Yokohama A048R correct tyre pressures

PostPost by: Jago » Sun Jan 15, 2017 11:06 am

Hi Guys

I am running 6x14' minilite wheels with Yoko A048R tyres and am not sure what front and rear tyre pressures are appropriate? The car is 1969 Elan FHC S4 prepared for hillclimbs and sprints. It has adjustable suspension so can be 'tweaked' for camber etc although I haven't messed with this as yet. I am running around 20 psi on road and higher I go it seems to get more nervous/twitches.

Any feedback would be helpful.

Thanks

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PostPost by: rgh0 » Sun Jan 15, 2017 11:12 am

On the track I run 31 to 32 PSI hot all around on 175/60 x 13 Yoko A-048R. This is the pressure that Yokohama recommend and I find it about right. Some people with lighter cars run them a bit lower but i find the handling looses the sharp feel I like

On the road i would run the a little softer maybe around 28 to 29 PSI hot

cheers
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PostPost by: ecamiel » Mon Jan 16, 2017 11:32 am

An old timer once recommended pressures in the high 30's. The first time I used them, around 38 as I remember, the car felt awful, twitching and darting. The car was a beast!!
It felt slow. BUT, Lap times were down by over a second!

Your results may vary but low to mid 30's are a good starting place.

A tire temperature gauge and a stop watch will tell you what you need for the track and can also give you a good idea of what you need in straight line street driving. There are many articles on line about how to use a tire temp gauge.

Use the gauge with precision. Don't read one inch from the edge on one side and three quarters inch on the other.

Eric
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PostPost by: Jago » Mon Jan 16, 2017 1:28 pm

Thanks for the advice, I will get hod of a tire temp guage as you suggest.

Regards

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PostPost by: 661 » Mon Jan 16, 2017 5:27 pm

Interesting.
I used to use the 48s on the Exige until swapping to Avon ZZRs which I find a better tyre.
The 48's used to go off a bit if they got to 27 and I aimed for 24F 26 R Hot.
This means starting with pressures lower than that (although not too low and bleeding off after the first few laps)
The ZZRs like high 20's but go off much above 31.
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PostPost by: ftsoft » Mon Jan 16, 2017 8:58 pm

I have run around 30psi on the road for 40 years or so. I ran a little higher than Rohan on the track (35). I found my car to be really squirrely at 20 psi.

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