Can the Alpha handle 400 hp reliably?

LiberatorII,
What kind of speed are you getting with the stock power?
As far as the big block Ford goes, 55 is about what a stock setup will do.
A well built SBC stroker will beat that.

A 1987 alpha that has not been rebuilt, NO.
A rebuilt drive with new gears, bearings and shafts, Yes.
Big torque is what breaks drives. Alphas can not handle the 500ftlbs of a BB but can handle 400ftlbs from a SB.
Two things I did to the Alpha on my 1987 Donzi: Drive shower to keep it cool and an add on gear lube reservoir to make sure the drive remains full to the top cap.
Have Fun!

Liberator21: It runs a little over 50mph - I'd like to see it do least 60 which is the main reason for the engine upgrade, other reason is I can't stand a loud engine (TT exhaust) sounding anemically stock - am used to BB w/open headers.

Pat: Thanks for the info, I plan to rebuild the outdrive as well. We'll see how much I remember from my old Mercruiser school days....blow the dust off my old 'Cruiser tools, shim guages (ichh) etc.