Cadwell Track Day - 10th November 2007

[Pike]

Interesting stuff Stu.
We've struggled all year with them in the wet along with a few others (GG compound too).
I'm wondering now if the spring rates are too much in the rain. Did they build up much pressure?

[duncan]

Stu wouldnt have checked

[Stuart]

Just for you Dunk

Pike......my suspension is very soft, only basic dampers and mildly uprated springs. Also standard anti roll bars. In terms of pressure I start them at 35psi when cold and then set them at a constant 35psi wherever possible. Pete only let me check once in the morning and again in the afternoon. He was too busy coming in refuelling and getting back out there as quick as possible.

Beyond that I see no reason why the Sierra would grip when the Golf would not.

[duncan]

Is that your one stu?

This is mine :thumb:

[Gerry H]

[quote="stuartstaples"]
Just for you Dunk ]

Handbags at dawn then chaps?

[duncan]

My grip problems were massively cured by dropping the tyre pressures from 30 cold to 25 cold - these are Toyo R888s. They simply weren't getting hot in the morning.

That's strange ... raising the pressures when wet/cold is the norm as it is the ultimate pressure when hot that is the important bit. If they can never get hot then the actual pressure after a few laps is what counts.

Mine were 31 hot before lunch which was possibly a little low, they went up to 33 after lunch at the front although the rears never got close to proper tempeature.

Having said that, I suppose these things vary per car and driver preferences - if it works ....

[jdening]

My grip problems were massively cured by dropping the tyre pressures from 30 cold to 25 cold - these are Toyo R888s. They simply weren't getting hot in the morning.

That's strange ... raising the pressures when wet/cold is the norm as it is the ultimate pressure when hot that is the important bit. If they can never get hot then the actual pressure after a few laps is what counts.

Mine were 31 hot before lunch which was possibly a little low, they went up to 33 after lunch at the front although the rears never got close to proper tempeature.

Having said that, I suppose these things vary per car and driver preferences - if it works ....

In fact, it's the asymptotic radius if I recall correctly - which depends on weight and pressure.

From Toyo:

Event Distance - Dry Tarmac
Vehicle Weight 4 laps or more Very short - hillclimbs or maximum 3 laps.
Very Light <800kg> 1400kg 27 - 35 psi 31 - 38 psi

Hot pressure is typically around 5psi more after 4 laps...

So, when I reduced mine to 25 cold (31hot), that would be far more like it for the E30!

J.

[jdening]

http://www.toyo.com.au/Pit%20Lane.htm

[duncan]

A wealth of info there James :thumb:

[jdening]

Interesting stuff Stu.
We've struggled all year with them in the wet along with a few others (GG compound too).
I'm wondering now if the spring rates are too much in the rain. Did they build up much pressure?

What pressures are you running cold?