- High quality inlet valves manufactured by G & S Valves - This valve is in a larger head size - 1.855". Probably the largest diameter head inlet valve fitted to SOHC Norton engines, this head would normally only be fitted to racing engines (I think I have one of these fitted in one of my racing methanol heads. Standard Model 30\40 valve stem diameter : 11/32" .
We offer these valves in 3 different valve stem lengths:
0033E: 4.650" Valve Stem Length- These valves already have the collet groove machined and are ready to fit. Note: Norton cammy valves were made in a variety of lengths over the years. This length - 4.650" (one of the most common lengths)
0033F: Blank Stem - these valves have an extra long stem (4.875" overall length), but with no collet grooves cut yet. This is the most flexible length, as it allows you to cut the valves to the correct length for your own engine/cambox combination. However - you will need to cut them to length yourself and machine the cotter groove - we can supply dimensions for doing this as required
0033G: 4.590" Valve Stem Length- These valves already have the collet groove machined and are ready to fit. Note: Norton cammy valves were made in a variety of lengths over the years. This length - 4.590" (one of the most common lengths)
Obviously - when fitting valves this large (which really would only be used on a high spec competition engine), it is very important to slowly turn the engine over with valve timing set as the engine is run, and plasticine fitted to the piston crown - to ensure there is sufficient valve/piston clearance. This should be done slowly at first - in case parts do touch, and be ready to stop turning the engine if you feel resistence!
Please email on sales@racingvincent.co.uk if you want more information on cutting cotter grooves on blank stem valves
