Hey Julian,
Thanks for that excellent reply. You listed the part numbers which is great - how about what the #'s would be on the correct A10' dual carb head? One and the same?
Thanks,
Steve
Hi Steve,
Believe me when I say I am no expert in this, all I am going from is personal experience and a small amount of personal research. No second hand info, just checking myself. So I may be wrong on research but I don't think so. Checking and measuring I have done myself so in the instances quoted these are correct for the parts assessed and measured by me.
Here goes ;o)
Ally A7 and A10 early RR heads were cast as 67-1102 (part number 67-1101 as you will notice with most BSA parts, casting number is usually 1 digit later than part number)
Some people say that some 67-1105 (casting 67-1106) heads have the "6" stamped in, but I don't believe this. I have seen (been offered) 2 like this and both had modified ports to get to "std" 67-1105 size and you could see that someone had stamped the "6" with different punches so this was either an early factory mod or more probably people passing off the early head as the 1106. However I think you could modify a 1101 to 1105 and see the same power from both.
Trev, Do you mean casting number 1102 or 1106? In the books / papers I have seen the 54/5 RR has part number 67-1101
As I say above though, I think both could be made to do exactly the same job, just one has bigger holes to start with!
My valves are 38.5 Inlet and 35 Exhaust
Interesting comments.
Julian