The V8 Owners Forum -

the numbers on the rear of the block by the bellhousing are:
10.5 - 1 cr
84006527B
i would like to know a bit more about what i have
thanks mark

Rover P5 or P6 early 3.5, non stiff block with rope main seal

is the old 3.5 v8 out of a p5/6 any good its the one with 10.5 cr and the rope type rear main seal
i wont be tuning the nuts off of it(till i get bored)
will prob fit a 390 holley and tubular manifolds
or should i use the 3.9 i am getting(short engine)and use the bits from the 3.5 to make one good engine(if poss)

i am a v6 freak but have been converted to v8

worst part about the p5/6 engine is the heads as they dont flow well at all due to having smaller valves. Best think you could do to this engine is put a set of later heads on it, SD1 or something like that. Anything from 1976 on, see here http://www.v-8.org.uk/forum/viewtopic.php?t=133. Other than that the front cover has the older oil pump on it which isn't the best. You can get a kit to modify it or again you can replace the whole front for a later one.