Just wondering if anybody know the spring rate of stock IROC coil off the top of there head?

I don't have a third gen, but I do have a set of coils out of my old 86 iroc.

 

Hard to say, depends on the spring code, car's options, etc. Most were 550lb/in front, 130 lb/in rear. Unless they came off of a super low mileage car they've probably sagged and fatigued some over time.

 

550 is it? I figured they would be alot higher rate than that. Guess I'm better of with my stock S10 coils at that rate... LOL

 

Moog sells replacement springs at like $50 a pop and you can get 700 lb/in rates and other companies sell similarly priced springs with even higher rates. Unless your springs are super low mileage (<50k miles) I'd sell them to some kid trying to do a v8 swap on the cheap or scrap them. Not a lot of benefit/ demand to old worn out springs when you can get two brand new ones and some stickers for around $100

 

Stickers are good. LOL

I've been told some stock S10 coils are upwards of 700lb/in. (707 and 748 to be exact).

I'll probably just use my stock coils and cut 'em to get the ride height I want.

Unless F bodies have totally junk springs, I can't see 'em sagging alot. I'm sure they will sag some and lose some strength, but not alot.
My old 93 C1500 has 454+ thousand miles on it and it might sit an inch lower than stock, (not counting the lowering spindles). Granted it's not a corner carver or anything close, but it does have twice the miles on it that a normal high milage car would have. LOL

That 100 bucks will buy me a roll pan..... LOL

 

No, not exactly...

Actually, those are the rates out of the Moog catalog for the 5662 and 5664 springs, which do indeed happen to fit S trucks. (and F bodies, and A & G bodies, and prolly a whole lot more besides) But they're not "stock" in anything.

The IROCs usually measured nearer 450 by the dinking-around method; (set heavy stuff on it and see what happened) but after however many years, who knows how much they'd lost.

 

Actually the S10 coils figure up mathmatically as 754 lbs/in.

Good little read here;
http://www.bluecoilspring.com/rate.htm

Found that while searching for how to count active coils.

 

For a stock S10? All of the ones I ever drove rode pretty soft imo and there's a lot less weight acting on the front end with the little iron duke or the 60* v6 than there would be with a v8 which wasn't a factory option.

 

That was exactly what I was thinkin myself. That's why I kept these IROC coils layin around all these years. LOL

But according to the number the S10 coils would be great cheap lowering coils for an F body.