Tire Sizes for Fuchs

[tlevine984]

Picked up a pair of 8" fuchs. Currently running 6/7's on my 911SC will move to a 16x 7/8 setup.

Will I need spacers for front or rear wheels?
What tire sizes are optimal - grip and a selection of tires?
What tires are recommended?

[Fly911]

For the 7"x16"ET23.3 front rims you can get 205/55-16 or 225/50-16 tires. no spacers needed, the 225´s may a tight fit, but should work fine with a little bit of fender lip rolling (use a wooden base ball bat between the wheel and fender, and roll the car back and forth until the lip is tucked in. This will not show on the outside of the fender).

For the 8"x16"ET10 rear rims 245/45 will work with plenty of space, no spacers required. However, to fill out the fender "properly", you might want to have some spacers here. Install the wheels and measure the clearence between the tire and fender, and buy spacers to fill the gap.

[Boomtown Rat]

I run 7x16 / 8x16 on two of my 3.2s with 205/55 R16 in the front and 225/50 R16 in the rear. No spacers are needed. In Germany, running 245/45 R16 is only allowed on the 9x16 rim. Therefore, I have no advice on running the 245s on an 8x16 in the rear. Nevertheless, the 225/50 R16 on the 8x16 is more than adequate and, I think, also very good looking.

[megerian]

I have 245/50/16 on my 8 inch rear Fuchs. The main reason being that 245/45/16 was next to impossible to find, and the 245/50/16 fit and look great.

When I was looking, all I found in 245/45/16 was Fuzion, and since those were the ones I was replacing, and the previous owner of the car stated that they were not great tires, and prone to flatspotting, I expanded my search to include 245/50/16 and found many options.

[911SauCy]

Not to hijack, but while we're on the topic.

I'm currently having the same quandary...

Recently purchased a set of 17x7/9 ET23.3-f and ET15-r, Euromeister Fuchs replicas

Was planning on 215/45F and 245/45R...(yes Nitto makes NT01s in a strange size)

Any red flags with my thoughts!?

The big thing for me is I want the sidewalls to look similar F/R...no Chubb up front and stretch out back.

Perhaps a 255/40 for the rear?

[Bill Verburg]

Originally Posted by Boomtown Rat

.... In Germany, running 245/45 R16 is only allowed on the 9x16 rim....

That's interesting, I'd never heard that before

Most(all I could find) tire manufacturers spec a 7.5 - 9" wheel for 245/45 x16. You certainly get the best performance from a 9 but It's hard to understand why TÜV would insist on 9.

[Bill Verburg]

Originally Posted by 911SauCy

Not to hijack, but while we're on the topic.

I'm currently having the same quandary...

Recently purchased a set of 17x7/9 ET23.3-f and ET15-r, Euromeister Fuchs replicas

Was planning on 215/45F and 245/45R...(yes Nitto makes NT01s in a strange size)

Any red flags with my thoughts!?

The big thing for me is I want the sidewalls to look similar F/R...no Chubb up front and stretch out back.

Perhaps a 255/40 for the rear?

No problem w/ 215/45 & 245/45 except that both are a little short, I have 225/45 & 255/40 x17. Even on a lowered car these fit & look fine.

[Bill Verburg]

Originally Posted by megerian

I have 245/50/16 on my 8 inch rear Fuchs. The main reason being that 245/45/16 was next to impossible to find, and the 245/50/16 fit and look great.

When I was looking, all I found in 245/45/16 was Fuzion, and since those were the ones I was replacing, and the previous owner of the car stated that they were not great tires, and prone to flatspotting, I expanded my search to include 245/50/16 and found many options.

You have to be careful fitting taller tires in back, besides the basic fitment issue you also need to consider the effect on gearing.

For years the base rear tire has been 225/50 x16, one of the big advantages of 245/45 x16 is that is is slightly shorter w/ a commensurate salutary effect on gearing
a 245/50 is taller w/ a consequent hit to the gearing profile.

[Hunt3R]

If you guys wondering about tire sizes just go to TireRack.com and search for tires in whatever size you're curious about you can see what is available, at least from tirerack.com, which is most available tires. And when you click on a specific tire from your search results, you can then click on the "Specs" tab and they'll show you all the other available sizes in that tire below so you can compare the specs.

For example, here's the tires I have on my 911 right now, check out the Specs tab:
Michelin Pilot Sport A/S Plus

In particular, look at the 'Overall Diameter' and 'Revs Per Mile', my 16x7 Fuchs have 225/50/16's with a 24.9" overall diameter and my 16x6 Fuchs have 205/55/16's with the same 24.9" overall diameter. Notice the 'Measured Rim Width' too, if you're putting that same tire on a different width rim than what they tested with here then it will stretch/squash it slightly and change the overall diameter, slightly. A 1/2" different width won't make a huge difference, but there's formulas for that if you want to get real specific just look it up.

You can compare 17" sizes here too, obviously you want to aim for something that would give you approximately the same overall diameter as the OEM 16's. So i.e. a 255/40/17 has an overall diameter of 25" tested on a 9" width rim, so only 1/10" off from OEM and the revs per mile are very close too. Go much more than a tenth or 2 or 3 in diameter and you're really gonna be changing the overall size of your tires a lot.

