Fuchs 7R wheels with 215/60 R15 Pirelli CN 36 tires

[CA lover]

Hello

Here are some pictures of my 1973 Longhood coupe with Fuchs 7R wheels. I used longer wheel studs with 13mm spacers on the rear axle.There is enough space between the tire and the aftermarket oil line on the inner side .

[911MRP]

If it helps my 73 Carrera RS has original rear spacer which from memory is 7mm and iirc RS had slightly longer studs . Fit easily under Carrera flared rear arches with the cars original 7J Fuchs. Definitely original rims as have the correct dates one of just 205 GO white RS original blue painted rims — still got Mexico blue there. The car’s factory build papers show 215/60 Vr15 Pirelli CN 36 tube-type rayon belted if the time were fitted at conversion order when new. Compatible configuration with the standard for RS oil cooling plumbing.

Steve

[frederik]

Interesting and thanks for posting. I have 7R wheels on my 2.2S, currently with 195/65 P6000 tires, but eventually I'd like to move to CN36. There are two types of 7 inch wheels if I'm correct, so 7J for the RS is different from the 7R, where all the extra width is on the inside as with the 911R?

I wish the CN36 tire came as a 195 or 205 as well.

[skinnerd]

CA lover....is that really a 215/60 R15 Pirelli CN 36 fitting on the back of your 1973 911 longhood?
Hard to tell if your suspension is raised to make this happen?

[BOYER73S]

Interesting and thanks for posting. I have 7R wheels on my 2.2S, currently with 195/65 P6000 tires, but eventually I'd like to move to CN36. There are two types of 7 inch wheels if I'm correct, so 7J for the RS is different from the 7R, where all the extra width is on the inside as with the 911R?

I wish the CN36 tire came as a 195 or 205 as well.

Yes 7J is RS and 7R is as you describe more with on the inside as me how I know spacers are required

[frederik]

I wonder what tires Porsche recommended in period for these 7R wheels. 215 seems really wide, 185 too small.

[rattlecan]

Yes 7J is RS and 7R is as you describe more with on the inside as me how I know spacers are required

My car is a '71, no flares.
I'm confused. I have a set of 7J's and they require a spacer to move the wheel inward.

I have 15 mm spacers and thinking of trying 13 mm spacers to move more inward as they touch when going over a dip or large depression in the highway.

What cars ran 7J's and which cars ran 7R's?

Thanks

[911MRP]

The early model 73 RS up to around spring of 73 was afaik the only 911 to run the 7J 15 Fuchs at rear. From around spring ( possibly starting from around mid March) some fitted 7J and 8J to the RS with Pirelli or Dunlop 60 series 215/60vr15 covers of period. 7&8 were “no M-option number” request. The tyres used at time cars were new were tube type radial rayon belted 60 aspect ratio at rear but this was superseded to steel belted tubeless starting around the mid 70s. Fortunately the 7R Fuchs already had the necessary safety humps around the circumference and modifications to seat to be suitable for the tubeless and for the valve required in switch to tubeless. I don’t believe it is now permitted practice to fit inner tubes in the modern tubeless tyres of today and pretty sure not permitted to run tubes 60 aspect ratio or lower either!

The Fuchs changed around time of the G series impact bumper to become hub centric and some details are noticeable differences so are not regarded as correct for pre 74. That authenticity may not matter to some owners but does to others who can spot the difference.

Although it was a limited edition homolgaton special the 73 Carrera RS was I believe the first “production” 911 said to have run the now “trademark” staggered front and rears— 6J and 7J respectively. See my earlier post for some details of the original configuration of rear wheel tire spacer etc still on my early RS.

I’ll leave it to others who are more knowable on the period before model year 73 to discuss the 7R tyres and vehicle applications. I have however shared old technical infomation sheet From Porsche regarding the position on compatibility of earlier humpless wheels with tubeless tyres. That and the equivalent latest position might be of interest as in breach potentially could be an issue if dealing with knowledgable regulators like TUV and maybe even relevant in declarations to insurers. It hard to see how the earlier 7J rims can be permitted (legal?) if used in combination with the current tubeless tyres and valve based on the technical information from tyre manufacturers back then that seems applicable today .

Hope this helps give some historical hobby context but some of the things might be no longer up to date or relevant in some regions. Please note I’m no expert in such things so recommend folks get up to date advice in such matters from suitably qualified experts or or regulators like TUV in relevant region on any safety critical legality matters.

Steve

[70SATMan]

The early model 73 RS up to around spring of 73 was afaik the only 911 to run the 7J Fuchs at rear in the period before the impact bumper 2,7 Carrera of model year 74. Although it was a limited edition homolgaton special the RS was I believe the first “production” 911 said to have run the familiar trademark staggered front and rears— 6J and 7J respectively. See my earlier post for details of the configuration on my early RS . I’ll leave it to others who are more knowable on the period before model year 73 to discuss the 7R tyres and vehicle applications.

Steve

Well yes but, not quite. The discussion is around the 7R. The ‘68 911R ran staggered 6” and 7” and was considered a very limited production run. Makes me want to go look at the original 70S liteweight again because that would have been the next logical production run to use the staggered wheels.

[Veronica87911]

I have a 72 T with 7Js all around shod with Dunlop Direzza 205/55s all around. I was thinking of getting CN36s when these Dunlops are done, 185/70-15 front and 215/60-15 rear. Will he 215s fit ok in the rear?