over drive trans

inkjunkie said
http://www.moparts.org/Tech/Archive/auto/28.html
i believe there is some issues with some of the shafts needing oil holes drilled in them. when i spoke with my trans guy about a 518, he suggested getting a gas and a diesel case, apparently the diesel unit has got some better parts in it. valve body choice is somewhat limited for the 518, at least this is what Chris Andrews told me a while back. the electronics adds $$ to it, some controllers are in the $1200-1400 area. i was planning on using a gm4l80e in my car, don't really care about the cutting. but problems are that is an expensive trans, needs a 500-600 bellhousing adapter, the electronic speedometer on the trans would need another $$ adapter to work with my cars speedo, it is about 100 pounds heavier than a 727..

That's why the previous owner of my car went with the 700R4. It's light weight, plentiful and won't cost an arm and a leg to replace. He(Mark is a GM tech that loves MOPARS) has told me also that the trans can handle up to 600 hp in stock form. I've also heard from other sources that the 727 can rob the engine 40 hp just to move the car.
But, the down side is all of the fab work that has to be done to get the trans in there. The original cross member has to be cut. A new cross member has to be fabricated. The drive shaft has to shortened. A $400 adapter plate has to be ordered. A bracket for the TV cable has to be fabricated. Last you have to have a electric speedo as well. Unless you are real good at doing fab work this is not for you.
The OD is nice when you are on the highway however. I have mine switched and normally leave it off when I'm on back roads. When I get on the highway I'll turn the OD on. Cruising at 80 and 85 it's nice to have.