12g295 head

[shivey]

Has anyone put bigger valves in a 295 head eg 15/16 out of a 1275 head ? looks like it could be done.

[philthehill]

shivey
I know were you are coming from but to be absolutely clear - the 940 inlets are 1 & 5/16" OD and the exhausts are 1 & 5/32" OD.

You can fit the 940 valves to the 12G295 head but it is a lot of work and expense for little gain. The 12G295 head in standard form breathes very well.

Phil

[shivey]

Thanks Phil,the valves have been recut and look like they are sitting a bit low in the head,the seats in the head have been cut as well.i've ordered 4 new inlet valves from Moss but I sat an 1.5/16 valve in the head and it looks in a better position...I'll take better photos...

[shivey]

some more pictures with standard valve and larger valve

[philthehill]

That larger valve certainly does sit better on the valve seat.
In that case I would fit the larger 940 valves.
Just make sure that the overall height of the valves are the same. Some 1275cc engines had shorter valve stems.
Phil

[shivey]

my only other option is to have inserts fitted,i'll see what the new standard valves are like in the head before I make a choice...they are the same length,thanks for you opinion Phil..