20 Inch Slicks

[handbrake]

http://www.nagtroc.org/forums/index.php?sh...c=46044&hl=

wonder how these will perform.

HK$6850 each, or about AU$920 without import/shipping costs unless Advan/Yoko will do better locally.

[handbrake]

[handbrake]

[Beer Baron]

oh mamma!

[LSX-438]

interesting. what compounds do they have?

[White 35]

interesting. what compounds do they have?

Im going to order a set and try them out early next year. Ive got a direct contact to Top Racing but the are f**king expensive - maybe Yoko Australia can get them soon?

As far as i can see these are the slicks that the Nismo GTR RC car and the Club Spec edition are using in Japan.

Bet you they have been specifically developed for the GTR because i dont think there is any other cars out there running 20 inch slicks

They will be pretty good i recon...

[Adriano]

TBH for that price, what gain do you expect over an 18 inch setup?

[handbrake]

who knows, they may be no better or worse, then again, there are no comparisons i could find. If you are serious about getting the best track times though tyres are very important and these might be worth a look especially if they were specifically developed for the R35.

also, for those that are concerned about brake clearance/cooling etc or want to use 20 inch wheels, there is at least a slick option now.

[LSX-438]

Will be very intrested to see how you go. The difference in gearing msay have an affect on top speed, acceleration and gear selection. Personally i would try the N1's first but either way VERY interesting.

[handbrake]

actually I dont even have a set of wheels suitable at present in 20inch, so wasnt thinking of this for myself, more posting for others interest as I know if I hadnt gone down the pathway of buying 18 inch wheels I would have certainly considered it.

reading an article last night on which slick sizes I should run, michelin point out the following:

A SPECIAL NOTE ON PORSCHE

Compared to the 27/65-18, the taller size offers several advantages:

1. The increased diameter of the tread band permits easier conformation of the tire to the flat road

surface; the tire's tread “maps” to the road surface more readily. This results in improved temperature distribution and increased performance over a longer duration.

2. The greater diameter also increases the total amount of tread rubber available to transfer

power to the ground, again improving temperature distribution and prolonging performance consistency.

3. The taller sidewall helps cushion the shock of power application, providing more progressive corner exit with less wheelspin during aggressive acceleration.

I dont know enough about tyres to know if this is just marketing BS but has got me researching things more.

the 31/71 - 18 tyres I received second hand were only available in the S7 compound which from all accounts is the worst compund to buy second hand. does anyone have the full list of michelin slicks and compounds available? the internet turns up only a limited list which is posted on the european technique website and one or two other places glabally but no where have I found a list of available sizes which is all inclusive of this larger diameter and sizes/compounds. I assume the 71 diameter comes in S7-S9.

BTW Duncan, what is the N1 relative to the slicks I have been using? does it still come in the same compounds or is it a different entity alltogether?

Edited December 1, 2010 by handbrake

[handbrake]

have a read of this whilst you are all bludging at work

http://www.michelinman.com/media/en-US/pdf...ire_Catalog.pdf

[LSX-438]

BTW Duncan, what is the N1 relative to the slicks I have been using? does it still come in the same compounds or is it a different entity alltogether?

I am led to believe the N1's are their own compound, which is roughly equivilent to S8 but (i am told) a much stiffer sidewall.

- We had to use 200psi to get them to pop the bead when fitting them!

I found them the best tyre thus far. And yes the S7's are basically crap after one day.

Dunno how 20" slicks would go, would love to know. I think Miles used some 19" slicks at Bathurst, with paul using 18's? So a comparison from those guys wouldnt go astray, especially the gearing aspect down conrod... Miles, Paul?

I guess one thing to consider is how long a porsche cup race is vs a sprint session?

The tyres are probably constructed to perform best for typical race duration.

[handbrake]

yes, hard to compare time attack format usage with more longer door to door racing formats.

according to Trevor just now, the N1's are a 9 compound.

