Serge944

Maybe 200# effective in the rear in addition to the torsion bars. This is about a 350# spring or so.

Maybe I'm missing something, but as far as I know, running 350# springs up front and 200# in the rear is just plain WRONG.

Heres a write up on this matter from our very own Paragon Products: http://www.tech-session.com/kb/index...x_v2&id=22&c=4

Sweet 944

Thanks serge.. that is a great write up.. I am starting to understand this...

joseph mitro

ok, lets add up his rates:
F = 500lb;
R = 123lb+(0.6 x 350lb) = 330lb (or 385lb using conversion of 0.75)

that sounds like a balance towards understeer, but you can dial that out with alignment, sway bars, and tire pressures. assuming 350F and 200R:
F = 350
R = 123+(0.6 x 200) = 250

i've got 350 front, 300 rear (126 + [0.6 x 275]) with 27/19 mm sway bars. it's stiff but still streetable. using the above spring rates will be an unbearable street ride IMHO

Sweet 944

Joe.. so your rear springs are 275 right, is this for street?

The fronts I have are actually 550# way to heavy...
I am going to work with theis set-up.. get some springs and sway's...

Serge944

If I was in your shoes, Id do 250# fronts and 200-225# rear springs. Then the stiffest swaybars you can afford!

Your car will be plenty flat and responsive, all while maintaining contact with the road over imperfect roads.

joseph mitro

yes, they are 275 rear coilovers plus the torsion bars. total rate about 300lb. it's a bit stiff for the street, but i can tolerate it.

if you have coilovers you can easily swap out springs until you find the right setup for you. also, what works for one person may not quite work for another due to different driving styles on the track.

AJBERB

Here's a crazy idea... call TRG and ask them.

Then let us know what THEY say. They sold it and should have a really good understanding of its intended applications.

Sweet 944

Yeah.. I am in the process of calling Bilstien USA. I am going to have to send everything out to be revalved anyway.

I just wanted to get some Porsche guy opinions first...

Thanks to everyone for advise.. I really think I'm getting a grip on this..

I will let you guys know what I decide to go with and what the outcome is.. ride, handling, etc....

Peace.....

Sweet 944

I have one more question regarding my suspension upgrade.

I am using the tech sheet form Paragon - http://www.tech-session.com/kb/inde...ex_v2&id=22&c=4

I hope I am getting this right but wanted another opinion.

Here goes..

I have 350# springs that I want to use up front.

Do I calculate the effective rate of the 350# Coil Spring Rate (which is 197# effective rate according to the tech sheet.) as my desired rate for the rear or do I use the 350# Coil Spring Rate?

EXAMPLE:

(197 - 126)/.56 = 127 or so.. this means I'll need a 100 - 125# coil-over spring to achieve the 197# effective rate.

-OR-

(350 - 126)/.56 = 400 This means I'll need a 400# coil-over spring to achieve the 350# Coil Spring Rate.

Manning

I think the effective rate for springs up front is higher. On the rear it is something like 56% effective but on the front it is closer to 85% or more, I don't recall exactly. The rate chart in that tech session is for rear coil applications using the 56% effective rate. So your 350lb/in front spring have a rate more along the lines of 297lbs/in if I am thinking correctly. So your formula will be:

(297-126)/.56 = 305 or so.