M030 springs on M474 S2 struts ?
10-28-2003, 02:52 PM
#16
Originally posted by Skip
I used the numbers you gave and converted them - that's not from a book, so I hope you were right.
Did you understand what I said... Sprechen Sie Deutsches?!?
I used the numbers you gave and converted them - that's not from a book, so I hope you were right.
Did you understand what I said... Sprechen Sie Deutsches?!?
11-01-2003, 09:33 AM
#18
'Sport' springs were an option on US 968's. I remember reading somewhere that H&R made these for Porsche. I have the H&R progressive sport springs from Paragon, and I'm guessing these are what came on the CS.
11-22-2003, 02:38 PM
#19
Skip mentioned above that 968 and S2 have the same spring diameter but he did not specifically reckon anything re 968 CS springs (which I understand as 968 CS did not make it in the US market), so I eventually took the plunge and bought a set of non M030 968 CS springs.
To my great sastisfaction, the diameter is exactly the same as S2's, but (there's always a but) they approximately measure 330 mm - or 324 mm according to the WM (many thanks again to PorscheG96 for the info).
I will (intend to) fit these tomorrow morning, but I'm still wondering if they will fit fine, since :
1) Base suspension S2 springs measure 378 mm. That's what I have on the car right now.
2) I have M474 S2 struts. The WM indicates that M474 S2 springs are 11 mm shorter than base S2 springs. Now, assuming that S2 with M474 have the same ride height as S2 with base suspension, my car would currently be 11 mm to high, which seems plausible when looking at this.
3) 378 - 324 = 54 mm / 2.1" : it seems to me that getting the car 2.1" lower is a bit too extreme for the security of the front fenders. Now, assuming 2) is correct, this reduces to 54 - 11 = 43 mm / 1.7", which still seems a bit too much.
What do you guys think ? Do you think the tires will come in contact of the fenders ?
I would really appreciate some opinions on this before tomorrow morning (it's 19h38 here, by the way
).
Thanks in advance.
To my great sastisfaction, the diameter is exactly the same as S2's, but (there's always a but) they approximately measure 330 mm - or 324 mm according to the WM (many thanks again to PorscheG96 for the info).
I will (intend to) fit these tomorrow morning, but I'm still wondering if they will fit fine, since :
1) Base suspension S2 springs measure 378 mm. That's what I have on the car right now.
2) I have M474 S2 struts. The WM indicates that M474 S2 springs are 11 mm shorter than base S2 springs. Now, assuming that S2 with M474 have the same ride height as S2 with base suspension, my car would currently be 11 mm to high, which seems plausible when looking at this.
3) 378 - 324 = 54 mm / 2.1" : it seems to me that getting the car 2.1" lower is a bit too extreme for the security of the front fenders. Now, assuming 2) is correct, this reduces to 54 - 11 = 43 mm / 1.7", which still seems a bit too much.
What do you guys think ? Do you think the tires will come in contact of the fenders ?
I would really appreciate some opinions on this before tomorrow morning (it's 19h38 here, by the way
).Thanks in advance.
11-22-2003, 04:10 PM
#20
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Thom-
I might be mistaken, but I think that the spring length you are quoting is the "free" or uncompressed length. Depending on the spring rate, the final ride height of the car could be the same even if the free length of the springs is different. I know this does not answer your question, but if you know the spring rates of the ones you have, you could make a pretty good estimation of how much drop you will experience.
Also as far as the wheels contacting the fenders, I doubt any Porsche leaves the factory with springs that are not capable of keeping the car off the bump stops on the street in all but the most severe instances. A drop in ride height should come with an accompanying increase in spring rate to make up for the lost travel.
Good luck,
I might be mistaken, but I think that the spring length you are quoting is the "free" or uncompressed length. Depending on the spring rate, the final ride height of the car could be the same even if the free length of the springs is different. I know this does not answer your question, but if you know the spring rates of the ones you have, you could make a pretty good estimation of how much drop you will experience.
Also as far as the wheels contacting the fenders, I doubt any Porsche leaves the factory with springs that are not capable of keeping the car off the bump stops on the street in all but the most severe instances. A drop in ride height should come with an accompanying increase in spring rate to make up for the lost travel.
Good luck,
11-22-2003, 05:19 PM
#21
Riff - you are absolutely right.
Base CS springs : K1 = 28 N/mm ; L1 = 324 mm
Base S2 springs : K2 = 23.8 N/mm ; L2 = 378 mm
Weight remains unchanged means K1 x (L1 - X1) = K2 x (L2 - X2), where |X2 - X1| is the actual difference in ride height.
|X2 - X1| = |K2/K1 x L2 - L1 + (1 - K2/K1) x X2|
X2 is my base S2 spring length while compressed - I don't know the value ...
Base CS springs : K1 = 28 N/mm ; L1 = 324 mm
Base S2 springs : K2 = 23.8 N/mm ; L2 = 378 mm
Weight remains unchanged means K1 x (L1 - X1) = K2 x (L2 - X2), where |X2 - X1| is the actual difference in ride height.
|X2 - X1| = |K2/K1 x L2 - L1 + (1 - K2/K1) x X2|
X2 is my base S2 spring length while compressed - I don't know the value ...
Last edited by Thom; 11-23-2003 at 03:01 AM.
04-30-2004, 09:03 PM
#23
Skip wrote:
quick guide to swappable spring fitments:
group 1 - 83-89 944, 86-88 951, 87-88 944S, 924S
group 2 - 89-91 944S2, 968
group 3 - 88-89 951S, 944S2 w/M030, 968 w/M030
And their aftermarket options:
group 1 - Weltmeister or Eibach 200, 220, 250, 260 sport springs (lowers ~1.25", can be used with spacer to lift 1")
group 2 - H&R lowering springs (lowers ~1.25")
group 3 - 2.5" ID racing spring available in any rate, must also add adapter parts for changed spring diameter.
Are you indicating that you can swap springs in the groups as long as they have the same number of dots? Or could I use spring that have one (1) yellow dot in place of the three (3) blue dots.
The front of the car dives way too much during heavy braking during racing and autocross.
Michael
quick guide to swappable spring fitments:
group 1 - 83-89 944, 86-88 951, 87-88 944S, 924S
group 2 - 89-91 944S2, 968
group 3 - 88-89 951S, 944S2 w/M030, 968 w/M030
And their aftermarket options:
group 1 - Weltmeister or Eibach 200, 220, 250, 260 sport springs (lowers ~1.25", can be used with spacer to lift 1")
group 2 - H&R lowering springs (lowers ~1.25")
group 3 - 2.5" ID racing spring available in any rate, must also add adapter parts for changed spring diameter.
Are you indicating that you can swap springs in the groups as long as they have the same number of dots? Or could I use spring that have one (1) yellow dot in place of the three (3) blue dots.
The front of the car dives way too much during heavy braking during racing and autocross.
Michael
