Tweety

Hello,

I am a new memeber, hello all...

I just purchased a set of Yokohama A048's for Vintage racing on my 1969 911 (205/60/15), and this size is still pretty new, so I am having a hard time getting anybody to cough up correct tire pressures. I will like to find out if anybody has any exp with them and what cold pressures should be used. The car weighs about 2000 lbs.

Thanks,


Steve

Professor Helmüt Tester

I've run them in a 'spec tire' series, on a ~1700 lb. sports racer. Shoot for hot pressures in the 28-32 lb. range, then tweak camber & pressures with a good (good = insertion probe type) tire pyrometer.

They have a tendancy to 'go off' in 10-15 hard laps, and get greasy. They also lose grip quickly, being fastest on the initial heat cycle (i.e. 'stickers'), then falling off a bit on the following 2-3 heat cycles, then falling into a black hole of 'not much grip at all'. Me...and my fellow 'spec tire' competitors...all hate the 048's.

But that's just my opinion.

JackOlsen

That sounds a lot like the A032R's, which are also pretty lousy, considering. I shoot for about 33/36 hot, on a 2400 pound car but with tires so wide (275/315) it's not easy to get heat into them.

I may be too low on the pressures, since I get a few good laps and then the greasy nonsense starts.

DGaunt

Compared to the 032Rs, I find them to be PIGS when cold. Not too much choice in 15' any more.

Professor Helmüt Tester

Not much choice in 15" anymore ??? You're kidding, right ?

Let's just talk DOT R-types in 205-15, the size which Steve first asked about -

Kumho (3 different tires)
Hankook
Hoosier (2, plus a sea of bias ply choices)
Toyo
Yok (3)
Goodyear
Michelin
Avon

...and we haven't even got to 'slicks' yet. 15" is THE wheel size for tire choice in race tires.

Tweety

Actually, there are not too many choices in a 60 series. The series I race with has rules that will not allow a 50 series tire. The only choices that I can find in a 60 ( in 15 inch) series Comp tire are as follows..

Hoosier R3S04 - These are pretty good, but they are 215/60/15, so they kind of screwed up my gearing. These used to be the only 60 series tire that were available, other than importing from Japan.

Then Yokohama came out with the A048, so now I have 2 choices..(oh boy)

Kind of a dumb rule, but its the rules, so I have to deal with it.

Thanks for all the feedback.


Steve

Professor Helmüt Tester

Mandatory 60 (or taller) series tire ? Sounds like a vintage group. Yeehar...you can run bias ply tires then. Hoosier Street TD's...DOT-rated bias ply race tires. You can drive like a juvenile delinquent on bias ply race tires...and everyone will be able to see that you're driving like a juvenile delinquent...great fun and much more forgiving than radials. I run them on my loud obnoxious V8 vintage racer, and love'em.

Terry L

A048s are the stock tires for the Lotus Elise with the sport pack. The concensus is that 28 lbs hot is the right pressure. More than that and the car skates. These are 195/50s on 16s in the front and 225/45s on 17s in the rear.