1985 442 lowering rear height

[pontiacgp]

On an 85-87 442, I'd just adjust the air pressure in the shocks to get the right height.... 🙂

 

[pontiacgp]

here's my covid painted GP with the 5409 springs. I would like to get the GP a little lower in the rear but I like the spring rate of the 5409 over the 5413. The 5413 didn't drop the GP as much as the 5409 but I never left the 5413 in the GP long enough for the spring to settle. One other detail is I have an 8.2" rear end so the axle tubes are larger then the axles tubs on a 7.5" so that affects the height. I could put the 5659 springs back in which I have cut to lower the GP but those spring have a 5" diameter which means the airbags I would use to support the rear if the GP is loaded down do not fit.

 

[64nailhead]

here's my covid painted GP with the 5409 springs. I would like to get the GP a little lower in the rear but I like the spring rate of the 5409 over the 5413. The 5413 didn't drop the GP as much as the 5409 but I never left the 5413 in the GP long enough for the spring to settle. One other detail is I have an 8.2" rear end so the axle tubes are larger then the axles tubs on a 7.5" so that affects the height. I could put the 5659 springs back in which I have cut to lower the GP but those spring have a 5" diameter which means the airbags I would use to support the rear if the GP is loaded down do not fit.

View attachment 160245

Why did you like the spring rate better? Stiffer, softer, or what?

Perhaps some photos of both springs loaded and unloaded - any 300-400lb fat guys that can sit in the trunk on command?

 

[86CUT]

A friend gave me some stock springs from a gbody wagon and DAMN it sits way to high going to get a different spring as well cause its just way too high.
He changed to a differnt moog spring and got another 2 inch drop out of them compared to the wagon springs.

 

[403Olds]

here's my covid painted GP with the 5409 springs. I would like to get the GP a little lower in the rear but I like the spring rate of the 5409 over the 5413. The 5413 didn't drop the GP as much as the 5409 but I never left the 5413 in the GP long enough for the spring to settle. One other detail is I have an 8.2" rear end so the axle tubes are larger then the axles tubs on a 7.5" so that affects the height. I could put the 5659 springs back in which I have cut to lower the GP but those spring have a 5" diameter which means the airbags I would use to support the rear if the GP is loaded down do not fit.

View attachment 160245

How much more did the 5409 drop the rear over the 5413?

 

[Macguyver]

MOOG 5401

 

[64nailhead]

How much more did the 5409 drop the rear over the 5413?

I just installed a set of 5409 and it dropped the rear about 1.5". I had an antique set of springs in it, but it got raised when I put the Expoloder rear in it so I can't really say how much it changed from the original rear.

MOOG 5401

Is this lower than the 5409? How's the spring ratecompared to the 5409?

 

[Macguyver]

I just installed a set of 5409 and it dropped the rear about 1.5". I had an antique set of springs in it, but it got raised when I put the Expoloder rear in it so I can't really say how much it changed from the original rear.


Is this lower than the 5409? How's the spring ratecompared to the 5409?

Yes, lower than the 5409.

moog-5409	Pigtail	Pigtail	13.44​	7.5​	5.52​	0.55​	143​	847​	Constant Rate
moog-5401	Pigtail	Pigtail	13.15​	7.5​	5.58​	0.53​	129​	727​	Constant Rate

 

[motorheadmike]

I used Moog 5659s with a coil cut out in my old Buick:

Bar Diameter - Inches	0.50
End Type 1	Square
End Type 2	Pigtail
Free Height - Inches	13.68
ID - Inches	4.30
Installation Height - Inches	10.00
Load - lbs	576.00
Spring Rate - lbs per inch	162.00
Spring Type	Constant Rate

With a full coil cut out the rate jumps north of 180lb/in if I recall correctly.

 

[81cutlass]

Bah so many options.