I'm doing some suspension work on my 77 and as part of that, I'm replacing front struts. Question is... Is there any way to tell if my springs are stock or aftermarket?

The reason I ask is that my PO sprayed the entire underside black, but my spring compressor scraped off a little of the black coating that the PO put on there, and the springs are red underneath the black.

I always thought the springs were stock, but who knows what the PO(s) did. And of course, its always possible that a PO painted the stock springs red, right? I found Koni inserts in there now, so its clear that PO's have been in there before me.

Hence... Are there any markings or telltale characteristics of the stock springs that would identify them as factory instead of aftermarket? Number of coils? Diameter of the wire used? Top or bottom coil design? Anything?

I went and looked at mine, 355,000 something serial number, the strut housing? is a dark blue under all the grime. And the funny thing is, my front passenger side spring has about 3 coils that are red the rest is either black or dark blue too. If you'll tell me where to look I'll be glad to or take some pictures.

Cliff

Specs for a 260z front springs is .453 dia. 15 inches free length. Number of turns 10 3/4 inches.

Don't know if the 280z is the same.

Edited February 10, 201411 yr by olzed

I've had a couple of stock spring sets off and they were black with a colored stripe, about one inch wide. I assume the color had some meaning.

Red might be Tokico. It's a bright red. I would test a section of paint with some acetone, MEK, or similar and see if the black is soluble. Don't know for sure but the manufacturers probably use a two-part epoxy or urethane, or a powerdercoat, that wouldn't be soluble. If you're lucky the white ID numbers are two-part also. 5022-F and -R are the 280Z Tokico lowering spring numbers.

The stock 77 springs jack the back of the car up pretty high. If your springs were stock you would probably notice.

Thanks guys. I've seen a couple of pics of what were supposed to be 280 front springs and in the pics, there are 11 turns. The FSM says 9.5 active turns. I'm assuming the last turn+ on each end isn't active.

I'll count the coils and measure the diameter and post my results.

BTW - My PO's skills left a lot to be desired. Everything I take apart has issues, and the struts have been no exception.

Here's another clue - the stock springs have quite a bit of preload. You would have had to crank the compressor down quite a bit before they could be set free. The Tokico springs barely have any, just enough to fill the space. You can press the top hat on by hand, it you have the weight, if I recall right. I have them on the back of my car, the front is waiting.

I've got both front struts apart now and my springs have 11 (full) turns and had lots of preload when installed, so I know they aren't the shorter Tokiko springs that I've seen pics of. At this point, I'm guessing they are stock and that someone (maybe two PO's ago) painted them red.

And to my surprise... The second strut was actually put together mostly correct. Top perch wasn't lined up correctly with the first coil, but at least the order of assy was correct on the second side. That's better than what I found on the first side!

Have I mentioned that my PO has made some mistakes?