DDK - Die Deutschen Klassiker

I am not sure how these manufacturers price these ‘period’ tyres. Surely they involve no further manufacturing than a normal tyre, apart from a rounded off shoulder. The compounds are modern used for the construction of them, so what else involves the huge price hike. Years ago when doing the Peugeot Gti challenge PTS arranged a visit to the Dunlop factory in Birmingham to see how competition tyres were made. I would say the process is no different and those tyres were not a fortune?
Is it period look tax?

911hillclimber wrote: ↑Thu Jan 12, 2023 9:32 am And £319 plus fitting EACH.

Did you mean plus VAT?

Lightweight_911 wrote: ↑Mon Jan 02, 2023 11:59 am .

When you have different width wheels front & rear it's normal practice to reduce the aspect ratio of the rear tyres so that the overall diameter remains roughly the same

.

That Ferrari wheel pictured above has given me an idea.

Rather than reducing the aspect ratio of the rear tyre, why not look for 5.5 x 14 Fuchs (to be used on rears) and widen them to 7-inch? That way, 205/70x14 can be used, which has exactly the same rolling diameter as the 185/70x15 (642mm versus 641mm). Daft idea probably, but I think it will work.
Many classic tyre brands if not all, are available in that size.


Anyway, regarding the RS tyre 215/60x15, the actual width (inflated to the correct pressure) of the CN36 is about 230mm, so in spirit it's a 225 tyre really, and therefore too wide for the 7R wheel. An inch spacer would be required otherwise it'll be too close to the spring plates. I'm of the opinion that a spacer as wide as 1-inch is impractical.

Dunlop Classic is available in 215/60x15. I will try to find out what is the actual width of this one.

Nine One One wrote:I am not sure how these manufacturers price these ‘period’ tyres. Surely they involve no further manufacturing than a normal tyre, apart from a rounded off shoulder. The compounds are modern used for the construction of them, so what else involves the huge price hike. Years ago when doing the Peugeot Gti challenge PTS arranged a visit to the Dunlop factory in Birmingham to see how competition tyres were made. I would say the process is no different and those tyres were not a fortune?
Is it period look tax?

Tooling and development sign off cost of a tyre is normally amortised into the piece price. Inevitably these are low volume, hence each tyre carries a high percentage of that cost.

Oh and also Porsche tax

IanM wrote: ↑Thu Jan 12, 2023 2:27 pm
Anyway, regarding the RS tyre 215/60x15, the actual width (inflated to the correct pressure) of the CN36 is about 230mm, so in spirit it's a 225 tyre really, and therefore too wide for the 7R wheel. An inch spacer would be required otherwise it'll be too close to the spring plates. I'm of the opinion that a spacer as wide as 1-inch is impractical.

I ran a combination of 205/55 & 225/50 x 15 tyres for a while on deep six & 7R* Fuchs wheels - including a high speed trip down to CLM & back - on my old 911R-inspired car without any clearance problems (using a 15mm spacer on the rear).

I can't find any close-up pictures of the wheel/tyre but these shots show the car with that combination:






*7R-spec wheels were made for me by DP Motorsports in Germany (from deep sixes supplied by me)

Thanks for the photos Andy. The tyres look good (American noughties style) but it seems to me that there's too much gap in the wheel wells. I think 60 or 65 series would be closer to factory spec.

.

I agree - my post was just to verify that a 7R wheel equipped with a 225 tyre can fit on the rear of a LWB car.

I later swapped them for a set of more correct 185/70 & 215/60 Avon CR6ZZ's ...

Lightweight_911 wrote: ↑Thu Jan 12, 2023 8:45 pm .

my post was just to verify that a 7R wheel equipped with a 225 tyre can fit on the rear of a LWB car.

Understood.

That looks fantastic.

From what I read in Pelican recently, the CR6ZZ is a little narrower than the CN36, so will fit better in a narrow body 911 (without RS flares).

I'm still waiting for a reply from Dunlop..

As an aside, AVON are closing it's motorsport tyre manufacturing in the UK at the end of this year.
Not sure where the road spec tyres are made.

My two bob's worth, when I was doing 911 I wasn't too shy on the cost of it all, but there is no way I'm paying that much on a consumable item.

Horses for courses though.

Thought long and hard about the Dunlop blus but in the end decided the artwork on the sidewall was too exciting for me.

Went with Vredestein 195 Ultrac that were about £75 each fitted and scored very favourably on Alltyretests.com particularly in the wet.

Very happy with them so far

Sent from my SM-G981B using Tapatalk

g3ngs2 wrote: ↑Tue Jan 17, 2023 12:26 am My two bob's worth, when I was doing 911 I wasn't too shy on the cost of it all, but there is no way I'm paying that much on a consumable item.

Exactly... consumable item.

May I point out that when the Porsche 901 was first introduced in 1964, the original tyre size was 165R15 (165/80R15), which has a rolling diameter of 645 or 646mm.

So, that rolling diameter is the BENCHMARK when it comes to choosing tyre sizes... especially for the rear.

205/65 equates 647mm (only 2mm taller). Perfect for the 7R (with an inner tube).

gridgway wrote: ↑Wed Dec 21, 2022 3:57 pm So apart from how they look, what are the compromises? I think you need to do a better sales pitch for your CN36s than that!

You must have missed a few points i have made. I guess this is the strongest one, because this is independent.

https://www.cinturato.net/images/test-c ... s-0716.pdf

but if you read the coments above i think i explain quite well why having a tyre made for you buy one of the orlds best tyre manufactures with modern compounds and a caracass designed to compliment your chassis and the way it presents the tread to the road makes a superior tyre.

Interesting that Porsche themselves asked Pirelli to make these tyres for them. Porsche then tested these tyres and gave them the N homolgation. then the german car magazine did a back to back tyre test and the Pirelli knocked every other tyre out of the park.

Lightweight_911 wrote: ↑Wed Jan 04, 2023 3:15 pm .

I know it's a bone of contention but I ran 7R's without tubes on various early 911's (along with countless other owners) for 10+ years & thousands of miles without any problems ...

.

If I'm going to run 215/60 Pirelli CN36 on 7R's without tubes (public roads only, not trackdays), I will need TR415 stem valves. I understand that some valve brands are really fat and some a little slimmer, so which brand is the best one? Is there a supplier in the UK or would I have to buy from the USA like Stoddards?

.

These look like the 'stubby' ones I've always used (assuming the same as in their photo):

https://www.ebay.co.uk/itm/141066687360 ... R7i-lp3EYQ

.

Lightweight_911 wrote: ↑Sun Feb 05, 2023 1:48 pm .

These look like the 'stubby' ones I've always used (assuming the same as in their photo):

https://www.ebay.co.uk/itm/141066687360 ... R7i-lp3EYQ

.

Thanks. I've just ordered Milton TR415 from Amazon as they appear to be even stubbier.

911hillclimber wrote: ↑Sun Jan 15, 2023 9:28 am As an aside, AVON are closing it's motorsport tyre manufacturing in the UK at the end of this year.

Where did you get that info from? Are they relocating their manufacturing to another country or are they closing down for good?

Not sure where the road spec tyres are made.

Most, if not all, road-spec classic Avons including CR6ZZ are made in England.

The Dunlop SP Aquajet is also made in England but unfortunately their 185 is not available in 70% profile.