Originally Posted by Gen1dak
The A500 was a lockup unit from day one (1989 model year), but Mopar held out a while on the 518. They had a habit of phasing in upgrades or changes. It wasn't all bad. Those early Mopar-specific lockup units weren't very durable and those wanting the overdrive were happy to grab the 518 and slap a B&M Holeshot converter on it. Man, things sure have changed. When I was a kid you were Hot Snot if you had a Holeshot converter. Nowadays, you never even hear about them.
If I remember right, I think the B&M was the hot ticket for Mopar 727's for a while.