Engine Number

[Chris Taylor <spitfire@worldchat.com>]

I have a 1975 spitfire comm. no. FM30090U
however the engine block is stamped FP55738UE
this number doesn't seem to jibe with the comm.
number according to the books and catalogues I have
Is it possible this was a later model replacement block?

Also I will be in Oshkosh Wisconsin the first week of Aug.
for the airshow. Are there any good parts suppliers in that
area I should check out

Thanks in advance
Chris Taylor
75 spit
Burlington, Ontario