I need to replace my tranny; the synchros are going (high rpm shifts = grinding). I have a few questions about the M46.

Are the internals the same from the late 70s-1991? If not, when/where were the changes made?

I know the P-Type o/d is stronger, but is there a difference in the tranny (my o/d is fine, and is a 91 vintage)?

Are there rebuild sets available anymore (stock would be fine)?

I know the earlier models had iron bellhousings, which is supposedly stronger. Are they that much heavier, and would going to an iron bellhousing be beneficial in any way?

I am weighing my options, and I'm searching for an M90; however, cost-effectiveness is an issue and, well, I'm simply not going to push the car's power much past where it is now (15G @13lbs, v15, 2.5 ipd exhaust). So, basically, a ford or bmw tranny is not on my list. That's why a solid m46 will last me for the years I need this car to last me.

Thanks.

Roguls
New York, USA