troppo

I just realized my set of springs is not all row m030 but fronts are m030 and rears are turbo. My car is going in tommorrow...will this setup work or should I call it off and order the correct spring set?? btw, I have a 98 c4s


thanks-

troppo

anyone on this...?

David in LA

Get the correct springs. Mismatched springs can be dangerous as the handling will be adversely affected. Plus your car will look funny unless the Turbo's are also ROW.

geolab

There is no such thing as M030 fronts and turbo fronts.
M030 springs in front are the same for TURBO, or in other words, Turbo has m030 springs in the front.
Orange color on the spring for USA
Orange green for he ROW

The springs in the rear differ a lot. The difference in springs is for ride height, stiffness, but mainly for weight compensation.

Carrera 4S rear in ROW rear spring color code is pink
M030 is brown
Turbo is red

Carrera 4S rear US is either gold yellow,
or light blue with the m030 option
turbo is yellow green.

Garth S

Geolab,
I think Toppo meant the ROW Turbo set vs. the ROW M030 set: the fronts of both are identical (orange/green/green) as you noted .... but the latter rears are coded red/red/red. The heights should be similar, so what is the effect of a higher rear ( turbo) spring rate on a non-turbo 993? .... I think that is his question ( and I have no answer).

BTW - the 'stock' C4S rears from my US spec car are 3 green stripes: they appeared to be the original springs - but remain a mystery.

DJF1

It should not be a disaster. Porsche kept the stock spring rates to about 100lbs difference between the front and the rear ( stiffer rear). Worse case scenario if the Turbo springs are stiffer than the M030 is that it widens the gap by a few pounds maybe to 150lbs. By comparison I run a 200lbs spring difference in my race car and this is considered the norm. On the Factory RS the spring difference between front and rear is about 200lbs too.
So it should not be a disaster, if anything else it will shave off some of the inherit understeer due to a stiffer rear. If the springs are a bit softer then it will add some understeer, but I dont think that is the case.
At any rate I dont think its a disaster, if we are only talking about spring rates. If there is a ride height isssue by the rear springs been longer than the front then I'm afraid you need the correct springs as this difference will have an adverse impact on the proper rake and corner balance of the car.

One last thing, I just noticed you are in Colorado. You have probably one of the best mechanics for setup in the world at your door step. If you dont know Chris Cervelli , then look him up and take your car to him. For sure you will have a very sweet setup from him.

geolab

The difference between non-turbo springs and turbo ones is that the latter are manufactured to behold 85 kilos more on the rear axle alone.

So if mounted on a normal carrera, it will have a very stiff ride, great for track (totally agreeing with DJF1), but catastrophic for irregular road.

Strange enough, the carrera 4S in the US was sold with m030 and some without.
The only green green springs from porsche are for front normal carrera (US or ROW)
part number 96434353111 504
rear normal carrera US is white green 99333353108 504
rear turbo US is yellow green 99333353117 504
Front turbo ROW is orange green 96534353101 504

thats all the green there is
thanks Garth

Martin S.

I have the data...I actually measured the 993TT rear springs. Here is a summary of what I found. If you want specifics, send me an e-mail and I will send you the EXCEL spread sheet..

As we knew, the 993TT is delivered with M030 (US) springs. They have the M030 (US) markings. On the set of front and rear springs I measured, the rears are actually taller than the M030 (US). This may be to compensate for the nearly 300 Lbs. extra weight or the 993TT over the NA cars...and the rearward bias on this weight.

troppo

Martin-pm sent