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+--- Thread: Cylinder block dimensions? (/showthread.php?tid=6711)
Cylinder block dimensions? - Henry Harris - 06-10-2021
Any ideas about these two dimensions?
Valves centre to centre and valves centre to bore centre.
Thanks.
RE: Cylinder block dimensions? - Charles P - 06-10-2021
1.125 valve centres (corrected for posterity)
2.00 valves centre to bore centre
RE: Cylinder block dimensions? - Henry Harris - 06-10-2021
Thankyou Charles.
All the original cylinder block dimensions seem to be in units of 1/16 of an inch.
RE: Cylinder block dimensions? - Chris KC - 06-10-2021
2" I agree with; are you sure it's not 1 1/8" between valves? - sorry I have nothing to hand I can measure.
RE: Cylinder block dimensions? - Charles P - 06-10-2021
(06-10-2021, 09:59 PM)The Chris KC Wrote: 2" I agree with; I'd have said 1 1/8" between valves based on cam dims.
Chris, you are quite correct and have proved that I can't divide 2.25 by 2 in my head.
1.125 between valves is correct, and I've corrected my original post to avoid misleading anyone in the future.
And Henry you are quite right. Having measured a number of crankcases on my crankcase machining journey and interpolated the dimensions I came to the conclusion that any that didn't have a bloody good reason for not being an integer or easy imperial fraction were suspect.
Charles
RE: Cylinder block dimensions? - Chris KC - 06-10-2021
I've been through a similar exercise Charles and it's a nightmare - no two parts quite the same and nothing a round figure.
At some point you have to step back and ask yourself what the designer intended...and try to remember it's still a guess!
RE: Cylinder block dimensions? - Charles P - 06-10-2021
(06-10-2021, 10:32 PM)Chris KC Wrote: I've been through a similar exercise Charles and it's a nightmare - no two parts quite the same and nothing a round figure.
At some point you have to step back and ask yourself what the designer intended...and try to remember it's still a guess!
Quite.
What the designer intended didn't always correspond with precision & accuracy of the Austin factory. Crankases are horribly variable, especially in the parallel alignment of the crank and cam
C