Now I have a question about disk brake conversion. My 66 has already been converted to a dual MC and valve. I just purchased the right stuff front disk conversion kit without a new MC. Do you think I will have the same issue?
I would say to run the part number on your MC, and verify the bore size.
The mere presence of "calipers" doesnt necessitate the large bore MC, it's the count and size of the pistons in the caliper, that matter.
Look at it this way, a 300 cui V12, has more cylinders, but less volume than a 455 cui V8.
Likewise, Single piston calipers, with 2.5" pistons, would have more volume than dual piston calipers with 1" pistons.
As I mentioned earlier, it's probably a pain to get the part numbers for your calipers and MC, and then research the two to determine their volume... However... if you don't do this when building your brake system, then it's like buying a carb, without knowing how many cubic inches your engine is... and who would do that?
It's actually quite comical that no one would buy a 400 cfm carb for their 455, but no one sees an issue using the wrong MC to try and stop their car... and BTW, I've sure been guilty of it.
That being said, there's are enough people on the web who have already done what your doing, so I think you can likely skip the intense tech research, so long as you know what you have. If you're going to use the giant, single piston, 67-70 calipers, then a large bore is probably the ticket.
But at the end of the day, only you can do the math.
