Justa car guy

Hi THere

I own a 1970 olds Cutlass Supreme. Want to replace springs all the way around. Would like to raise the car slightly, but if not, a mild performance spring would be good. No intent to hot performance the car, other than headers maybe. Car has 47000 miles, just trying to give it a bit of a lift and a little more agressive stance.

Any suggestions on good springs, or good performance springs would be appreciated.

THanks in advance

Justa car guy

RetroRanger

I have a 72 supreme. I put the moog HD springs on mine. they are similar to the fe2 spring rates and inexpensive at less than $200 for all four. I got them from rockauto if you search on here you will find the rockauto discount code and many others who have used the moogs

I also added a 1.25" fr sway bar and 1" rear bar at the same time as replacing the original springs on my car so the difference was night and day but not all due to the springs.

IIRC the fr spring was the 5450 and the rear was the 5385

Justa car guy

EXCELLENT!!!!

Thanks for the reply. I came across exactly those springs and wondered about them, and they look like the ticket. I had also pondered sway bars for the car, and your reply answered that. See what you've done!!

Very much apprectiate the information.

Justa car guy

Fun71

Some time back I asked for suggestions for front springs on the Olds e-mail list and got the following information:

> 5390 small block - no AC
> wire diameter = 0.650"
> load height = 11.000"
> load = 1952 pounds
> rate per inch = 336 pounds
> free height = 16.808"
>
> 5382 big block - no AC, small block - AC
> wire diameter = 0.660"
> load height = 11.000"
> load = 2066 pounds
> rate per inch = 360 pounds
> free height = 16.724"
>
> 5400 big block - AC
> wire diameter = 0.660"
> load height = 11.000"
> load = 2167 pounds
> rate per inch = 360 pounds
> free height = 17.004"
>
> 5536 442 small block - AC - heavy duty, 442 big block - no AC - heavy duty
> wire diameter = 0.690"
> load height = 11.000"
> load = 1984 pounds
> rate per inch = 488 pounds
> free height = 15.063"
>
> 5450 small block - AC - heavy duty, big block - no AC - heavy duty, -442 big block - AC - heavy duty
> wire diameter = 0.690"
> load height = 12.000"
> load = 1642 pounds
> rate per inch = 454 pounds
> free height = 15.616"

I picked the 5536s based on the higher spring rate and 1" lower ride height.
They are much stiffer (488 lbs/in) than the original springs, yet they give the same ride height as my worn out 34 year old originals. The data book showed the ride height to be 1" lower than the factory Cutlass/convertible springs - 11" vs 12". I researched the rear springs in the Moog data files and found the 442 rear spring applications are 1" lower, too, with higher spring rates than the "regular" cars. I do not really know the specs on my rear springs as I got them through PST a long, long time ago and they were advertised only as "442" springs. I think they are the equivalent of the Moog 5409 springs:

> All 442 applications
> wire diameter = 0.554"
> load height = 7.50"
> load = 847 pounds
> rate per inch = 143 pounds
> free height = 13.44"

Here's a side view showing how the car sits with the new springs:
P2250124.jpg

It definitely sits lower than other Cutlasses. I was parked between another '71 convertible and a '70 at a recent show and my car was the lowest one in that lineup.

oldcutlass

Kennth I think your cars stance looks perfect with those wheels and tires.

Justa car guy

Thanks for the detailed technical response, and personal anecdotes. I had originally thought of having the same ride height all the way around, but after seeing yours, a slight nose down looks great. Its amazing to me the slight differences in springs required for different years. Another reply listed Moog springs for a 72 Cutlass, which appear to work on the 72 and 71, but not the 70, so there is a different serial number for the 70, but they could be the same spring for all I know. Seems like you have to dig into each spring technical spec, to get what you want. Which you have done.

A fabulous looking convertible by the way.

gearheads78

Nice forum handle HAHA. I've seen that somewhere before.

Justa car guy

I KNOW!!

I've had a couple guys mention it!!! I am going to change it ASAP!!! First grab on my name list when I first enlisted in the forum.

gearheads78

Its no big deal man. Use what you want to use. The quote came from a thread that a member once used on me like it was a negative since I don't eat breath and sleep only Oldsmobile. I liked it so I addded it to my sig.

Fun71

I didn't shoot for that, it just came out that way. The sprigs I selected were the HD 442 springs that were supposed to be 1" lower ride height than the regular Cutlass springs. From what I remember, the rake is about the same as the other Cutlasses I have parked next to at shows - mine is just a bit lower all around.

Within the same year, too. So many things dictate which springs are used, such as the vehicle weight due to various options and the desired ride firmness. That's why I started by researching what springs the car had from the factory and then used that as a starting point for new spring selection.

They will definitely interchange. Perhaps there is some difference in vehicle weight between 70 and 71/72 that translates to different spring numbers.

oldcutlass

The link below is moogs list of part numbers and technical details on thier springs. What you look for on the fronts are ID, load rate, length, and end type. This what I use to determine height and ride charactoristics compared to what the so called stock part numbers that had been recommended. You can sort this list by any column.


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