[Joe428]

The reason I ask I installed a fresh 383 and my Th350c (lockup) tranny probably wont hold this est. 500hp long so is more logical to rebuild a good stock th350 non lockup or buy one of those expensive high performance trannys (B&M, TCI, Hughes, ATI etc.)? My future plans are big so I want to do it right the first time.

[SSedan64]

The TH350C can be built up for HiPer use but, the Lockup TC's are very heavy and not very efficient = "high slip % @high rpm" for HiPer use.
Depending on how much HP/TQ you're planning on a TH400 may be needed.

Ron Sessions has a very good Book for the TH350.
Also, Jakes TH350 Buildup >> http://www.crankshaftcoalition.com/w...0_Rebuild_tech

TH400 Buildup>> http://www.crankshaftcoalition.com/w...0_Rebuild_tech

[anglia427]

x2 ^ just because its from a well known company dont mean it has the good stuff inside research and do it yourself.plenty of talented people here to help out

[Joe428]

Thanks to both you guys I will pickup a copy of that book. BTW I have several junkyards and can probably find a decent tranny but do you know where to buy a new stock tranny from?