what should be the inside diameter, in inches, for the springs?
also, what is meant by 'hypercoil'?

depends, what are you trying to do??

stock dia. is approx 4" for the ID

hypercoil is a brand name I believe...marketing name, sounds cool I guess

the aftermarket adjustable spring perches use a 2.5" spring (ID)

muller,
thanks,
but why the diff in sizes from stock to aftermarket, and is there any modification required to change to the 2.5in?

the 2.5" size is kind of a "standard" size for race/aftermarket applications....this size allows the spring to be very close to the shock for better packaging.....a spring of larger overall diameter is just taking up "space" and does nothing benificial that the smaller spring cannot do.




in the picture, you'll see a Bilstien shock with a threaded sleeve and collar....the threaded sleeve is slid over the shock, the collar allows one to fine tune the ride height

in order to switch over to the coil-overs you need the sleeve, collar, spring and a top piece which holds the top of the spring.

What kind of shocks do you have? the cheaper brands have a spring perch that you cannot remove....I highly recommend Koni Yellows, some people like the Bilstiens....

I have a set of yellow bilstien rears that have adjutable perches that use the larger springs. They are only adjustable in steps though (has a set of grooves in the shock body, pick a groove that's closest to what you want, not infinitely adjustable)

QUOTE (bondo @ Feb 2 2005, 03:32 PM)

I have a set of yellow bilstien rears that have adjutable perches that use the larger springs. They are only adjustable in steps though (has a set of grooves in the shock body, pick a groove that's closest to what you want, not infinitely adjustable)

the shocks in the picture have those snap ring grooves as well....okay for gross adjusment, but not very practical for corner balancing or fine tuning the ride height

mike et al; do you know off-hand what the appropriatte I.D. of the threaded collar is for the Bilsteins? coleman racing sells them in 2.04 and 2.08....

http://www.colemanracing.com/catalog/index...hp?cPath=49_427

patrickmotorsports.com offers a nice 2 1/2 inch coilover package for teeners. I am pleased with the one I bought.

no idea on the diameter... eBay has some dirt cheap kits...for $70 bucks including shipping, you can have enough parts for 4 shocks....not a direct bolt-on, I'm sure you'd have to modify the top hat for the spring....

If i picked up 175lb coils, 2 1/2 inch, what then should be 'package ?"

QUOTE

If i picked up 175lb coils, 2 1/2 inch, what then should be 'package ?"

10" free length springs seem to be a good all around choice in length

see the post above for the coleman racing products that Nathan posted, those are the parts you need (one pair), I do not know what size or the exact diameter needed....you'll have to measure your shock

do you have a stiff front bar or upgraded front torsion bars?

175 is pretty stiff if the rest of the car is bone stock