chapp-sx

Does anyone know how much more power the heavy duty gear sets and bearings can take in an alpha one? Going to swap out the stock 5.7 260 hp for a GMPP CT350 350hp 390tq motor. The drive needs a going through anyways and I'm on a limited budget so I cant swap to a bravo and a big block. Going to attempt most of the work myself, any input or advise would be greatly appreciated.

ChristianGott

Your regular Alphas should handle that. If in doubt, have them rebuilt and shimmed precisely. I had 330 hp on a 24 and it held up fine. My twins have 600 hours behind my 350 mags.

zdek

I'm running alphas behind my LT1's that are making 425hp. I'm way easy out on them of the hole and chop the throttles if I catch some air. I'm also running Imco shorties - the drives are great, and the oil comes out clean. 250ish problem free hours.

Get some drive showers if you are going to be running fast for extended periods!

mountainmadness

you will be fine with that stock stuff. I ran a 540+ hp SBC through a stock alpha for last 3 years, then I found a alpha SS drive and switched over to that.

chapp-sx

Thanks for the vote of confidence, I was planning on putting a drive shower on anyways. How is it rebuilding an alpha, I have a shop manual and have looked it over many times. I have a neighbor that has rebuilt them for his fishing buddies, he showed me how to change the water pump in mine last summer, but he is such a hammer machanic and rushes through everything with dirty hands and dirty work benches, if he showed me how to do it I'd have to take it apart and do it over cause I'm anal about rebuilding in a clean environment. I'm good with gear boxes, I rebuild servo driven rack and pinion type robotics at work and various other types of mechanical and hydraulic equipment. I'm just gunshy about something that could leave me and my family stranded miles from shore. Would like to learn though. Should also go through my bellows too, I ran it pretty hot when my water pump went out last season. Thanks again for the responses.

pullmytrigger

IMCO makes shorties for alpha's??......cool,I'll have to check that out!!......post pic's!

pullmytrigger

Traviss - did you pick up any speed changing to the SS??

mountainmadness

I can't really say, I never had a gps on it, i was still trying different props at the time, with the SS drive the boat tends to run with less trim and the boat runs more level, my boat does not like to run level, you would get on the trottle and it would drive the bow down and bow steer, scary in my boat. I found a laser prop I was using and that finally got the bow up out of the water where it ran alot more comfortable. I only used the boat 3-4 days this year, ohh well I guess. looking for someone to buy it hopefully, but with this economy up here nobody is buying anything

Ryan00TJ

I don't see your stock Alpha 1 having any trouble with that power. Add a drive shower, Merc HP gear oil, and no aggressive coming on plane from a dead stop. It should be fine. I've ran 4 350-400hp 355's thru a stock Gen 1 1991 Alpha. I have two Alpha 1 both with hydro nosecones, updated 13-21 teeth lower gears, and HD upper gears. They will be going in front of my new 475hp 385ci SBC this summer.

I've rebuilt alot of Alpha's and they are easy as long as you have the right specialized tools. I've even made some homemade tools that even make it easier to pull and install the bearing races. Without the right tools there is no way to do it right. To properly assemble an Alpha 1 your going to need $750-1000 worth of tools. You need shimming tools for the driven gear, drive gear, lower pinion gear, pinion nut install tool, mandrels and bearing pullers, slide hammer, etc... along with basic mechanical tools. A hyd press is also a wonderful thing.

It sounds like you have the background experience to perform the task. My advice is to get the Merc #6 Alpha 1 drive manual and go over the procedure and right down the tools needed. Once that's done you might be over what it would cost to have it professionaly done.

BTW those #6 manuals go on ebay all the time for $10-20. If you get into it and have any questions feel free to ask me.

glassdave

I would like some info on this as well.

I've got an Alpha question as well for you guys. I had great luck with them on my Scorpion with 320hp smallblocks. Any thoughts on which one is the strongest of the Alpha series? I have run Gen ones and even MR's. Even though it is an older piece the MR is a pretty durable unit as well.