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DAULEY
10-14-2003, 11:10 PM
got a new toy its a 1985 20ft cigarette with a 350hp small block want to get more hp but need to know what the drive can handle tryed to post pixs but am having no luck need some help also any ideas on props
thanks bob

Cuda
10-15-2003, 04:02 AM
I'd say you were at the upper limits of it now.

1996Z15
10-15-2003, 06:58 AM
Regarding the Alphas and Aplha SS's what is the weak point? I can't beleive that nobody has developed a kit that would strengthen these units since they seem to be very common and it's widely known that they aren't the strongest things in the world. I know I can't afford to swap mine out for a Bravo or anything else but I would consider an SS.
Didn't mean to hijack this topic, I just find it hard to believe that we can't strengthen our Aplhas somehow.

Cuda
10-15-2003, 07:05 AM
I believe the upper gears are the weak point. There is a legend of HD gears being available from Merc, but I've yet to see them on any parts list I've seen.

BUIZILLA
10-15-2003, 07:42 AM
Poodle got me my HD Alpha gears in one day's notice. One HD upper gear is identical to the std. gears and uses the stock bearing, the other upper gear has a much beefier bearing hub area and requires a smaller I.D., but same O.D. bearing as stock. There is a Mercruiser bearing kit specifically for the HD gears, which he got me as well.

J

Rootsy
10-15-2003, 07:47 AM
the upper gearset generally and the shaft area where the pinion gear sits (where the spline ends) in the lower gearcase. HD gearsets are available and if you really want to go to extremes i;ve been told that shot peening the gears is supposed to help increase durability and fatique life.

i'm putting roughly 400 ponies and 400 ft-lb of torque through my SS at 5K... i ran 360 - 370 through it all summer without a hiccup.

i HIGHLY advise against hard out of the hole acceleration and airing it out (shock loading)...

Cuda
10-15-2003, 07:51 AM
If you decide to go the Bravo route, I may be interested in the SS.

mattyboy
10-15-2003, 08:31 AM
Bob,
if the 85 20 cig is put together anywhere near the way the 73 20 I'm working on they are heavy boats!ours had a 350hp sbc and a volvo 270 and is a tank if you want a fast one you need a BBC and a bravo we are going for originality so the 350 goes back in and a rebuilt volvo goes back on.

Matty

Forrest
10-15-2003, 10:59 AM
A while back, I had an extra Alpha SS lower-unit gear-case housing that I sold to a guy as a replacement who broke his housing when a gear let-go in the lower unit. He also told me that he had over 450 HP behind it. I can't say for sure that the lower unit is the weak point, but I would guess that it may be one area of weakness. On the other hand, I forget the guy's name at Hydromotive Propellers, but he told me he is running an SS behind a 550 HP blower small-block at 6500 RPM on a light boat with no problems. He did go on to tell me that he applies the power very gently and runs it in smooth water. High torque loads from big power pushing a lot of weight, especially through rough water, I'm sure will break it. I personally would shy away from the SS on a 20' Cig due to the boat's weight and the likelihood that you will be using it in rough water, in favor of something a little more heavy duty - like a Bravo. Also Cuda, Stix Magill did not have very much luck using the SS that I sold him on his Minx. I think that he re-sold that SS and went back to his regular old Alpha. You may wan to contact him for details. One more thing to remember when considering going to an Alpha SS is the upper gear-case housing is no longer available anywhere. Break it and you are SOL. IMO, the SS is the perfect drive for the 16 Donzi and it also works very well on the 18.

Islander
10-15-2003, 05:17 PM
There's an Alpha SS with a Stern Jack on ebay if anyone is interested. Just thought I'd give the heads up.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=26455&item=2437203589

ITTLFLI
10-16-2003, 08:41 AM
I have an SS that I am looking to sell. Bought it for my 22 but never tried it before I sold the boat. $2200 with IMCO drive shower not yet installed.

Byron Scholle
bscholle@intercall.com

DAULEY
10-16-2003, 06:18 PM
boat is 1985 20 ft cigarette. alpha ss drive was new in 1993 it has only 35 hours since it was installed boat runs in the mid 60s with a 23 cleaver at 4500rpms need for more speed any ideas on prop change. engine is 350 small block and was told it has 350 hp only 35hrs on it since it was rebuildt tried to post pixs but they didnt come up i cant figure it out
thanks bob

Budmann
10-16-2003, 06:52 PM
O.K... I'm probubly going to take a lot of heat for myremarks for this, but here go. As most of you know, I worked at the factory back in the late 80's. We put all sorts of horses thru those so called
"weak" alphas. I still have my original drive, and have to date never Quote " Blown the drive." Yes,, it is not as strong as a bravo, however, let's give credit were credit is due.

Before the "Bravo" that's what we did. I have close to 400 hp in my 22, and those of you who have run with me, always tell me how well my boat runs. I don't pamper my drive in any way, shape, or form. If you don't fire wall it out of the hole, then it will stay together. I know too manypeople with bigger boats(Searays, Bayliners, Chapperals, etc. that have the same drive, and alot more weight.

Bottomline... Take care of your drive. I turn a 23 Mirage Plus, which those of you who know boats, know that's alot a prop.

Just use caution coming out of the hole, and you should be O.k.

Cuda
10-16-2003, 07:23 PM
They will also last longer if you keep drive oil instead of sea water in them. :)

Stix Magill
10-16-2003, 08:21 PM
Dauley and Forrest,

I have my Alpha SS for sale (see the parts for sale area). It didn't do well for me and my Minx, but I didn't try any other props. My main reason for selling is that I have a baby boy on the way! :)
Scott Smith

smoothie
10-17-2003, 06:51 PM
DAULEY:
got a new toy its a 1985 20ft cigarette with a 350hp small block want to get more hp but need to know what the drive can handle tryed to post pixs but am having no luck need some help also any ideas on props
thanks bob Bob,I was out of town this week but I did receive your e-mail with no attachments(pics).you may want to try sending one pic at a time,file may have been to large.Would very much like to see some pics. :cool: as far as props go Im finding that a 4 blade or a 3 blade big ear prop is working the best.