Cylinder head cc

[LongBaz463BHP]

I need to get the CR down on my new build and it has been suggested that CC could by increased from 28 to 33. However that doesn't bring it down as far as I would like. What are your thoughts on decompression plates. I know that Neal has successfuly used them on his previous twin turbo, I would need a 1.5mm plate to bring mine down from 9.9 to 8.6
Thanks
Barrie

[ChilliWhizz]

Baz, I'm over the top on CR for FI, I'm running 10.6to 1, so looking at LC pistons which would be prohibitively expensive.... (have HC forged pistons at the mo) I read up a lot on the sandwich plate option, and it seemed to throw up more problems, such as changing the shape of the combustion chamber to something not ideal, affecting the 'squish' area, and obviously raising the manifold height above the block deck although this may not be a problem... I'd be interested to know what thickness of plates you'd need to take a 10.6 down to something ideal for FI, maybe 8.5 or 9.0? Appreciate cylinder bore plays a part here...

Hopefully someone with experience will be along soon..

Chilli