Coil-over spring rates - Help or...keep factory A Arms and springs

[HECDOGGIE]

Need help picking the right spring rate / Coilovers.. Or stay factory A Arms ?

Car - 93 Mustang
Will not be road raced - Will not be Drag Raced

I am going with a Team Z K member to free up room, on top of the fact that its way cleaner than a factory K.

I have tubular A Arms, however, i am not 100% convinced that going tubular a arms is the way to go vs a coil perch and factory A Arms.

I am leaning towards Coilovers @ 12" 250 lb... does this sound right ?

opinions please...


Thanks

[91CoupeMike]

I was going to use a 14 130 for the front of my car.

The coil overs free up friction in the suspension vs coil and perch.

If you decide you want to keep it stock you may need to modify the stock a arms to fit in the k member properly, and I'll be interested in your tubular arms.

[86lxttop]

you wont be able to lower your car very low with 14inch springs...

[91CoupeMike]

you wont be able to lower your car very low with 14inch springs...

Damn I was hoping I could adjust them down.

Good thing I haven't ordered anything yet.

[Trick Pony]

you wont be able to lower your car very low with 14inch springs...

Not necessarily true. The compressed length of the longer, softer spring he mentioned could actually be less than the compressed length of a stiffer, shorter spring.
Let's say his car has a corner weight of 800 lbs on the fronts.
A 14" 130 lb spring would actually have a compressed length about 1" shorter than a 12" 250 lb spring.

[Trick Pony]

Need help picking the right spring rate / Coilovers.. Or stay factory A Arms ?

Car - 93 Mustang
Will not be road raced - Will not be Drag Raced

I am going with a Team Z K member to free up room, on top of the fact that its way cleaner than a factory K.

I have tubular A Arms, however, i am not 100% convinced that going tubular a arms is the way to go vs a coil perch and factory A Arms.

I am leaning towards Coilovers @ 12" 250 lb... does this sound right ?

opinions please...


Thanks

It sounds like you don't want one extreme or the other as far as drag or roadrace but you need to decide what combination of ride vs handling you are looking for.
The benefit of coilovers is reduced unsprung weight, better handling, and better ride for a given wheel rate.
A 250 lb/in coilover has a wheel rate of about 225 lb/in. Factory Cobra front springs are 425-530 progressive according to what I could find, so with the factory motion rate you are talking about roughly doubling the wheel rate with that front coilover.
I can tell you from experience that 250 lb/in front coilovers ride very well on the street, 350 lb/in are tolerable, and 450 lb/in are very rough.
You didn't mention what you plan to go with on the rear but you would need to select something well matched to the front or you would have seriously unbalanced handing.

[HECDOGGIE]

I can tell you from experience that 250 lb/in front coilovers ride very well on the street, 350 lb/in are tolerable, and 450 lb/in are very rough.
You didn't mention what you plan to go with on the rear but you would need to select something well matched to the front or you would have seriously unbalanced handing.

Right now it has eibach springs. However, I plan on LCA's..

What would be the equivalent to 250lb coilover set up up front ?

Great info btw.

[Trick Pony]

Right now it has eibach springs. However, I plan on LCA's..

What would be the equivalent to 250lb coilover set up up front ?

Great info btw.

I think for stock location springs and the standard 4-link configuration (no Watts link or Panhard bar) a 250 lb/in out back would be about right but I can't recall for sure. I'd call somebody like MM or Griggs and ask what they recommend.