What do you think on rim size?
05-19-2009, 05:07 PM
#1
Rennlist Member
Thread Starter
What do you think on rim size?
Hi guys,
This weekend I attended the Porsche Sport Driving School in Baden-Baden, Germany.
It was a truly great event, which I can highly recommend if you want to get to know your car better, hone your driving skills and meet a bunch of nice, Porsche-loving people.
During the course, I realised that my C4 understeers a lot when cornering at speed, something I have decided to fix.
I currently have Bridgestone S02-A tires on the car; 205/50 ZR 17 in front, and 255/40 ZR 17 in the back.
The rims are OEM Cup II: 7 ET 55 front and 9 ET 70 rear.
The car has the M050 sports suspension from the factory, and I installed HR springs, Bilstein shocks and a strut brace last year.
On my old 964 C4 it made a huge improvement to it’s understeering, when I fitted 225 17" tires in the front, and 255 17" in the back.
Does any of you have experience with the effect of fitting wider tires in the front of your 993?
I want to keep the rims OEM, so can I fit 225 tires to a 7” rim, or do I need to buy new rims for the front?
Will it do the trick run with 225 front and 255 rear? Or do I need to fit wider tires in the rear as well? (265?)
Your advice is much appreciated!
And, yes, I will post photos from the event as soon as finish I re-sizing the images
Take care,
This weekend I attended the Porsche Sport Driving School in Baden-Baden, Germany.
It was a truly great event, which I can highly recommend if you want to get to know your car better, hone your driving skills and meet a bunch of nice, Porsche-loving people.
During the course, I realised that my C4 understeers a lot when cornering at speed, something I have decided to fix.
I currently have Bridgestone S02-A tires on the car; 205/50 ZR 17 in front, and 255/40 ZR 17 in the back.
The rims are OEM Cup II: 7 ET 55 front and 9 ET 70 rear.
The car has the M050 sports suspension from the factory, and I installed HR springs, Bilstein shocks and a strut brace last year.
On my old 964 C4 it made a huge improvement to it’s understeering, when I fitted 225 17" tires in the front, and 255 17" in the back.
Does any of you have experience with the effect of fitting wider tires in the front of your 993?
I want to keep the rims OEM, so can I fit 225 tires to a 7” rim, or do I need to buy new rims for the front?
Will it do the trick run with 225 front and 255 rear? Or do I need to fit wider tires in the rear as well? (265?)
Your advice is much appreciated!
And, yes, I will post photos from the event as soon as finish I re-sizing the images
Take care,
Last edited by jenskleis; 05-19-2009 at 05:47 PM.
05-19-2009, 05:33 PM
#2
if your car is oversteering then you want to increase rear grip,
you do that by
higher front spring rate
lower rear spring rate
stiffer front sway
softer rear sway
harder front shock setting
softer rear shock setting
less neg front camber
more neg rear camber
smaller front tire
larger rear tire
lower front air pressure
higher rear air pressure
less front spoiler
more rear spoiler
you do that by
higher front spring rate
lower rear spring rate
stiffer front sway
softer rear sway
harder front shock setting
softer rear shock setting
less neg front camber
more neg rear camber
smaller front tire
larger rear tire
lower front air pressure
higher rear air pressure
less front spoiler
more rear spoiler
05-19-2009, 05:52 PM
#4
06-08-2009, 09:48 PM
#5
225's on C4
I'm running 225/45's up front PS2's and 255/40's out back, complete stock suspension and she sticks pretty good.
Hi guys,
This weekend I attended the Porsche Sport Driving School in Baden-Baden, Germany.
It was a truly great event, which I can highly recommend if you want to get to know your car better, hone your driving skills and meet a bunch of nice, Porsche-loving people.
During the course, I realised that my C4 understeers a lot when cornering at speed, something I have decided to fix.
I currently have Bridgestone S02-A tires on the car; 205/50 ZR 17 in front, and 255/40 ZR 17 in the back.
The rims are OEM Cup II: 7 ET 55 front and 9 ET 70 rear.
The car has the M050 sports suspension from the factory, and I installed HR springs, Bilstein shocks and a strut brace last year.
On my old 964 C4 it made a huge improvement to it’s understeering, when I fitted 225 17" tires in the front, and 255 17" in the back.
Does any of you have experience with the effect of fitting wider tires in the front of your 993?
I want to keep the rims OEM, so can I fit 225 tires to a 7” rim, or do I need to buy new rims for the front?
Will it do the trick run with 225 front and 255 rear? Or do I need to fit wider tires in the rear as well? (265?)
Your advice is much appreciated!
And, yes, I will post photos from the event as soon as finish I re-sizing the images
Take care,
This weekend I attended the Porsche Sport Driving School in Baden-Baden, Germany.
It was a truly great event, which I can highly recommend if you want to get to know your car better, hone your driving skills and meet a bunch of nice, Porsche-loving people.
During the course, I realised that my C4 understeers a lot when cornering at speed, something I have decided to fix.
I currently have Bridgestone S02-A tires on the car; 205/50 ZR 17 in front, and 255/40 ZR 17 in the back.
The rims are OEM Cup II: 7 ET 55 front and 9 ET 70 rear.
The car has the M050 sports suspension from the factory, and I installed HR springs, Bilstein shocks and a strut brace last year.
On my old 964 C4 it made a huge improvement to it’s understeering, when I fitted 225 17" tires in the front, and 255 17" in the back.
Does any of you have experience with the effect of fitting wider tires in the front of your 993?
I want to keep the rims OEM, so can I fit 225 tires to a 7” rim, or do I need to buy new rims for the front?
Will it do the trick run with 225 front and 255 rear? Or do I need to fit wider tires in the rear as well? (265?)
Your advice is much appreciated!
And, yes, I will post photos from the event as soon as finish I re-sizing the images
Take care,
