1" front 2"rear ?

jshot

Member
Aug 8, 2018
76
10
8
37
Ontario, Canada
I am running stock tire height and i want to get a nice level. was thinking dropping 1" front 2"rear ? ....thought? pics? i like my nice cushy ride of my stock springs. how do i keep this? do i need to combo with shocks to go with springs?

thanks
 

1986 Buick GX1

GX1 #001 [The One and Only]
Apr 24, 2015
1,259
271
83
55
Manly IA
If you know you want a 1" drop front/ 2" drop rear set up it would be best to type moog springs in the search bar. There are a lot of informative threads by Charlie f1 and jdpolzin about moog spring rates and heights.

For reference the GN/T front spring rate is 422 lbs/ in. and the rear is 118 lbs/ in.

Yes, the shocks will play a large part in ride stiffness. Monroe is soft, KYB are medium and Bilstiens are firm.
You can use your current shocks to start and go from there.
 

1986 Buick GX1

GX1 #001 [The One and Only]
Apr 24, 2015
1,259
271
83
55
Manly IA
It seems most list the 5658 fronts, 1" drop 530 lbs/ in. spring rate and the 5413 rear, 1" drop 167 lbs/ in.

These may be a bit stiff for you, however I like more of a Z28 or GTA ride and have had some ATR performance handling springs in the past. Although not listed, I think by the wire diameter the springs were in the 530 lbs/ in. front and 125 lbs/ in. range and even with bilstiens I thought the front was a little soft.

The 167 lbs/ in. rear springs may help plant the tires at the strip, but I feel they would throw off the balance of the car handling wise.
I would not be afraid of the 530 lbs/ in. front springs especially with softer shocks if you could find some rear springs in the 120 lbs/ in. range.

I am trying the UMI Performance 1" lowering springs that are 600 lbs/ in. front and 130 lbs/ in. rear.
I'm making several other changes that seem to be taking forever so I don't have any drive info yet.

Another thing to consider is old stock springs have sagged an inch or better over time and new lowering springs may leave the car the same height or taller than the springs you have now.

Here's a link to the Moog spring chart. https://www.moog-suspension-parts.com/universal_coil_springs.asp

You can scroll down by part number and look up the specs.
 

jshot

Member
Aug 8, 2018
76
10
8
37
Ontario, Canada
It seems most list the 5658 fronts, 1" drop 530 lbs/ in. spring rate and the 5413 rear, 1" drop 167 lbs/ in.

These may be a bit stiff for you, however I like more of a Z28 or GTA ride and have had some ATR performance handling springs in the past. Although not listed, I think by the wire diameter the springs were in the 530 lbs/ in. front and 125 lbs/ in. range and even with bilstiens I thought the front was a little soft.

The 167 lbs/ in. rear springs may help plant the tires at the strip, but I feel they would throw off the balance of the car handling wise.
I would not be afraid of the 530 lbs/ in. front springs especially with softer shocks if you could find some rear springs in the 120 lbs/ in. range.

I am trying the UMI Performance 1" lowering springs that are 600 lbs/ in. front and 130 lbs/ in. rear.
I'm making several other changes that seem to be taking forever so I don't have any drive info yet.

Another thing to consider is old stock springs have sagged an inch or better over time and new lowering springs may leave the car the same height or taller than the springs you have now.

Here's a link to the Moog spring chart. https://www.moog-suspension-parts.com/universal_coil_springs.asp

You can scroll down by part number and look up the specs.
i have been reading a lot about moog, and yes the 5658/ 5413 has been thrown out a lot. and i have also been interested in the umi rear 1" let me know what the out come is. i'm not afraid of stiffening up a bit, but i do like a comfortable sunday drive. i am going to keep searching.
 
  • Like
Reactions: 1986 Buick GX1
Top Bottom