RonD.

Front Koni single adjustable with 450 lb. springs Rear Koni sport Adjustable shocks. Best setting for rears to match up with fronts? Full stiff?

968to986

Those are heavy front springs. Do you know what size torsion bars are at the rear, or coilover conversion? I think you want to know that to make decisions about shock adjustment. Also, what’s the intention for the car? Track, autocross or street?

RonD.

Rear torsion bars are original stock 87 951which came with 474 Sport Susp. from factory. That set was completely shot so on a budget I picked up the set of used front struts with springs already assembled along with the rears shocks, not coilover . Both Koni single adjustable. They were to good a deal to pass up $400.00 shipped. they were supposedly used on a Lemons car for one race. They are painted black with yellow showing and part numbers are legit. I think they were painted so they would pass inspection and meet race regs.

I realize the springs are a bit heavy for primarily street driving with a handful of track days. I'm simply trying to adjust the rears (full stiff??) to match with the fronts as close as I can, if at all, without going to rear coilovers. If bigger torsion bars would help? I could probably try that.

beamishnz

You are getting confused with shock absorber adjustment and spring rate. You cannot balance 450lb front springs by adjusting the rear shock absorber settings.

450lb fronts are fairly heavy springs for road use but not impossible if you don't mind a very firm ride and the roads in your area are in relatively good condition. But you will definitely need an effective rear spring rate to match the front or you will have a horribly handling car particularly under heavy braking. You options are to supplement the current torsion bars with 200-250lb coilover springs or change existing torsion bars for 30 - 31mm bars.

Hope this helps.

kev951

You need softer springs 250 lb. 400 lb springs and up need much larger torsion bars. So unless you're planning on swapping 30 mm torsion bars in there all you are going to do is understeer

RonD.

Thanks for the input everyone.Short of doing whats really necessary. I'm just asking if adjusting current rear shocks either way will help in anyway with handling?

968to986

I don’t think you’ll get much benefit from adjusting the rears to full, but give it a shot! I’m running 250# front springs with single adjustable Konis and 28mm torsion bars with Konis. Between autocrosses a few weeks ago, I adjusted my fronts from medium to full hard to try to improve the transient response in slaloms. I thought, maybe, I felt a difference. For the next autocross I plan to adjust the rears to full hard, because why not?

Is there a way to add helper springs to your rear shocks to work with the torsion bars? Or just buy huge torsion bars and experience the unique pleasure of installing and indexing bars on a 944.

MAGK944

With 450lb springs up front and stock rear torsion bars it’s going to understeer like a pig regardless how stiff you set the rear dampers.

Like everyone is saying, you need to lower the front spring rates to around 200-220 then turn your dampers at the rear full stiff and you should be good.

333pg333

Yet stock springs and setup allows for a ton of roll. Perhaps look to updating the whole system if you can afford to make a wholesale change. If not, yes, need to go back lower spring rate on fronts.

zmf

I've got 450 lbs in front, and with stock sway bar and coil-overs, 350 lb in the rear. Shocks are set the same all around, with a slight front tire pressure bias.
Yes, you might think there'd be understeer, but it depends on your driving style. I tend to drive hard into a corner, trail brake, and sling the rear end around. The trick is be on the edge of oversteer under those conditions.

I agree that 450 up front and stock rear would make it hard to rotate a 944.

Are we talking street or track?

RonD.

Pretty much street with maybe a couple SCCA Track Nights at Pocono. I've been looking for advice on what I can do to the rear without messing with the front. If I was going to DE a lot I would invest in best springs for the front to match the rear Koni's or upgrade the rear with what's best to go with the front and of course I know changing out the front springs would be simplest and cheapest way to go. I've had that set-up on a different 951 and it played well on the track.

zmf

I can't add to the advice you've gotten. Seems you have the front suspension of a track car, and a stock rear suspension. There's got to be a front/rear compromise -- more in the rear or less in the front.

Flea3

Don’t due that. 450 front is 409 effective with 126 effective stock rear. That’s a 3.57 ratio. That is terrible. It’s supposed to be closer to 1.0. That car will understeer right into a tree on a turn. For comparison, stock is .92. KW’s (which are understeer prone) are 1.26. The general rule is over 250 you have to adjust the rear somehow. Even with 250, it still will favor understeer but at least it won't kill anyone.

RonD.

Confirmed front springs are actually Weltmeister progressive rate 250 lb 1" lowering, not 450lb. So for now I'm planning on bigger rear sway bar? and Koni Sports on full stiff in the rear.

mj951

The 19mm adjustable M030 rear sway bar is a nice upgrade.
The original Porsche version has three settings (holes). Lindsey Racing makes a similar bar with five.
I have the original M030 and you can definitely feel the difference in balance between settings. Of course it's relative to the rest of your setup but can help balance a car front to rear.

I would set the car neutral and take it to the track. Get a few laps in and make one change at a time to understand the changes. Neutral to full soft to full stiff, what do those settings offer at various parts of the track, keep good notes.
It's all a compromise with lots of variables. In addition to alignment settings there's, air temp., track temp, tire temp (inside/middle/outside), tire pressure (cold/hot), shock settings (front/rear) sway bar settings (front/rear)...and of course driver skill to be putting down consistent laps.