Pirelli CN36 tire and wheel question

[Chris Pomares]

At LUF8 I noticed a handful of 73RS's with 7 and 8 inch Fuchs. Not 6 and 7. Most had 185 and 215 CN36's. From what I can find the 185/70/15's are recommended for 5.5 and 6 inch wheels. Is the 185 on the 7's just for show or will the 185 stay in the bead lock grove under load.
Do you use tubes with these?
https://www.stoddard.com/sic3565700-sic-356-570-0.html

[gled49]

That would be normal tire fitment for 7’s & 8’s.

[Richy]

As gled49 replied , 7's came with 185's and they work fine .

[911MRP]

The original fitment on 1973 model year RS was tube-type rayon-belted Pirelli branded Cinturato CN36 of 185/70 VR 15 on 6 rim then around springtime when some used the 7 rims at front (with optional 8s rear getting the then ultra low AR 215/60VR15 ). The construction of the Pirelli CN36 tyre changed around the mid 70s during the impact bumper era when they were redesigned as tubeless, steel-belted. Those so called flat Fuchs rims for that era already (unlike previous Fuchs generation) had been designed with safety humps in readiness for the coming of tubeless. The adoption of tubeless was mirrored by other tyre suppliers around that same time. I have previously posted pictures of my NOS cn36 tube type vintage tyre and original RS and tyre company literature about this point in other threads.

I don’t know about the recommended rim sizes for the current generation of Pirelli cn36 with Porsche rating. Dougal of Longstone Tyres in the UK who posts here from time to time was I believe instrumental in these current covers being made so should be able to advise. My understanding is tubes are not recommended for use with tubeless tyres but I defer to Dougal and other specialists on such safety points.

Steve

[Chuck Miller]

As noted before...

I've run the CN36's in period and hated them ... They were unpredictable, wore fast, and turn rock hard prematurely...

The NEW CN36's are a completely different story ...
Classic tread pattern, contemporary compound....

I've driven them at 185 x 70's on 7's all around on stock fenders... and 185 x 70's and 215 x 60's on 7's and 8's on flared fenders... And they were VERY impressive on the road and in the canyons...

Hope this helps,

cm

[Chris Pomares]

Thanks guys for the info.