FJK

I'm helping a guy with a 700R4 & we were debating the merits of more friction discs in the 3/4 clutch pack. What's the differences between run 8 versus 9? There must be some type of trade off. Another question is the free clearance in the clutch pack. Stock, it's .060-.090", on 4L60's it's .030-.060" & TransGo recommends .015-.025". I can see the smaller the clearance, the faster the clutches apply. However, I would think the plates need some clearance when not applied. I've heard .005" per friction disc is a good rule of thumb. Any comments out there, both theory and/or practical driving experience. For my friend's situation, we're talking hi-perf street, not racing only.

Pro Built Automatics

I use 8 clutches in the 3-4 pack, Borg-Warner Hi-Energy's (.080 thick), then .128 top & bottom pressure plates, .062 snap ring, use .060 or .080 steels to arrive at about .040 clearence. If you use the Kolene steels, "polish" them with 600 grit or 1000 grit in direction of rotation only, just enough to remove the rough surface. The Kolene is .005-.006 deep, you're taking only .0005 off at most. Alto says that in the near future there should be "mirror finish" steels available. This what I do to all my Performance buildups. If you are going to road race this unit I would install 7 clutches and the thickest steels possible for better heat dissipatation, due to the 2-3 & 3-2 shift cycling. I hope this helps?