Stack Panel Speedo Calibration

[EFA]

Just thoughtI'd let you all know I've just been out in my car with a GPS device to check my guestimate settings for the Stack panel with respect to the speedo calibration (tyre circumference)

 

Have found that despite claims that the tyre dia changes when:

 

a) you have weight on it

b) you change pressures

c) you increase to high speed

 

......all the above theories are wrong for ACB10's

 

The dia on Avons website for a 7/21/13 ACB10 is stated at 526mm factored 3.142 times to circumference gives 1652mm

 

Setting tyre circum in the stack to 1652 gives a perfect speed reading at 30, 70 and 100mph to within 0.5%

 

The accuracy on the GPS device when travelling at 100mph was +/- 13 feet which is pretty small.

 

My readings were taken at 17psi cold.

 

Perhaps we should compile an index of readings for all common typres of tyres fitted to cars with the Stack panel...?

 

Arnie Webb

The Fat Bloke blush.gif in a not so Slow Vauxhall wink.gif

 

See the R500 eater here

See the Le Mans Trip Website here

[Gridgway]

yep great idea. I would do it for the CR500s, but am not GPS enabled.

 

Graham