G body springs

[TOURING-TURBO-T]

Looking for some input on springs for my 87 regal. I dont think the eibachs will be enough drop to close the fender gap. I have used the moog 5413's but I dont like that they fall out if you dont jack it up on the diff. Any ideas will be appreciated. Tires are 245-40-18 and 275-35-18.

[canadiantbone]

I used hose clamps to hold my 5413 to the rear axle . quick & simple fix .

[Norm Peterson]

The hose clamp "solution" ↑ by itself makes me uneasy. Make that a lot uneasy. You want positive lateral location for the top of the spring right there at the top of the spring in addition to somehow constraining the bottom pigtail against popping out of the lower seat.

I'd have much greater confidence in something like short lengths of pipe or possibly exhaust tubing welded to the upper spring seats that fit inside the spring pigtails to keep the 5413's "captive" over the full length of shock extension/suspension droop, though you'd still need to do something with the bottom pigtail to keep it captive under dynamic conditions.

Shimming the upper seat (this being in addition to the tubing mod) such that the spring is still under slight compression with the shock at full extension is another approach, and would avoid having to "hose-clamp" the bottom of the spring or add tubing to the lower seat. More or less, that's how I dealt with the installation of 5413's on my avatar car. I suppose that I could have dropped the rear ride height a little had I been willing to make sacrifices in several areas of function for the change in "stance", but - mostly for the benefit of a couple of newer members here - I'm oriented much more toward what my cars are like to drive rather than anything particularly noticeable about their appearance.


There might be another solution that would work with upper spring seat tubing mods, but if you're at that point it might be better to just go with a set of circle track springs and ride height adjusters and be done with it.


Norm

[Hotchkis]

Our G-Body package works REALLY well and our Sport Springs offer a great combo of lowered ride height and a sporty but still comfortable ride. It's funny... 25 years after the G-Body was on the market the new Camaro has the same issue, some of the other companies out there have springs that will fall out at full droop unless you tie wrap them in. On both platforms, our springs are engineered to collapse inside themselves on full compression so the stay in place at full droop but still lower ride height and improve performance.

Here's a link to a Hot Rod story about our G-Body stuff... the article is old but still a good read.

[Tony_SS]

Spend more, but they work. OPG drop springs. You can get them in 1 2 and 3" drops. I have the 3" up front and 2" rear. No issues with them falling.

[MADMIKE]

Shimming the upper seat (this being in addition to the tubing mod) such that the spring is still under slight compression with the shock at full extension is another approach, and would avoid having to "hose-clamp" the bottom of the spring or add tubing to the lower seat. More or less, that's how I dealt with the installation of 5413's on my avatar car.

Norm

Norm I'm curious what rear shocks are you using?
If Bils are they the older coarse threaded bolt or the newer thicker fine thread?

My newer Bils do not allow the 5409s to fall out, where as I thought the older units did.(old and busted vs new hawtness)

[Norm Peterson]

Don't know. I've had them since October of 2002, if that helps any.

I have 5413 rear springs that had to be shimmed a little over an inch after they settled.


Norm

[ArtosDracon]

Limiting straps would be another easy solution. I know they're not found on pro-touring cars, at all really, but they work great in the off road world and in function, they are unlikely to ever effect your suspension, if you ever got that much droop, your spring would have moved/dislodged.

[MADMIKE]

Don't know. I've had them since October of 2002, if that helps any.

Yes it does. My 'old' shocks were purchased around '05 I think, the new ones were purchased in 7/07 after the lower stud failed when switching from 5401 to 5409.

I have 5413 rear springs that had to be shimmed a little over an inch after they settled.

Norm

5413 167 lb/in 740lbs @ 8.5" FH=12.93" ('71 GTO)
5409 143 lb/in 847lbs @ 7.5" FH=13.44" ('67 GTO)

5401 129 lb/in 727lbs @ 7.5" FH=13.15" ('69 GTO)
5379 122 lb/in 760lbs @ 8.5" FH=14.75" ('78-'88 A/G)
6321 119 lb/in 689lbs @ 8.5" FH=14.29" ('83-'87 GP)

My 5409s do not fall out and they have been installed since 7/07. Could this be an alternative for you? Or do you require the higher spring rate?

