2 replies to this topic

[paulk 7364]

Will a copper s head 11 stud large valves 32mm/28mm be ok to put on a 998 engine ?

[mini13]

no,

 

for a start cooper S heads were 35/29mm valves ( early ones had 31mm exhaust),

 

the ports will be too big so it wont run great, especially low down,

 

also the valves overhang the bores, so you'll need to mod the block unless your using a very mild cam.

 

the std 1275 33/29 valve head can work ok, but really it needs to be on a pretty hot engine to make use of the ports,

[paulk 7364]

Thank you for the info cheers