As pointed out to me by our own Andy Mace, I was in err. . and in the
quest to provide accurate information I'll correct my previous post!
That'll teach me to recall from memory! The actual siamesing of the
cylinders to achieve a possible maximum increase to 1621cc if required was
actually done well before the introduction of the Spitfire and these
engines ('SC' series) were used in all Spitfires. The change to the
revised block and heads with 10 studs instead of the earlier engines 11
studs was done with the introduction of the MKIII 1296 engines-That's where
my memory screwed things up. I was assuming that at that time the
cylinders were siamesed to achieve the increases. So the crank would have
been similar for the entire range as far as spacing for the throws, but
with the introduction of the MK4 the bearings would change to the larger
ones and in 73 the stroke would have lengthened for the 1500. Still for
all practical purposes, the engines for the MK1/2 would be similar, and due
to the revisions in the block and heads with the introduction of the MK3,
the engines in the MK3 thru 1500 would be similar-
Hope that clears things up a little bit.
Thanks to Andy for pointing that out, and saving my face-now I'll go stand
in the corner for a while :-)
Barry Schwartz (San Diego) bschwart@pacbell.net
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