[Alan Roehrich]

Joe,
The theory is that the grooved plates offer an escape path for fluid when they are being applied. The trade off for that is less surface area. Supposedly the grooved plates will offer faster application, and slightly cooler operation. I most often use the smooth plates, as I like the surface area. Not having a data logger to test with, I cannot say one way or another which plates actually offer a cleaner faster shift. As I said, I prefer the smooth clutches in most applications, when I can get them. I've had the best luck, and the best long term durability, with the Alto Red Eagle clutches and the Kolene treated steels. I know just as many people that prefer the Raybestos Blue Plate clutches, and some also use plain untreated steels with both. Good results can be had with all of them, provided the job is done right. None of them will cure a poorly timed shift, or a serious torque capacity problem. That's about all I can offer you from about 25 years of building automatics. I should probably know a lot more, I wish I did.