Another good thing about this website is you can research tire weights here in the specs too.

And BTW, the Porsche manual recommends the same size tires on a Fuchs 6/7 pair as they did on the 7/8 pair. 205/55/16 up front and 225/50/16 in back.

[msterling]

Originally Posted by 911SauCy

Not to hijack, but while we're on the topic.

I'm currently having the same quandary...

Recently purchased a set of 17x7/9 ET23.3-f and ET15-r, Euromeister Fuchs replicas

Was planning on 215/45F and 245/45R...(yes Nitto makes NT01s in a strange size)

Any red flags with my thoughts!?

The big thing for me is I want the sidewalls to look similar F/R...no Chubb up front and stretch out back.

Perhaps a 255/40 for the rear?

The 255/40-17 NT01 on the rear should be a good fit and are just the right diameter to match a stock setup. If you can get a 225/45-17 to fit up front without interference you would have a good match. I think the 275/40-17 would also fit the rear, though you might need spacers and gearing would be effected.

There are not so many choices for 16" and 15" stock Fuchs. I have 15x7"/8" and the pickings are slim.

Wow; everyone answered at once. Looks like we mostly agree.

[911SauCy]

Originally Posted by Bill Verburg

No problem w/ 215/45 & 245/45 except that both are a little short, I have 225/45 & 255/40 x17. Even on a lowered car these fit & look fine.

Bill...

Thank you for the insight!!

The "short" look is exactly what I was afraid of.

225/255 were my initial instincts but I have heard all different things, trying to clear this up through some folks with the current set-up.

What year/model are your 17s on?

[911SauCy]

Originally Posted by msterling

The 255/40-17 NT01 on the rear should be a good fit and are just the right diameter to match a stock setup. If you can get a 225/45-17 to fit up front without interference you would have a good match. I think the 275/40-17 would also fit the rear, though you might need spacers.

There are not so many choices for 16" and 15" stock Fuchs. I have 15x7"/8" and the pickings are slim.

I'll be rolling all fenders as a precaution, so I think the 225s should snug right in.

The goal is low hot-rod...not AX or track day car.

[Bill Verburg]

Originally Posted by msterling

..I think the 275/40-17 would also fit the rear, though you might need spacers.

There are not so many choices for 16" and 15" stock Fuchs. I have 15x7"/8" and the pickings are slim.

275/40 x17 will fit but it's one of the most difficult fitments I've ever tried, the wheel wheel is only ~ .5" wider than a 275 and so the wheel has to be centered w/ very little leeway, even then the oil lines and trailing arm adjusters as well as the lips will all need to be moved or massaged.

275/35 x15 is a far easier fit because the tire is so short

I agree the choices in 15 and 16 are slim but there are some good ones though usually limited by size choices.

W/ 7 & 8 x15, I liked the oe fitment on my Carrera, 205/50 & 225/50 tires, these are very short, the car can be run very low and the gearing is great

[Boomtown Rat]

Bill,

Its just getting much more difficult in Germany now. TÜV adheres to Porsches "Felgen- und Reifenfreigabe" List (Porsche's officially offered production options at the time). I am even having difficulty getting newly registered cars to run 7x16s up front, because only 6x16 and 7x15 were officially offered on the front axle for narrow bodied cars. Its all pretty irrelevant, because we all know that a 7x16 Fuchs on the front axle works just fine. The same probably holds true for a 245/45 R16 or 245/50 R16 tire on an 8 Inch Fuchs on the rear axle. Also, now we can only run "N" rated tires. When I started with all of this, I could run almost any combo that I wanted. It was in the power of any TÜV technician to "wave" the combinations through.

I had originally planned on running 7x16 (front) and 9x16 (rear) on the pictured car, but getting approval requires an individual expert opinion from a leading technician at TÜV - and that's discretionary and expensive. I think TÜV has woken up to being a capitalistic company vs. their original mandate to be a non-profit technical safety organization.

Now back to regular programming.

[Bill Verburg]

Originally Posted by 911SauCy

I'll be rolling all fenders as a precaution, so I think the 225s should snug right in.

The goal is low hot-rod...not AX or track day car.

225/45 x17 is actually an easier fit than 205/55 x16, the shorter the tire the easier the fit ans a 225/45 x17 is ~.8" shorter than a 205/55 x16

[msterling]

Originally Posted by Bill Verburg

275/40 x17 will fit but it's one of the most difficult fitments I've ever tried, the wheel wheel is only ~ .5" wider than a 275 and so the wheel has to be centered w/ very little leeway, even then the oil lines and trailing arm adjusters as well as the lips will all need to be moved or massaged.

275/35 x15 is a far easier fit because the tire is so short

I agree the choices in 15 and 16 are slim but there are some good ones though usually limited by size choices.

W/ 7 & 8 x15, I liked the oe fitment on my Carrera, 205/50 & 225/50 tires, these are very short, the car can be run very low and the gearing is great

I am currently running 205/50-15 front, 225/45-15 rear NT01's for autocross. They are very short at 22.95" dia. but it puts the car down low and lowers the gearing just like you say. Frankly it looks a little goofy but they are not my street tires. For street I have 205/55-15 front and 225/50-rear with NLA Yoko ES100 tires. They are not nearly so "short".