19 inch wheels on a 996

[Loren]

Looks like the fronts will work but not the rears.

You would need a rear offset of 63 to 65 mm.

[Serg]

I was hoping that since the rear wheels were 9.5 in., that the narrower rim might make up the difference and not have the tire rub on the fender.

[balefire]

Not to hijack the thread ... but: I have a chance to purchase a set of wheels 18x7.5 and 18 x 9.5 respectively for almost nothing. I was thinking about using them as a secondary set for winter, etc....

I have 18x8 and 18x10 mounted on my 99 996 cab at the moment. Is the .5 in diff going to have a significant effect?

Hi Loren,

The offsets are 50 and 54 respectively.

Serg

I was hoping that since the rear wheels were 9.5 in., that the narrower rim might make up the difference and not have the tire rub on the fender.

Serg,

The wheels will fit your car. They may be a good winter set since they are narrow, but would not make an ideal summer set since stock tires may have tire squirm on that narrower wheel.

[rallygabe]

I also bought a 99 c2 that had 19s on it. Ride was horse****, IMHO. Looked stunning!

Anybody want a set of 997 turbo/carreraS 19s? 8.5/11 widths! :)

[williampeyton]

UPDATE: I found out that if you own a 996 you have to get the suspension tuned to handle 19" tires. On my previous post I mentioned that I did not know if my suspension was tweaked or not, I found out that it was. It was tweaked to handle 19"/295 tires. I have no rub in the inside of my wheel well and it does not hit my suspension or make contact when I go over bumps or corner really hard duing autocrossing. In fact I took off my rims for winter ( where I am they put salt on the roads) and put on 18"/255. The ride is the same, however 2 things happened. One, for the first mile my PSM would kick in everytime I turned left or right I guess the computer had to re learn the smaller tires. The second thing that has happened is now my car reads me going faster than what I really am, it shows I am going 4mph faster than my actually speed. Which was backed up by a certified radar. When I acquired about the speedometer being off 4 mph as soon as I change the tires and a look at my suspension. I was told my suspension was tuned to handle the tires it was orginally riding on and along with my ECU. The meat of this story is, you can use 19" or 20" tires but you will have to get the suspension tuned to handle the extra size. The 996's originally came with 17' tires, with the option of 18" and the 997's come orginally with 18" and the option of 19".

[balefire]

UPDATE: I found out that if you own a 996 you have to get the suspension tuned to handle 19" tires. On my previous post I mentioned that I did not know if my suspension was tweaked or not, I found out that it was. It was tweaked to handle 19"/295 tires. I have no rub in the inside of my wheel well and it does not hit my suspension or make contact when I go over bumps or corner really hard duing autocrossing. In fact I took off my rims for winter ( where I am they put salt on the roads) and put on 18"/255. The ride is the same, however 2 things happened. One, for the first mile my PSM would kick in everytime I turned left or right I guess the computer had to re learn the smaller tires. The second thing that has happened is now my car reads me going faster than what I really am, it shows I am going 4mph faster than my actually speed. Which was backed up by a certified radar. When I acquired about the speedometer being off 4 mph as soon as I change the tires and a look at my suspension. I was told my suspension was tuned to handle the tires it was orginally riding on and along with my ECU. The meat of this story is, you can use 19" or 20" tires but you will have to get the suspension tuned to handle the extra size. The 996's originally came with 17' tires, with the option of 18" and the 997's come orginally with 18" and the option of 19".

Your source is wrong.Wheel diameter can be changed independent of suspension or alignment provided the fitmentis correct.Your 255 width is incorrect and would undoubtedly cause speedometers errors and psm errors.

[DiscobayJoe]

I run 19's.   Just went to 305/30/19's RE11's in the Rear and it understeers like mad with 225's in the front.    Switching To 245/35/19 in the front this weekend! 

 

Here's my old setup with 225/35/19 & 285/35/19

 

[Loren]

I run 19's.   Just went to 305/30/19's RE11's in the Rear and it understeers like mad with 225's in the front.    Switching To 245/35/19 in the front this weekend! 

 

Here's my old setup with 225/35/19 & 285/35/19

 

 

Those fronts will rub - pretty much guaranteed.

[DiscobayJoe]

What Do you feel is the biggest tire I can wedge in the front of an otherwise stock C2?     I don't rub at all with 225/35/19's.    I think they are 8.5's. 

[Loren]

What Do you feel is the biggest tire I can wedge in the front of an otherwise stock C2?     I don't rub at all with 225/35/19's.    I think they are 8.5's. 

 

Most 240's will rub slightly at full lock... depending on your wheel manufacturer and tire.

It's a tough call with a taller wheel - you might have to experiment.

 

I run a 235/40 on an 8 inch x 18 inch wheel and it just barely clears.

[DiscobayJoe]

Where would it be rubbing?   Inner Fender Wall to the rear edge of the tire or outer fender on the front edge?

[Loren]

Shock/strut perhaps also on bump rebound.

[j_beede]

FYI: My 997.1 has 20" OZ Ultraleggera all the way around. I have yet to figure out how to measure the wheel width or offset. 295/30 in the back, 245/30 in front. 1" drop via TechArt spring kit. Looks great. Rides great. Slot car cornering. No rub. Speedo and GPS report identical MPH. I couldn't imagine going back to 18". Only regret is limited tire choice and how hard it is to clean these monster wheels!

[Loren]

FYI: My 997.1 has 20" OZ Ultraleggera all the way around. I have yet to figure out how to measure the wheel width or offset. 295/30 in the back, 245/30 in front. 1" drop via TechArt spring kit. Looks great. Rides great. Slot car cornering. No rub. Speedo and GPS report identical MPH. I couldn't imagine going back to 18". Only regret is limited tire choice and how hard it is to clean these monster wheels!

 

What is your front wheel width and offset?

[j_beede]

 

FYI: My 997.1 has 20" OZ Ultraleggera all the way around. I have yet to figure out how to measure the wheel width or offset. 295/30 in the back, 245/30 in front. 1" drop via TechArt spring kit. Looks great. Rides great. Slot car cornering. No rub. Speedo and GPS report identical MPH. I couldn't imagine going back to 18". Only regret is limited tire choice and how hard it is to clean these monster wheels!

 

What is your front wheel width and offset?

 

 

It looks like the poster noted that he doesn't know the width and offset of his wheels.

[RymerC]

What Do you feel is the biggest tire I can wedge in the front of an otherwise stock C2?     I don't rub at all with 225/35/19's.    I think they are 8.5's. 

I run rs3 245/40/17 on porsche 17 x 9 ET55 wheels, and up front they rub slightly at full lock on the inside edge. I don't have a measurement on me, but remember there being about 6mm+ of clearance between the strut/spring cup and tire

[DiscobayJoe]

Tips hat to Loren:     Running 245/35/19's in the front, slight rub on outside edge both front and rear:

 

 

 

 

 

 

Swapping for 235/35/19's tomorrow.

 

I also noticed over a really large whoop going too fast in a parking lot that the rear 305's rub too (can't see any rub marks tho, it was real minor).      Based on my experience I would say the maximum size for 19's on a 996  Narrow Body is 235/35/19 and 295/30/19 on 8.5's front 11's rear. 

Edited June 20, 2015 by DiscobayJoe