It makes a big difference how you drive. If you do a lot of high-revving
clutch popping, you could probably tear one up with a B18, but a lot of guys
use the M41 in racing. Having used several of both, I consider the M41 in
several ways a better tranny, if not as sturdy, as the M410. You can count
on replacing the bearings on an M410 in 100,000 miles, while in normal use
the M41 will last forever if not abused. (You don't have to abuse the M410,
they get that way through normal driving.)
Also the regular bellhousing supplied with the M410 will NOT fit the B18, B20
or B21 engine. The B30 bellhousing mounting is about an inch bigger.
There were a FEW M410 trannies supplied on the 1800E in one or more years
but they are quite rare, and to me, not desirable. I use the M410 on my
164 because they fit, not because I especially like them.
--
George Downs, The "original" Walrus3, Bartlesville, Oklahoma