS.  You're in the same boat.

you're going to need to run a non-b-body rear spring if you want stock height, firmer, linear rate.

jasonlachapelle wrote:

better put some shocks with a LOT of rebound control with those springs or you will not be happy.  Koni adjustable set on full hard or a non-b-body bilstein.  I run 710 lb springs in the caprice with Koni adjustables set to full firm and it can get super shitty on quebec roads for a DD.  I've been to NS.  You're in the same boat.

you're going to need to run a non-b-body rear spring if you want stock height, firmer, linear rate.

Do you run the cc625 in the back?

What's its loaded height in your wagon?

yes, but on my wagon in BC.  It's 1" shorter than the CC623 I have here.  Same ride as the 623 but stock height.

I can measure the cc623 for you if you want when it stops raining. Most people use ground to wheelwell on the wagon to give an idea of the ride height.

The CC623 put my car up in the sky. As soon as I was done with towing duties, I took them out. They ride okay, but are huge. If I remember right it was like a 2" lift from stock.

I ended up getting Moog 80860 (780 lbs./in.) for the front & Moog 6101 (389 lbs./in.) for the rear.

just out of curiosity, why didn't you go with the 7268 or 80098 ? Pretty much stock ride height. Yours might sit higher than stock on a wagon.

Let us know how you like it. Get some good shocks.

11.9.6"t ote="jasonlachapelle"]just out of curiosity, why didn't you go with the 7268 or 80098 ?  Pretty much stock ride height.   Yours might sit higher than stock on a wagon.

Let us know how you like it.  Get some good shocks. [/quote]

Moog 80860 14.23" free height, 780 lbs. /in at 1840 lbs. load yields to a height of 11. 9", right about stock front height.

Moog 6101 13.12" free height, 398 lbs. /in at 980 lbs. load yields to a height of 10.6", pretty much spot on to what I measured with the rear springs on the car now.

ok. post pics and a ride report. Look forward to seeing what rear springs about twice as firm as stock will do. Once you compress that spring, it's going to rebound with a LOT of force.

My front fender arch centre is at 28" with the 7268 using a 26.7" diameter tire. My rear arch is at 21" running the CC623, using a 27" diameter tire. I'm thinking your front might be a bit high with that spring. I hope I'm wrong.

It's actually a bit raked (higher in the back). My tires are 28.7" OD.
I'm still waiting for my shocks, they're on back-order from Summit.
With the stiffer springs, Delrin control arm bushings & stock body bushings, ride wasn't much harsher than stock. I noticed a bigger change going to 40 series tires.
Car handles MUCH better now.

Ugh. Photobucket is garbage. Put your photos on imgur.com instead so they can be seen.

Big Jack, Could you make the pics a bit smaller? They really distort the thread.

Fred Kiehl wrote:

Big Jack, Could you make the pics a bit smaller? They really distort the thread.

Did what I could, now the photos are all out of proportion, but you get the idea

You should get some clean looking lugs, that would make a huge difference.

Brandt51 wrote:

You should get some clean looking lugs, that would make a huge difference.

Nothing stays clean for long when it's parked a 1/4 mile from the Atlantic ocean every night. It's pretty much an ultimatum: rusty or greasy

jasonlachapelle wrote:

ok.  post pics and a ride report.  Look forward to seeing what rear springs about twice as firm as stock will do.  Once you compress that spring, it's going to rebound with a LOT of force.

My front fender arch centre is at 28" with the 7268 using a 26.7" diameter tire.  My rear arch is at 21" running the CC623, using a 27" diameter tire.  I'm thinking your front might be a bit high with that spring.  I hope I'm wrong.

Due to delivery delays & time constraints, I upgraded suspension in 4 stages:
1. Firestone Indy 500 Firehawk 275/40-20's on 20"x 10"s all 4 corners.
2. ALL suspension pivot points replaced with delrin (spherical on trailing arms), Front & rear springs, front & rear swaybars.
3. Polyurethane body mounts.
4. Adjustable shocks.

Observations at stage:
1. Way better grip, harsher ride, but still bouncy.
2. Firmer ride, MUCH better cornering, no noticeable increase in harshness.
3. Biggest increase in harshness over potholes, ect. Somewhat regrettable. I guess chassis is stiffer.
4. With fronts set to rebound damping level of 11 of 22 & rears set to level 15/22, car rides & handles pretty good. Mitigated some of the harshness. In hindsight, I should have dyno'd the shocks. Another good thing about these shocks is that with rear axle hanging, springs can be wiggled/turned on perches but won't come out.

Let me know how you like those Indy 500s. I just ordered 255 35 20/295 30 20s.

jayoldschool wrote:

Let me know how you like those Indy 500s.  I just ordered 255 35 20/295 30 20s.

Prior to the indys, I've only had marathon trailer tires & snow tires after that, so I think the indys are awesome.

lol, yeah, they would definitely seem like upgrades.

My previous stickies have included BFG ZRs, Michelin Pilots, and Khumo MXs... I'm looking forward to giving the 500s a workout. Just installed a fresh set of Bilsteins today, and am in the middle of doing steering and ball joints.

^ On what, Mr. No B wagon?

You know this car. Old pics, I need to get some new ones when the new wheels get here.

Ah right. I had forgotten you owned that, honestly. LOL

I almost did, too... getting back to my roots.

You almost Crovo'd.

Never go full Crovo.