Hi, been looking at various data for yb tuning and have repeatably seen reference to port sizes for 500-600 bhp but no dimensions for the valves that go with this spec to remove the restriction associated with them?. Anybody know?, also what cam combination works well in the band and how much work is required to allow fitment of these cams (presuming that they are going to have significant lift).

 

Nothing wrong with stock valves.

Mark

 

at what point do they become a limiting factor?

 

800hp.

Mark

 

Thats nice to know, thanks a lot. What about suitable cams?

 

Come on John



Just buy my engine

 

Would luv too, but just got past christmas and booked a summer holiday. Bad timing.