Zuba951

LOL.. This is actually wrong the 944 TURBO CUP FRONT is the ESCORT CUP and is 600/180 or 6000/1800 they use to drop the 0. The FIREHAWK FRONT IS 380/150 with the 400/200 rear shocks. The fronts were valved for 300-400lb springs and the rears were valved to use with the stock rear torsion bars 86-89. The rears are very stiff and lock the back end together. I have the FIREHAWK setup on my car with 300lb springs up front with the stock torsion bars and the 400/200’s in back. For street and some DE I think they work great. The car rides very firm and the back doesn’t bob when I shift. Years ago I had the pleasure of speaking with Jack at Bilstein. He was the only person there that knew anything about these shocks. He is not there anymore. He told me all about the shocks. Now LR sells all kinds of packages to give you a better price, so if you get the firehawk fronts with the escort rears you need to figure out what springs you are going to use and have them revalved by Bilstein. (They are non adjustable)

Brian

Zuba951

[QUOTE=robstah;9525404]How is that wrong? Those valvings come STRAIGHT FROM BILSTEIN. And saying that the shocks are setup for 300 front and what is an effective 126 rear (300lb coilover spring comparison) is so far off base it's not even funny.

The Bilstein Catalog is WRONG!!!!. They mixed up the names and the rear shocks. There are two setups. The front struts are exactly the same The Escort Cup are valved stiffer (600lb spring) they go with the coil overs. The Firehawks (300-400lb springs) go with the shocks. If you don't believe me just look at the numbers. Why would you put the stiffer rears with the weaker fronts?
As far as the rears are concerned ...Yes I know if you just do the math it doesn't work...But that’s how it was designed and it works very well. The rear shocks are very stiff in fact I asked Jack at Bilstein if I could use them with 29mm rear torsion bars and he said NO they would be too stiff.

hp18racer

Street/Track Car 250 front/350 rear, no t-bars.
Club Racer 600 front/900 rear, no t-bars.

chrenan

Street/Track 250 front and 200 rear helpers with torsion bars.

Koni adjustables at all corners.

67King

Wow, three pages of advice and arguments, and we don't have a clue what tire sizes you run. That's probably the most important input.

bw993

400lb front and 600lb rears, no t-bars

dillon410021

I will be running 18x10(255/35/18 tire) in front and squeezing 18x11.5 (285/35/18 tire) in rear
tires are just estimates as I havent bought them. The fronts and rears will be stretched a bit

ausgeflippt951

Wow I missed this gem of a thread. As much as it pains me, I'm not going to bother contributing for fear of getting yelled at...oh and the fact that I've never personally used the Bilsteins!

Dillon, will the car be exclusively a track car? Mine is a dual purpose car and I run 350#/30mm setup with revolved koni yellows. Don't think this gives you much help but I can offer that this setup offers loads of fun on the track and is about as stiff as I would want to go for a street car. (You can use your g/f as a gauge -- if it's too stiff she'll let you know!)

ausgeflippt951

Meant to say my Konis are reVALVED, not revolved. Damn autocorrect.

xsboost90

all i can add is that when i owned this car it had 525lb rear coil overs and 400lb front springs. I liked the balance very much on the track and was getting into the 1:42/1:43 range on the club course at Mid Ohio on street tires.

67King

When I ran 245's square, I was 600 in the front, 550 in the rear. Now I am 245's in the front, 285's in the rear, and had to seriously increase my rear spring to get it to stick in some places. Now running 850's in the rear. Running Leda single adjustables (Leda uses a heavier oil, and therefore requires less spring than stuff like Moton). While there are a lot of other factors like dampers, weight distribution of the car, sway bars, etc. I would think a 350 pound spring in the front would be a good match.

Of course, if you really want to get an opinion from someone who knows what they are talking about, you could call Racer's Edge and buy the springs there.

Laust Pedersen

The effective spring rate is equal to the spring rate times the displacement ratio squared, where the displacement ratio is defined as the spring displacement divided by the wheel displacement.

Numbers have been flying around in this thread, but let’s take the example, that the spring rate is 500 lb/in (which confusingly in common parlance is called 500 lb) and the wheel moves 1.25” for a 1” compression (or expansion) of the spring around its resting point. The displacement ratio then is 1”/1.25” = 0.8.

For a 1” movement of the wheel the spring changes height by 1/1.25” = 0.8”. Since the spring is very linear (non-progressive) it exerts a force of 500 lb/in * 0.8” = 400 lb on its mounting point. In this case think of the suspension as a lever for the spring and wheel mounting points and realize, that the wheel sees an effective 400 lb * 0.8 = 320 lb. So it takes 320 lb to move the wheel 1”, hence an effective spring rate of 320 lb/in.

In essence we have multiplied the 500 by 0.8 twice, which is the same as writing 500 * (0.8)^2 = 500 * 0.64 = 320, which is where the square of the displacement ratio comes from.

I hope this helps more than confuses.

Laust

kinglenario

Yeah just call Jason at Paragon or Karl at Racer's edge. They'll set you up.

Chris Prack

Well it's good to see nothing has changed here. lol Great thread. I'm staying out of it. At least for now.

Van

Sorry to tune in late...

The front motion ratio is 0.91 and the rear is 0.63.

These are calculated by taking very careful measurements - I raised up the wheel exactly 1" and measured exactly how much the shock compressed.

Now, these measurements are probably a little different for early offset cars and cars with steel rear control arms...