Porsche Enthusiasts Club Forum

can anyone suggest spring rates for fast road use for a 944 turbo (coilovers front and rear)

For fast road, especially if you have lightened the car, I would probably go for around 200lbs/in maybe 220lbs/in, which for some may sound soft, but combined with some decent anti roll bars will keep the car flat through the corners and will not loose traction just because the country lanes your enjoying at the time has an uneven surface, which can ruin your enjoyment of fast road use.

This is exactly the same spec I tend to use for the cars we setup and look after that go to the ring on a regular basis, as it needs to be setup more for rough surface fast road, which is a bit like UK roads are like these-days!

For the back, it all depends if you are keeping the torsion bars or not, if you are, you only really need a 50lbs/in rate and reindex the torsion bars so that with the coil-overs pre-loaded when raised, give you the desired ride height when on the ground.

I would also not recommend lowering the car beyond 13 inches from the wheel centre to the front wheel arch centre, unless you are going for aftermarket wishbone ball joints, but also beyond this level of lowering, you will not have the squat when on the power for weight transfer and will not have enough travel on the rear for a combination of squat and rough surfaces, which will see you scrabbling for grip.

This might not sound a very sexy setup, you will hear of people recommending 400 lbs/in springs, but you will be slower with that kind of setup in almost every condition than a on a very smooth track, but also you will find yourself lifting wheels and having weight transfer issues.

What rate are the adjustable koni? Not sure if it worth getting my gaz golds moved over, with new softer springs. As well as my ps rack and poly bushed wish bones.

How much would it cost 2 have my koni rebuilt and set up?

Thanks

just ordered the Spax RSX118 coilover kit (inc rear coilovers)

http://www.design911.co.uk/fu/prod13159 ... RBO---968/

I've been hearing good things about the SPAX RSX kit for a few years now so it would be interesting to hear how you get on. Going back to your original question, what spring rate are they coming with?

Not sure off the top of my head what rate the KWV3, Spax, or Gaz items are as standard, but I believe these all use off the peg 2.25" or 2.5" ID springs, so you can put the ones that come with them onto ebay and order some specific ones that you want.

Standard 944 springs, off the top of my head, are about 165lbs-in springs, but what most people actually want (if they know it or not) for road use is typically a slightly stiffer spring, much more modern damping valve technology and less roll.. upping the spring rate helps with roll, but add some improved anti roll bars and 220lbs-in springs and you will have a car which is totally flat on cornering, will have much reduced dive, enough squat for weight transfer on hard acceleration, and all 4 wheels will have maximum response to keep all 4 wheels in contact with the ground even when driving on the limit on differing road conditions.

On the other hand, what some people want is rock hard suspension and that "too fast too furious" blurred vision, loose fillings experience, which is really slow on the road with poor grip and poor weight transfer.. For that, just weld up your struts, same effect, much less cost!

no idea what they come with, the bloke at the shop ive ordered them from said he didnt know.... haha

i suppose i could email Spax themselves and ask, i would hope they would know!

should have them Monday/Tuesday with any luck, ill get some pictures of the "kit" before its fitted

Not sure what my gaz where, but u couldn't rock the car from outside.

Iv spoke with gaz and asked them what rate they likely where or if they could tell me away 2 find out? They sirguest I could get new spring £22 + vat per side. Recommened 325lb front 225lb rear? Surely with the torson bars the rears should be more then 100lb less? So Iv still no idea if what I got are 400lb odd or not.

I think a progressive spring would help, slightly softer on small bumps e.c.t

So can I fit any spring if the height and diameter is right?

325 lbs-in at the front is good for a track focussed car, something that may drive on the road to and from the track, but is more of a track car than a road car.

400 lbs-in for a race car, more for smooth circuits.

For any of the applications I tend to recommend keeping the rear slightly soft to help weight transfer on launch, during and exiting corners.

I asked 4 fast road use, and choice the gaz as I was lead 2 believe u could adjuset them in moments 2 suit, not really the case if Iv got 400lb spring rates. Felt like the adjuement was noticeable but didn't work well withing the rate off springs. I explained 2 gaz that I wanted 2 keep a level off comfort that could be tune in and out, and they came back with 325lb sirgusetion. So would the rear off the car squatting help with traction when putting the power down?

The harder the rear the more chance of oversteer, the harder the front the higher chance of understeer (in relation to one another)

Droop on the rear under hard acceleration helps weight transfer, but it also damps the initial snatch of the power coming on during launch or hard gear changes, which in turn gives the rear tyres a chance to bite.

Holy thread revival Batman!!!
A quick question for Jon, I based my suspension off of what you've detailed in this thread, So I went for H&R progressive front springs, no exact figures but people suggest around 180-220 lbs I hhave aspring spacer of 19mm so I believe I've lowered around 10-15mm at the front, I'm keeping the stock roll bars (26.8mm hollow fronts, 16mm solid rears) for the moment until funds allow, I have Bilstein B6 all round, I have 26mm torsion bars at the rear, indexed to match the fronts ride height
Which leads me on to my question, For a general road car with the occasional trackday, would you stick with the stoch wheel allignments or would you go for a more track orientated setup.
I hope all is well with you.
Cheers
Steve
944S2 Cab
Sydney
Australia