[Chirodan]

I want to buy new springs, but I need to know what the stock height of the OEM springs are b/cuz I want to lower the car by 2". That way I will know what size springs to buy and I will have more control over the spring rate to get (400-500/in.).

I am going to buy asap, so if anyone can help, I'd appreciate it.

[Chirodan]

I want to buy new springs, but I need to know what the stock height of the OEM springs are b/cuz I want to lower the car by 2". That way I will know what size springs to buy and I will have more control over the spring rate to get (400-500/in.).

I am going to buy asap, so if anyone can help, I'd appreciate it.

[Steve C.]

From the MOOG replacement springs specification sheet for Firebird.
400 with air & 455 without air(#5376):
Approxiamte free height 17.917, 0.677 wire dia, 12.0 load height, 1885 load & 318 rate load height.
400 without air(#5384):
Approximate free height 18.105, 0.672 wire dia, 11.5 load height, 1942 load & 294 rate load height.
455 with air(#5402):
Approximate free height 17.693, 0.690 wire dia, 12.0 load height, 1908 load & 335 rate lode height.
If interested, the #5276 is the v-6 (no air) spring with a approximate 17.099 free height, 0.660 wire dia, 10.5 load height, 1981 load & 300 rate load height.

[Chirodan]

Thanks for the info Steve,



so if I want to buy some higher rate springs, but lower the car in the same process, should I go by the "free height", or the "load height"?

I will be going by the 400 w/ air information.

[Chirodan]

I want more of a sporty feel, so what spring rate should I go w/? 450 to 500?


what website can I go to that I can have more info on spring height and rate?

I was looking in summit's catalog and they have Qa1 springs that go by height and rate. Is it safe to buy those springs w/out the shocks/coil over kit, or are they only for that application?

thanks guys...

[Steve C.]

At the time my '70 TA had the origional 400 with no air. I found a commercial distributor that specialized in selling chassis parts and borrowed the MOOG replacement catalog and looked in the coil spring specifications section for Firebird. He was kind enough to make a copy of the appropriate page plus I got the commercial Moog Tech Line phone number from the catalog.
I was interested in trying to drop the nose for apperance reasons only and wanted to minimize any increase in stiffness, I was interested in drag strip performance and was not interested in a canyon carver. I ended up installing the Moog v-6 #5276 springs, but they only dropped the front about 1" or so.
At that time a person at MOOG tech stated (opinion?/need to varify) that their #5642 spring would lower it by about 2", but it had a 420 rate compared to the v-6 springs 300 rate.
Specs on #5642 spring:
4.080 I.D.(as are the others mentioned above), 0.690 wire dia, 11.00 load height, 1860 load (amount of weight to spring at load height), 420 rate at load Hgt, 15.389 approximate free Hgt.
Please keep in mind this information is old and may not be current.

Today I still have the same v-6 springs but the front nose has come up again due to weight loss on the front over time (remove PS, PB, alum heads,'glass hood, etc). I don't like the nose high apperance but I haven't bothered to change them. Plus the ever present header collector clearance issues !

[Chirodan]

I just want a decent sports car feel. Currently too much bounce and slop to control.

what is pricing like, and where can I get them?



Does MOOG do the same thing for rear leafs?


thanks for the info btw.

[Steve C.]

I suspect MOOG chassis parts is a aftermarket division of Federal Mogul, they have the same part numbers. But I'm not sure especialy the way the automotive supply industry changes so often.
Stop by or call your neighborood NTW dealer or shop, or similar type place, they can refer you to the local shop that sells commercial chassis parts. That's who they buy from locally. Just explain what your after, just info, not trying to purchase direct from the wholesaler.