This is sort of a continuation of the prior discussions about balancing the
pistons / rods / reciprocating parts in a motor.

It came up that there were several different styles of rods (and I had known
some of this from topi's old web site which I think is no longer up and I
did't make a copy of it when I could have).

1: B18 style. Light weight but have a flaw that makes them not ideal for high RPMs

2: early B20 style. Light weight and have factory heat treatment, shouldn't be
shot peened

3: late B20 style. Heavy and may be shot peened. Not as strong as #2.

4: B21 style. same as #3


Where into this list do B30 rods fall? If it is a 71 B30 it will have #2 style
rods? What of a 73? A 75 with metric bearings?

I ask because B30s are typically far less stressed, they wind up in salvage yards because they've got dead BW35 transmissions or because they get 8mpg, not
because they've been raced too hard and spun a bearing. Also, 2 motors worth
of B30 rods yields 3 motors worth of B20 rods. And, the pistons are usually
in decent shape as well (on the B30).

chris