[68bird400HO]

When I ordered my leaf springs from Eaton for my '71 TA about a year and a half ago, I used their application chart which is based on the original GM blueprints since Eaton was the supplier. Their chart showed that the 1970 and 1971 Trans Ams used different springs on the left and right. One spring had about 3/4" more arc in it. Their chart also showed that the '72 and later TAs used the same springs on the left and right. Looking at NJSteve's thread, I thought it would be cool to detail my springs by spraying the factory part number on them. Steve was very helpful and emailed me some pictures to make the stencil with. As I started doing this I remembered having to order different springs for the two sides so I figured I would check the parts book. It showed 481612 as the spring number for L and R for 1970-72. .....hmmm.....is Eaton providing mis-information??....... As a second check, I dug out my original springs and, with some scuffing, was able to find the part numbers. Sure as heck, they are different and the one spring does have more arc in it. I am sure these are the original springs from my car. The one part number is 481612 PL and the other side is 482547 PM. I also noticed that the number font is smaller the Steve's '72 springs. Also, with all of the paint/overspray discussion going on, I will add that the bottom side of the spring has definite black paint on it from the VN black spray procedure, but the top side of the spring shows no evidence of any paint.

Just thought I would share this info with everyone.

[njsteve]

Check it out:

If you look closely at this upside down flipped photo of my original right hand spring you can see that they painted over a previous part number with a "2547 PR" still visible...under a larger PL painted code!

Looks like we solved the mystery - they just reused and relabeled the earlier springs with a single part number!

[68bird400HO]

Originally Posted by njsteve

Check it out:

If you look closely at this upside down flipped photo of my original right hand spring you can see that they painted over a previous part number with a "2547 PR" still visible...under a larger PL painted code!

Looks like we solved the mystery - they just reused and relabeled the earlier springs with a single part number!

Did your left spring also have the larger number painted over the smaller one? Also, did you check you springs to see if they had different arc heights?

[njsteve]

Couldn't find any paint marks on left spring.

The car sat perfectly level with the original factory front and rear springs and I re-used them after dissassembling, cleaning and reassembling them. There's nothing like the original GM parts (when they're not worn out). The one thing I can't stand is seeing these cars sitting at some crazy four wheel drive ride height with 6 inches of wheel well visible over the top of the tires.

[Norwood]

Originally Posted by njsteve

The one thing I can't stand is seeing these cars sitting at some crazy four wheel drive ride height with 6 inches of wheel well visible over the top of the tires.

That is 100% correct. Over the winter I will be replacing my 4 wheel drive springs. When I replaced the springs back in about 1985 I hoped it would settle a little bit more. I am still waiting

[njsteve]

No offense meant, Sir.
I didnt mean to pick on your car.
:-)

[68bird400HO]

Just tonight I was flipping through the 1971 Firebird Assembly Manual and checked the rear suspension section. There it was, rear leaf spring for WS4 right-482547 left-481612.

[Transamric]

Norwood, that doesn't look as bad as some I've seen with replacement rear springs. Kind of has a more period appropriate slight forward rake.
But ditto the "sky-high 4x4 attitude (altitude) of some "correct" restos. Especially with the rocker to ground clearances given in the Shop Manuals.

[Norwood]

Ric, Mine is not as obnoxious as some but still sits WAY higher than before I changed them

[thefirebirdm@n]

Hey Norwood, I didn't think it looked that bad either but it may be that I love those blue cars so much my eyes keep drawn to look at other parts of the car, lol. I too hate the look you guys are talking about. Seems about once or twice a month I'll look at a TA on ebay with the afore mentioned 6" between tire and fender whell. It just ruins the entire look of the car.

Since we're talking about this does anyone know what that distance should actually be? The distance between the top of the tire and the fender lip? I think my '73 looks good but I've been thinking about dropping it 1" all around as I've seen a few dropped a 1" tp 1.5" and think it looks great.

[Transamric]

Craig got me thinking maybe I need to go & take a straight side shot pic of my Blue '70 to see how it compares with his. Then I remembered,....................it's up on blocks for the winter!! DOH!!

[GETRIDAONE]

Originally Posted by thefirebirdm@n

Hey Norwood, I didn't think it looked that bad either but it may be that I love those blue cars so much my eyes keep drawn to look at other parts of the car, lol. I too hate the look you guys are talking about. Seems about once or twice a month I'll look at a TA on ebay with the afore mentioned 6" between tire and fender whell. It just ruins the entire look of the car.

Since we're talking about this does anyone know what that distance should actually be? The distance between the top of the tire and the fender lip? I think my '73 looks good but I've been thinking about dropping it 1" all around as I've seen a few dropped a 1" tp 1.5" and think it looks great.

There is no set measurement for tire to wheel opening. The only references are from the ground to the rocker panel at front and rear. It would depend on the size of the tires and sag of the old springs as to how the ride stance looks. I put new front and rear springs on my 70 Formula during the restoration. The front was way higher than the rear. I put the old springs back in the front and it dropped a liitle over 2". The rear leafs have settled some after putting some miles on it.

[CaptCrunch]

Originally Posted by Norwood

Ric, Mine is not as obnoxious as some but still sits WAY higher than before I changed them

Doesn't look bad to me either.......that being said, I re-used my original front coils and re-arched the rears. It now sits a little too high in the back.

[JRS704]

Which spring has more arc in it? The left side or right side? I have both springs disassembled and ready for resto. Definitely a 3/4 difference in the arch. I can faintly see painted on part#'s, however not clearly. Any help would be awesome on this one. Thanks

[Formulabruce]

DS for the bigger arch. Try to get the other leafs tested and make a similar "pack" for each side.
GM Changed the upper control arm mounting Arms ( steering) and the rear leafs to accommodate new Road crowns, and Radial tires.
There was no longer a need for a difference in springs as alignment and radials could make up for it.
I always put on 1973 ( single part number) 4 leaf , around 126 lbs springs. This allows some movement, even with the rubbers in the eye and shackles.
Firebirds are always heavier on the DS, so Big arch there.

[JRS704]

Awesome! Thank you for the info. I did have another question and most likely many more. Are there any suggestions on retaining clips for leaf springs as to where I can purchase? Thought I noticed on some other threads that there were a couple members who actually produce them?