So the cars with louvered hood went from Jensen to Longbridge where the engine was installed then to DHMC to make it into an M. But if the standard motor is in the car when shipped to DHMC, were they installing the high compression pistons there with the motor still in the car? That means removing the head, carbs, exhaust, oil pan, just to get to the pistons then remove the rods with the pistons and install the high compression ones. Sounds crazy.
Just changing the cam requires draining cooling system and removing radiator, removing distributor(it needed to be changed), removing oil pan and oil pump, removing rocker cover and rockers, removing pushrods, removing intake(it needed to be changed to M-style) and exhaust manifolds to access lifter cover and lifters. Not that much more work(11 head nuts) to pull the head at that point. The head also need to have the valve springs changed. Also, the M had a different, slightly thinner head gasket. Stock was a copper/composition/copper unit. The M gasket was steel/composition/copper.
It
seems it would have been easier to have converted engines ready for installation on the assembly line, but maybe their system just didn't allow for that.
I have read that the techs at DHMC were
supposed to be pulling the engines out for the conversion work, but clearly, someone figured out it would be quicker if done in place. Word was that Donald did not approve of this.