FWIW I changed my rear bumper out to an AL unit, reducing weight ~25lbs. The rear doesn't try to swing you around as much(polar movement?). It is also common for the '78-'80 Cutlass to have AL inner structures as well. I do not know if that is interchangeable with the Malibu.

[ArtosDracon]

The aluminum core support is, that's the only one I know for sure interchanges.

As I recall G-body springs are 5.5" OD with dual pigtails, why don't you all just get some 5.5" circle track springs in whatever spring rates you want. 5.5x13 is relatively common and I know they have 800-1200lb springs at least, not sure about dual pigtails, but it seems like it would be pretty easy to fab up an adapter with a small piece of plate and some tubing.

Or, figure out the ID of the pigtails, and just run a smaller diameter coil-over spring. I realize they're not as stable laterally, but that's why your four link is triangulated on top.

[Norm Peterson]

Could this be an alternative for you? Or do you require the higher spring rate?

I needed the spring rate for highway "flat ride" reasons (my car is a little less front-heavy than most G-bodies), and at 65 mph the ride is almost pure 'heave' even when you are aware of suspension movement. If I go through the car again, losing some bumper mass might end up being one of the smaller changes, and I'll probably be on a still different set of springs.

I think the car might have had 5409's or something of similar rate as it was delivered (original F41, four speed manual, no A/C). I know it was higher than 120-ish.


Norm

[86Cutlass383SR]

I don't have them installed yet and I was going for a stock ride height with increased spring rate. I also wanted the option of cutting the springs if need be. I went with the Moog 5659. They are open on top and pigtail on bottom. Here's the specs according to the chart on MalibuRacing.com:

Inside dia 4.3"
spring dia .500
Load height 10.00
spring rate 162#
free height 13.55
spring force @ installed height 575#

I'm currently going to run my 5662 front springs but for a stock height but I also have alum heads, etc so I'm not sure where I'll end up. I'll tailor the ride height after I get the engine in and the springs settle.

Anybody heard from Marcus lately? I'm sure he could give some insight on this.

[MADMIKE]

I needed the spring rate for highway "flat ride" reasons (my car is a little less front-heavy than most G-bodies),

I changed out the hood and front bump to AL units as well along with replacing the WP with a GMB AL unit that saved ~ 60lbs off the nose. Up high and in front of the wheels to boot. The car is my DD, and with the exception of possibly needing to trim the front 5660s a bit, the car rides fine.

I think the car might have had 5409's or something of similar rate as it was delivered (original F41, four speed manual, no A/C). I know it was higher than 120-ish.


Norm

5409s are derived from the '67-68 A body coupes. Doubtful they ever were factory installed into a '78-'88 A/G.

F41s had the Cargo coils(variable) out back, CC627s. The later GP/MCs had their own rear coils CC651

CC627 107 lb/in 600lbs @ 10" FH=15.63" ('78-'88 A/G)
CC651 116 lb/in 405lbs @ 11" FH=14.63" ('83-'87 GP)

The CC627s I experimented with were too damn harsh. The first 1" was probably 106lbs as it was soft as ****e.
But beyond that you could fill the trunk with rocks and the rear would not sag.

FWIW Wagons used either;
5391 142 lb/in 909lbs @ 9" FH=15.40"
CC507 158 lb/in 849lbs @ 10" FH=15.38"

[Norm Peterson]

I'm only guessing 5409; the actual spring had a GM part number that I had some information for. It's been a long time, but I'm quite sure that they weren't progressive.


Norm

[liquidh8]

FWIW, I used AFCO circle track springs, one pigtail, and the height adjustment spring cups for the rear, and I used the non pigtail springs and adjustable spring cups for the front too. I like the set-up. And since I am moving the suspension over to my buick, with a lighter turbo V6 instead of the iron headed V8, I can just get another set of AFCO springs in a lower rate. more to choose from you know?

[ArtosDracon]

Look at speedway motors, they have several brands, including their own, and their prices are the best I've seen around.