Tire size question...
#1
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The 993 is currently running 205's in the front.
The car seems to understeer far to much....
Anyone know if you can run 225's front and what diffrence it make's?
The car seems to understeer far to much....
Anyone know if you can run 225's front and what diffrence it make's?
#2
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You can run 225s without any rubbing. 17" wheel right?
Check out my tire size calculator:
Tirecalc.html
A 225/45-17 is about 0.4% smaller than a 205/50-17.
My preferred method of reducing understeer is PSS-9s and RS swaybars, front bar full soft, rear bar in the middle.
Check out my tire size calculator:
Tirecalc.html
A 225/45-17 is about 0.4% smaller than a 205/50-17.
My preferred method of reducing understeer is PSS-9s and RS swaybars, front bar full soft, rear bar in the middle.
#4
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Fishey,
I'm about to go to MPSC's in a 225/18 front and 265/18 rear with Fikse FM-10's (correct offset, of course.) I was told I shouldn't have any rubbing problems, even with my very lowered and PSS-9-equipped car. I actually would like to go to a 235 in front but Michelin doesn't make that size.
I'm about to go to MPSC's in a 225/18 front and 265/18 rear with Fikse FM-10's (correct offset, of course.) I was told I shouldn't have any rubbing problems, even with my very lowered and PSS-9-equipped car. I actually would like to go to a 235 in front but Michelin doesn't make that size.
#5
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I went with 225s in front, looked at the tire size calc, etc. For my tires (RE 750s) the 225s were actually a better overall diameter match to the 255 rears, so I was pretty happy, and the understeer is actually quite significantly less in Auto X...I have only 1 track day so can't speak to that, and on the street, well, who knows...I wore the last set down to about nothing, so hard to say the improvement is from size or just new tires.
I really stressed over how it would look and all that...you really can't tell the difference visually, and the little bit you can I think actually fills up the well a bit better.
I really stressed over how it would look and all that...you really can't tell the difference visually, and the little bit you can I think actually fills up the well a bit better.
#7
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Fishey
I've run 225x17 MXX3 fronts on stock 7" Cups this DE season. My car is mildly lowered. Very noticeable decrease in understeer & no rubbing. Many here have used that size for years. There's no reason I can think of not to use 225.
I've run 225x17 MXX3 fronts on stock 7" Cups this DE season. My car is mildly lowered. Very noticeable decrease in understeer & no rubbing. Many here have used that size for years. There's no reason I can think of not to use 225.
Last edited by Dan 96C2 St.Louis; 09-25-2003 at 04:48 PM.
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#8
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stock rim's for a 1995 c2 (the 17" cups)
(I think there 7" on front right?)
Also I head on the 995 there is something you need to do to mount 18" rims..... What would this be?
(I think there 7" on front right?)
Also I head on the 995 there is something you need to do to mount 18" rims..... What would this be?
#10
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I guess? I don't really know.....
I remember hearing something about a modification you need to do to 1995's to mount 18's... I dont understand the need for the brace? maybe you can help me understand.
I remember hearing something about a modification you need to do to 1995's to mount 18's... I dont understand the need for the brace? maybe you can help me understand.
#11
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Fishey,
There are a bunch of threads on it. Try this link.
As per some Porsche service bulletin, some 993's with certain VIN's require it while others don't. I was told that even if you don't have it, you should install it if you're running 17" or 18" wheels on the track. I just bought one at Crescent Porsche (800-966-7222) for about $34, not including shipping or the screws.
Part # for steering rack brace: 993-347-131-02
Part # for screws (2 needed): 999-218-103-09
There are a bunch of threads on it. Try this link.
As per some Porsche service bulletin, some 993's with certain VIN's require it while others don't. I was told that even if you don't have it, you should install it if you're running 17" or 18" wheels on the track. I just bought one at Crescent Porsche (800-966-7222) for about $34, not including shipping or the screws.
Part # for steering rack brace: 993-347-131-02
Part # for screws (2 needed): 999-218-103-09
Last edited by Mark in Baltimore; 09-25-2003 at 07:14 PM.
#12
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Originally posted by Fishey
stock rim's for a 1995 c2 (the 17" cups)
(I think there 7" on front right?)
stock rim's for a 1995 c2 (the 17" cups)
(I think there 7" on front right?)
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Originally posted by Silver Bullet
Mark - I've been told by Michelin that 235x40 will be out later this year
Mark - I've been told by Michelin that 235x40 will be out later this year
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Originally posted by Matt Vaughan
Hey Kim, any idea what the overall diameter will be? IOW, a good match for our 285/30's?
Hey Kim, any idea what the overall diameter will be? IOW, a good match for our 285/30's?
285-30-18: 24.7"
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Originally posted by Viken
235-40-18: 25.4"
285-30-18: 24.7"
235-40-18: 25.4"
285-30-18: 24.7"
Viken, where'd you get your specs?