high performance 15" tyres

[Julian West]

searching the Yokohama web-site, I found an interesting tyre spec...

They list an "AVS Intermediate" 345/35 ZR 15. check http://www.yokohamatire.com/04b2e.html for details. There are several suitable sizes offered for the front aswell, all Z rated.

Has anyone tried these? Searching their web-site they list plenty of 'big' 15" tyres, but with low speed ratings.

any comments would be appreciated!

 

[Jim Glickenhaus]

If you search under tires you'll find relevant replies. 35 aspect sidewalls will not give you enough ride height on the street and will destroy your wheels if you hit a pot hole.
Best

 

[ChrisL]

Julian,

A good Yokohama tyre that I have used is the 032R. You can see one pictured in the middle of the "Motor Racing" page of the site you refered to.

This is a street legal tyre that is designed for the race track and is by far the stickiest tyre (including non-monsoon wet coditions) Yokohama have on offer. Its also quite noisy and wares very quickly. Given though that most our cars are not driven all that often, you would probably not need to replace them all that often either.

 

[Jim Glickenhaus]

Chris
What size wheels and tires are you using?
Best

 

Julian,

I used AVS's on a Lotus 7 replica recently, not a GT40, but still V8 powered...so same sort of torquey power delivery at low revs..

They proved a little hard for my liking, with a bit of sudden loss of grip....and it might have been my imagination, but I did sense that I could feel a bit of tyre roll....

However, for the sake of fairness they did replace Yokahama 008R, which are seriously soft and sticky, but only lasted 3,500 miles... at £170/$265 per tyre thats a bit steep!

Neil

 

[Julian West]

MK -IV J6, sure, the diameter of the 345/35 is 24.5 inches as opposed to 25.4 for the 265/50 so I guess it would lower the gearing some 5%...

Chris, I've used the A032r's in club racing for a few years & they are a great tyre, however, not available in large enough sizes for a 15" wheel! If I choose to change to 17" I may well fit A032r's. I currently run A039's on my Lotus & they are great performers & look like a modern motorcycle tyre!

I would really like to keep 15" rims if possible, I like a bit of sidewall movement in a tyre, & also ride quality is better. With 17" rims the geo has to be much more accurate & I'm not too sure about the accuracy of the stock GTD setup!

It seems (as I thought!) the only solution for 15" rims in the UK is the race tyres used by Malcolm & the other competition chaps, but I understand these are not ideal for road use due to the thin sidewall construction. ho-hum!

Seeing the V-rated 345/35/15 Yokohama I thought I'd made a great discovery, but perhaps not!

 

[ChrisL]

Sorry Julian, it seems I totally overlooked the 15" figure in your comments

My GT40 is not yet complete so I haven't had the oportunity to try the 032Rs on it yet.

However, RF offer this tyre as a standard fitment option on the RF40s here in Aus in 205/55ZR 16 front and 255/50ZR 16 rear. It seems that they might be a little less pricey here though since you'd buy this set at around $US500 (we are closer to Japan).

To give other people an idea of their performance advantage, I was able to improve my lap times (compared to Yokohama 509s) by almost 4sec on a circuit that I would normally lap in the 1min 40s. At a rough estimate, I'd say we were talking about 6 car lengths!

 

[Robert Logan]

The Yokies we use are some three years old and Dunlop have recently launched a new "R" tyre which I have had a friend do back to back tests. The car was similar in weight and weight distribution and the people involved in the test are from the race industry here in Australia (one was my engineer) and there was little to seperate the two manufacturers.

Yokahama have also recently launched a new range of tyres (not available for our cars - perdominently available in 17, 18, 19 and 20 inches ) and I would bet these will be a better tyre. We have not tested them but I am looking at making a special set of rims to do exactly that.

The tyres is exactly where we started the design of our cars and as we enter a new era of racing our cars this is where we again started.

These and only these are between you and the road and are the single most important things on any car.

Best wishes,

Robert