[LSX-438]

yes, hard to compare time attack format usage with more longer door to door racing formats.

according to Trevor just now, the N1's are a 9 compound.

s9 hey? (not what he told me!). Anyway i reckon the n1's were awesome, great tyre. It just seems to work better than the others. Perhaps it's the sidewall, i dunno.

[White 35]

fellas the 19s were awesome, i loved them. hard to draw a conclusion between Paul and I because my car was set up a lot better and I also had a lot more seat time over the 5 days Vs Paul only about 3 days. By end of the Sprint i was about 5 sec's quicker than Paul. But ive got no doubt he can do the same times as me when his new car is set up better.

Sure the 18's have more sidewall but my 19s were a little wider i think.

Ive got some video which shows me pulling 299 down the straight and Pauls car on 18's was pulling virtually the same numbers. Really came down to who had the better setup... I was flat till last sec and after backing off and pulling 5th was getting into the chase at 260 showing on speedo.

When i pulled 5th into the chase the engine was working hard touching the rev limiter most of the time so im guessing that if anyting the actual speed was 10-20kmph lower if you know what i mean.

Honestly i dont think we will see much difference between 18s and 19s.

But Dunc we will get some good comparisons at EC in the new year... i'm aiming for a 1.38...

Im sure the Japs have done the testing with 20 inch slicks and if they are using them there must be advantages.... anyway we'll find out soon.

Edited December 2, 2010 by White 35

[White 35]

P.S. have you had a close look at how much wider the 20 inch slicks are Vs your 18's...

There is a Big difference.

If that sidewall on those yokohamas is Stiff - then for sure this is going to be the best option.

Remember we are not really racing on these tyres so all that stuff below may not be that appropriate for our 4-5 lap sprints.

1. The increased diameter of the tread band permits easier conformation of the tire to the flat road

surface; the tire's tread “maps” to the road surface more readily. This results in improved temperature distribution and increased performance over a longer duration.

2. The greater diameter also increases the total amount of tread rubber available to transfer

power to the ground, again improving temperature distribution and prolonging performance consistency.

3. The taller sidewall helps cushion the shock of power application, providing more progressive corner exit with less wheelspin during aggressive acceleration.

Then again maybe im way off????

[LSX-438]

fellas the 19s were awesome, i loved them. hard to draw a conclusion between Paul and I because my car was set up a lot better and I also had a lot more seat time over the 5 days Vs Paul only about 3 days. By end of the Sprint i was about 5 sec's quicker than Paul. But ive got no doubt he can do the same times as me when his new car is set up better.

Sure the 18's have more sidewall but my 19s were a little wider i think.

Ive got some video which shows me pulling 299 down the straight and Pauls car on 18's was pulling virtually the same numbers. Really came down to who had the better setup... I was flat till last sec and after backing off and pulling 5th was getting into the chase at 260 showing on speedo.

When i pulled 5th into the chase the engine was working hard touching the rev limiter most of the time so im guessing that if anyting the actual speed was 10-20kmph lower if you know what i mean.

Honestly i dont think we will see much difference between 18s and 19s.

But Dunc we will get some good comparisons at EC in the new year... i'm aiming for a 1.38...

Im sure the Japs have done the testing with 20 inch slicks and if they are using them there must be advantages.... anyway we'll find out soon.

Can't wait to see the video!

and i will be disappointed with anything worse than a 38! 36's or bust.

[White 35]

Just watched my video footage of the 2.21 lap at bathurst and at 299 on the speedo on 19inch slicks in 6th the rev shift lights are on.

So Dunc im very close to hitting limiter in 6th.

Speedo has to be reasonably accurate i think.

[LSX-438]

Just watched my video footage of the 2.21 lap at bathurst and at 299 on the speedo on 19inch slicks in 6th the rev shift lights are on.

So Dunc im very close to hitting limiter in 6th.

Speedo has to be reasonably accurate i think.

Insane.

yet awesome.

Edited December 2, 2010 by LSX-438