Shims & Nitro

[Gattorno]

Shims & Nitro

Hi Boys.

This to been always my question more nitro more shims or contrary.

In my motor 3.5 K&B am using the 70% nitro, that height is the adequate one for the head? ???

this of the height of the head it did not have very in account and my motor does not have no shim, therefore is my question ???

Gatt.

 

[TimD]

Re:Shims & Nitro

Gatt,

What is the clearance between the piston at TDC and the head button?

You need to know this figure before considering any changes.

Tim.

 

[GTR]

Re:Shims & Nitro

Hola Gatt,

If you haven't modded your K&B the head clearance is most likely 0.018thou. You can drop this to 0.008 by taking a little of the top of the liner or the base of the head where it rests on the liner. Should work fine at 0.008 - if it detonates try taking a really sharp modelling knife and chamfer the sharp edge on the combustion bowl. Should stop it. Which head does your motor have short reach hemispherical or long reach double bubble?

GT