BVH Exhaust Valve Size

[Matty!]

Creating a list for the engine builder... Can anyone remember off the top off their heads what size the exhaust valves have to be? I read 31mm but cant work out if that's standard or modded.

Thanks
Matty

[hayesey]

31mm is the size of the valves most used and that you used to be able to buy from jabbasport. 

A few used 33mm golf valves (mk2 8v I think) because they were easy to get hold of.  I've heard stories of them not leaving enough metal between the valve seat and the spark plug hole and causing failures, having never actually seen it myself I couldn't say if they're any more than stories though.

Mine has the 31mm ones in it, has been going strong for 10+ years now with them in.

[polo classic]

Mine has 38/33mm valves, but that requires offset grinded valve guides

Sorg Motorsport and KWL (old school Polo-tuners since the 80's) normally use 37/32 mm valves

[Matty!]

Thanks Gents

Ill relay this info onto the builder, he will know whats best to do! May even get the valves made up worst case.