Re: How to make a meaner Mercruiser 260?
You are correct, but the Bravo came out in 1988. I know Alphas could be had with a 454 in 86-87. and possibly 85. I personally have a Velocity 1987 with a 454 and Alpha SS. The Alpha SS is the same basic design as the Alpha, but most of the parts are different: heavier gears, upper housing is shorter, some of the bearings are different, but the u-joint and input shaft assembly is the same. Most of the seals are the same as a regular Alpha, as is the water pump. The lower gearcase is the CLE (crescent leading edge) that was the same found on the racing outboards. Alpha SS's are quite rare and were major theft targets when parts started getting scarce. As soon as the Bravo became available Merc dropped the Alpha SS. The only advantages I can think of favoring an Alpha SS would be a "possibly" more hydrodynamicly efficient gearcase and a higher X dimension- otherwise I think Bravo is all-around better.
The SS was significantly stronger than a regular Alpha, but not nearly as strong as a Bravo. Mine went 1600 hours on a 330 hp 454 until i swaped in a 430 hp 454- and that has lasted another 200 hours (knock on wood).
If you can find a good condition Alpha SS, it makes a nice swap for a regular Alpha if its affordable: the SS upper gearcase bolts directly to the Alpha bellhousing. If the cost is similar you would be better served with a Bravo.
I have passed up on three alpha ss drives this past year and bought one really nice one for what I would consider a reasonable price. the boat handles a good bit better, gives less bow rise and picked up several miles an hour. I expect to get another few mph out of the swap once It's set up with a higher gear ratio.
It's also pretty easy to get a mild 383 or 400 / 406 to make as much or more torque and horsepower than a stock 454, and you get to use a lot of what you already have. the other nice thing in a smaller boat is that every pound of weight costs speed... a bigblock adds more weight. and a bravo drive a little more.
further a bravo drive has a bit more power loss than an alpha and has more wetted surface area. You will probably lose several mph between an alpha and a bravo. of course if you add the power to make it up, the bravo will hold up without gernading... as long as you take care of it (nothing holds together if you let the lube run low, etc...).
the ss lower is probably a little weaker than a standard alpha and you can put the same hd gears in an alpha upper as you can in an alpha ss.
I thought hard about swapping to a bravo on my one boat and decided it was better (and cheaper) to spend the cash to buy an alpha ss when a good one came along than swap out the transom assembly and spend more money on the drive...