race type exhaust

[steve traynor]

hi can anybody supply me with sketch's/dimension of the part of exhaust where extractor comes in as the one fitted to kevs is letting exhaust fumes etc go back into engine internals instead of what it should be doing.

[Interpol2471]

I would see Dave Brown as his extractor silencer was made by Mr. Madden so should be perfect?

[Wayne]

pm me your email and i will send you a works sketch of a 87 extractor, for the correct race power you need ported housings, 1-1/2 inlets the correct length and timing was 25 degrees with a flywheel thined down to 7mm. the spark plugs were also droped lower. 9 to 1 rotors minimum. Twin plug aro race ported housing gives 6bhp more than a single plug race housing. Amal 36mm smoth bore, or kihlin fcr with remote float chamber, or minuki 40mm cv carbs i am led to beliveOn a std air cooled or commander rotor housings the inlet port is about half that of a race housing, and the gear box wont last long with the above spec at 125bhp + , Though Geof manages it.Regards Wayne