the desire to produce the fastest and shortest path to third gear by not using the stock long and deep direct clutch apply circuit has resulted in the fastest and firmest 2/3 shift possible on a th400.also the transmission brake apply and release is guaranteed faster than any other brand on the market,including the griner aluminum valve bodies.make no mistakes here ,im not knocking steves design but weve outdone it with a stock valve body casting as well.features include redesigned 1/2 upshift circuit,transbrake cannot apply in 2nd or third gear by mistakenly pushing the button,aluminum plate with no necessary gaskets eases freshen ups,one piece intermediate and direct clutcd spring assemblies,170 psi fixed line pressure,rear sprag protection thru special release circuit of rear band with check ball orifice,instant reverse and transbrake application thru secondary shuttle valve,and pump modifications especially for turbo buick engines to eliminate crankshaft end play issues associated with excessive line pressure and or converter charge pressures.i guarantee quicker reaction times verses any other valve body,or ill refund your money.