Wheel Spacer Advice
11-17-2014, 09:01 PM
#1
Racer
Thread Starter
Wheel Spacer Advice
I have a 2009 C2S with the stock 19" Carrera S II wheels. I have searched this forum and didn't find the information I am looking for regarding wheel spacers. Aside from the cosmetic benefits of making the car more aggressive looking, are there any advantages to adding spacers? Are there any risks or concerns that I should be aware of if I added spacers?
Any insight would be appreciated and thank you in advance.
Any insight would be appreciated and thank you in advance.
11-22-2014, 09:50 AM
#2
Former Vendor
It's primarily for looks, or to make a non standard set of wheels (ie putting 911 wheels on a 944) fit correctly. There's no real performance advantage IMO to using spacers, some guys just like that more aggressive look. The biggest technical issue would be to make sure 5 and 7mm spacers are properly centered as they are flat and don't have the step milled into them to for the wheel hub to accept. 15mm and higher have the step. I have 7, 15, and 18 for 993+ if you need them 
11-24-2014, 09:39 PM
#3
The only performance advantage is widening the effective track width - width between the center of each tire's contact patch.
Performance disadvatages: More unsprung weight. Path of dirt flinging is closer to bodywork. Depending on spacer, tires could start to rub.
Other disadvatages: If you get adapters, that means you have lug bolts you cannot regularly check. Some organizations do not allow adapters in DE or club track events.
Performance disadvatages: More unsprung weight. Path of dirt flinging is closer to bodywork. Depending on spacer, tires could start to rub.
Other disadvatages: If you get adapters, that means you have lug bolts you cannot regularly check. Some organizations do not allow adapters in DE or club track events.
12-27-2014, 09:15 PM
#4
Rennlist Member
The entire suspension, including the wheels, is a design system build to accomplish a mission. It is a balancing act of grip and suspension travel organized to control kinetic energy in the turns.
Too much spring can reduce travel which transfers the kinetic energy to another component. Too much tire can create too much grip and slow the car down in terms of acceleration and aerodynamics, and overload the other suspension parts.
The 993 came with 16" rims, with 17"s as the option. I found the 17s good for the track but the 16s much better on the street, even in aggressive driving. The 996 came with 17"s as standard and 18's as the option. I'm staying with my 17s for the same reason as with the 16s on the 993. The 996 also has between 25 to 50 more hp...and is lighter than the 993 so it can make better use of the 17s vs the 993 16s.
By widening the tracks with spacers you are extending the suspension outward, like increasing the span of a bridge. Under normal driving it may not present a problem...but under extreme situations the weakest points in the bridge's span can begin to fail. In this case I'm guessing ball joints, wheel bearings, steering rack.
One of the lessons in vintage racing is how modern tires can overload vintage suspensions. I had to have re-enforcements welded onto where the chassis and suspension met on my '58 vintage Alfa racer. Those that did not make those changes often found the suspension being literally pulled from the frame.
When the VW GTIs first came out, it was US dealers who started putting on oversized tires. In Europe they laughed at the cosmetic game and stayed with the tires the suspension was designed for. And they were faster as a result.
Too much spring can reduce travel which transfers the kinetic energy to another component. Too much tire can create too much grip and slow the car down in terms of acceleration and aerodynamics, and overload the other suspension parts.
The 993 came with 16" rims, with 17"s as the option. I found the 17s good for the track but the 16s much better on the street, even in aggressive driving. The 996 came with 17"s as standard and 18's as the option. I'm staying with my 17s for the same reason as with the 16s on the 993. The 996 also has between 25 to 50 more hp...and is lighter than the 993 so it can make better use of the 17s vs the 993 16s.
By widening the tracks with spacers you are extending the suspension outward, like increasing the span of a bridge. Under normal driving it may not present a problem...but under extreme situations the weakest points in the bridge's span can begin to fail. In this case I'm guessing ball joints, wheel bearings, steering rack.
One of the lessons in vintage racing is how modern tires can overload vintage suspensions. I had to have re-enforcements welded onto where the chassis and suspension met on my '58 vintage Alfa racer. Those that did not make those changes often found the suspension being literally pulled from the frame.
When the VW GTIs first came out, it was US dealers who started putting on oversized tires. In Europe they laughed at the cosmetic game and stayed with the tires the suspension was designed for. And they were faster as a result.