utkinpol

Rad always says for 600/900 while rest of the world does 700/900 and i always wondered why is that so.
shop i use does not agree with such split at all, he says it is all inherited from 993 cars and 997 cars do not benefit from such big split at all. go figure.

Orbit r

KW is one the best suspension manufactures out there. The best teams in the world run them, and we have great success running KWs on our race cars.
People usually compare apples to oranges, as the majority either don't know or don't have access to their motorsports products.

NJ-GT

Simply, tell your shop and the rest of the world to measure front and rear motion ratio, then tell them to calculate wheel rates, then tell them to read corner weights, then tell them to remove a front and a rear suspension and put it on the scales with wheel/tire weight, then subtract from corner weights, then determine spring rates for the intended frequency.

Bone stock 997.2 GT3 RS (250/600)
Bone stock 996 GT3 (225/550)
Ohlins (700/1300)
Manthey and KW (big split)

Wheel sizes, tires, sway bars then are added into the mix, once you have the baseline.

For instance, my Cayman is running a 550/650 split, because I run the same size front and rear tires (285 at all corners), so I need even more springs on the front axle, and I add even more springs to increase torsional rigidity on the front compared to the rear, to eliminate inside wheel spin (my Coxster doesn't have a diff).

Larry Cable

I recall running a 200 difference between F/R on the 964 and 993 ... seemed to work out ... I can imagine that the 6's and 7's may not benefit from such ...

its all science and art ... beyond me if not most of us...

NJ-GT

the 996 GT3 measured ideal split is 600/800, but you can play stiffer/softer depending on tires, and different splits depending on wheel sizes, tire sizes, custom sway bars, weight distribution, Aero, etc.

utkinpol

i found an old note from my builder -

>As I recall I had mentioned we have never set up a 996/7 with a 200lb rate diff.... always have gone 100

i do not have an opinion on those matters due to lack of understanding.

would be interesting to get a car on 800/900 springs and run it against car on 600/900 springs just to see how will it work out.

as i can understand - as you get more aero in front and increase your entrance speed to the max you do need more rigidity on front axle to maintain grip mid-corner, therefore are advices to stiffen up front sway bar and etc. it contradicts with lower speed max grip on corner entrance so that is probably why street cars have soft front springs and race cars have exact opposite but honestly i do not know what to think. i also have heard that TPC sets up race cars with 900/900 springs and also puts in custom very thick front sway bar to stiffen it even more to allow driver (as i understand) to go flat out through the whole corner. or may be i am wrong. i wish somebody could explain all that in simple enough terms an average mechanical engineer could understand.

Veloce Raptor

Yup. Now I know why I said KW: I had another client with a 996 GT3 running KW's, at VIR last year. Absoluutely fantastic, fantastic suspension!!

NJ-GT

Sachs, Penske and Ohlins !!!

mdrums

Way to expensive...except for you Fiat guys. I bet if Randy or Peter ever put on some coil overs like these you'd never leave them alone...LOL