Martin S.

I have found this Bulletin to be very helpful, especially when trying to visualize a specific wheel...noting there are 15 different wheels that Porsche offered for sale on the 993.....alas, I tried to attach it the complete bulletin...too large, so I have attached only the data on wheels...whoops too large too....

if you care, e-mail me and I'll send to the pdf.

pirahna

What?

Martin S.

I have a Porsche factory technical bulletin that specifies all the tire and wheel options for the 993 car. The pdf file exceed the maximum for Rennlist...so if one wanted the file, send me an e-mail mfschacht@gmail.com and I'll e-mail them the pdf file, still confused?

FlatSix911

This should help ...

Mike J

This has been on pcarworkshop for several years - as well as most of the TSB's....

Kein_Ersatz

Thanks!

Martin S.

Thanks Mike....I am glad my little post flushed out pcarworkshop.

Wish I could figure out how to view more than the first page of the TSB. I looked up the summer tire bulletin, and couldn't get past page 1 of 10. I'll have to try it again.

Kika

36/44 tire pressure for 18s seems really high. Is it because current tire technology can manufacture a sidewall that is stiffer with less pressure now?

il pirata

Good question. There was a recent thread with a lot of discussion on tire pressure but no real resolution...at least based on fact. FWIW I run 36/44 on my C4S with twists and Conti DW tires and on good roads it feels great...on marginal surfaces it feels like a bit too much pressure. The problem is there are so many variables...I am at RS height with PSS 10s set at 4F/5R, etc etc. Porsche was real adamant about not running any lower pressure...most likely due to some cars being run at very high speeds. Is there any verbage from tire manufactors or Porsche on the current generations of tires that recommends running lower pressure?

Kika

I suspect that there is also a bit of liability involved. So the recommendation may not necessarily translate to optimal performing, but what the Insurer deems as low risk.

I know some people believe that just because the factory recommended it or designed it that way, it must be the best performance. Likewise there are other forces in play like money, federal regulations, insurance risk etc...

in any event, clearly there are many other tire choices available now that were not available at the time of the bulletin.

DanL993

I agree....good question. I currently run 36/38 front/rear based on what I've seen here.

Any exparts out there that can help beyond the speculation on insurance risk?

Vq-1

Is anyone running 235/45 fronts & 275/40 on there 993 carrera NB on 18" turbo wheels?
Any fitment or performance issues?

Martin S.

Nitto NT-01 Tires:
245/40/18 front
275/35/18 Rear

On the rears, the next step up is a 305 tire and I don't want to buy one to see that it fits...it does't look like I have 30mm of extra clearance available.

In 17"
235/40/17 Front
275/40/17 Rear
Again NT-01

I buy them Heat Cycles too, and extra $15 a tire.

Vq-1

Cool, your saying its best to have the same aspect ratio/profile when going a size bigger.

Vq-1

Another question is what is the tallest tire one can run on their 993?
Here are a few numbers:

265/35r18=642.7mm 25.3 inches
265/40r18=669.2mm 26.4 inches
270/40r18=673.2mm 26.5inches
275/40r18=677.2mm 26.7inches
275/45r18=704.7mm 27.7inches