For those with real 7R Fuchs...
 

My understanding has been that 225/50 x 15's really do work with 7R's on early narrow body (pre 74) non flared cars. Any disagreement? Qualification? Thanks, Jim

Here's proof.

http://forums.pelicanparts.com/uploa...1333678000.jpg

Frank

Thanks Frank. Did you need spacers?

I also ran 7s on the front of a 73 no spacers - Toyo RA1s IIRC which are pretty fat. 8s on the rear but it had SC fares

Did you have to roll the fender lips???

Will they fit if the factory lines are used with a front cooler???

curious,
chris

Spacers on the rear only, no fender-rolling, just longer wheel-mounting studs.

Your mileage may vary...

Frank

I dont 'think' they were rolled - if they were it was before I got it.

those are 7 x 15 fuchs, not 7R as moneymanager asked about
but with spacers and longer studs, the 7R should work too

just sayin... ;-)

Oh - sorry yikes I forgot about the 7R vs 7...dooh.

What's the difference between a 7 and a 7R?

Thanks,

Frank

Offset...where the wheels lie under the fender. The 7R wheel sits 26mm closer to the center of the car than the normal 7...making some tires fit the wheel well better, though 26mm is often too much and requires use of a spacer to position the wheel further away from the center.

That and about $1500 a wheel...

The 7R has a 49mm offset the 6x15 and the 6x16 have 36mm offsets. One inch =25.4mm
The 7R has the full inch(25.4mm) added to the INSIDE. Divide 25.4 by 2 you get 12.7. Add 36mm plus 12.7 and you get 48.7mm offset. The later 7x15 Fuch added the inch(25.4mm) to the OUTSIDE. 36mm minus 12.7= 23.3 They are VERY different wheels.
I tried to get a 7R offset wheel under my 1967 and deceided to go with a 6 1/2 inch Fuchs of my design. A Jim Lyons, Denver/Al Reed, LA custom with a 42mm offset and 5mm spacers. 1/2 inch(12.7mm) to the inside. 12.7 divided by 2 = 6.3mm + 36mm= 42.3 offset. I just didn't want to run that much negitive camber on my street car to fit a 7R under the lip. I would have had to go to a much wider spacer and for me too much negative camber. This is with a 205 not a 225mm tire. I only have a 1/4 inch on the inside to the spring plate nut and less than a 1/4 inch to the outside and thats grinding 1/2 the spring plate nut next to my sidewall.
You get offset by finding the midpoint of the width and measuring to the hub mounting surface. The midpoints are those dots on the lines on the chart. By the way you probally know this, you measure width to the bead lock not the outside edge of the wheel. The Deep 6's and 7R are an exception as they have no inside bead lock, just a lip. You will see pictures of them,(NOS I'm told) on the link provided. Most wheels are a 1/2 inch to a full inch wider than their measured width.
1969(narrow body) and later cars don't have the 64-68,(really narrow body) issue, as they have some rear fender flair. Check the Pelican link. I reference 16's but think of them as 15's. You can find Jim Lyon and Al Reed in the directory of SoFine9.com

Pelican link.
http://forums.pelicanparts.com/porsche-911-technical-forum/648605-911r-deep-7-wheel-group-4-wheels-5.html#post6669487

Chris Pomares 912 POLO
http://forums.pelicanparts.com/uploa...1333752297.jpg

Like I said, the 7R sits 1" closer to the centerline of the car than the plain 7. And yes it costs an extra $1000.

Is there anyone else who can comment on my original question: do 225/50's always work with the 7Rs?

225's will fit on the wheel. The question is will they fit on certain cars. What year is your car and how much negative camber do you want to run in the rear? I would think there are 69 and later cars with spacers and reasonable camber with 225's. For pre 69 cars you are going to really have to lay in a lot of neg. camber.

Notice the question: will 225's on 7R's work without issues on early (narrow body, pre flare) cars?

I got it. 64 to 68 cars are narrower in the rear than 69 to 73 cars. I couldn't fiqure a way to get anything wider than a 205 on my 67. Maybe others had better luck. Up top you said pre74 cars. Jim I assumed you thought SWB and LWB cars had the same rear fenders. My fault, sorry.

$MGR, I'm running 225-50-R-15's on the rear of my 73 Coupe. Harvey Weidman custom made me 7R Deep-6's for the rear. Also running a 16mm spacers on the rears. Have then shod with BF Goodrich G-Force Sport tires.

It's a stock 73 T body, no flares, no rolled fenders.

Steve

73 911 T MFI Coupe, Aubergine

An absolute answer is difficult.
Factors: One, all 225s are not the same. I have a stack of 225 Hoosier race tires and a set of 225 something or others, and the Hoosier stack is significantly taller than the other.
Second, all 911s are not the same, even side to side. There was a bit of inconsistency back then.

So far we have two people who've actually run 225/50's on the rear of a pre 74 non-flared car with 7R's; both needed spacers. Anyone else been successful at this?