two outdrives to one

[1Zorro1]

Any thoughts on rebuilding a transom that has two key holes and making it a single? Carver Santego 27 had two 171 siezed VPs, will have one 383 vortec same horsepower near 400 running on an SP 2:15 outdrive. Built this motor two years ago pushed my Sunray 26 47mph gps. Change the entire width of plywood? Can i do a two sectional overlap? Have to move the stringers-engine mount beds outboard so they have to come out, will fab new ones wider apart and low enough to accommodate the big motor into the center. No this is not my first major refit. lol Will take some lower res. images tomorrow to show you the progress. Thoughts?

 

[pckeen]

Re: two outdrives to one

Can't see why not, provided you replace the entire transom, properly support it. I wouldn't consider doing this without putting in a completely new transom.

 

[pckeen]

Re: two outdrives to one

Can't see why not, provided you replace the entire transom, properly support it. I wouldn't consider doing this without putting in a completely new transom. Where abouts in Northern Ontario are you, zorro?

 

[zool]

Re: two outdrives to one

The 2:15 ratio drive gears wont work with with the 8 cyl engine...need a 1:61 ratio lower unit to use the drives that came off the aq171's......im doing a similar swap, but replacing two 171's with two 5.7s.....I already did a lap on my transom, came out fine...

You will also need a different y pipe and flywheel cover...

check out the link in my signature towards the beginning..

 

[1Zorro1]

Re: two outdrives to one

The 2:15 ratio drive gears wont work with with the 8 cyl engine...need a 1:61 ratio lower unit to use the drives that came off the aq171's......im doing a similar swap, but replacing two 171's with two 5.7s.....I already did a lap on my transom, came out fine...

You will also need a different y pipe and flywheel cover...

check out the link in my signature towards the beginning..

Thanks for your reply. The motor has already been in the Sunray connected to a 275 VP 2:15 ratio. Worked fine with a 21 pitch prop. Motor was cammed for 5000 rpm, worked bang on. I am using the "bellhousing from the 275 already on the stroker it mates up fine to the universal. For the y pipe i am thinking through transom pipes. Do you think i'm okay? did i miss something?

 

[1Zorro1]

Re: two outdrives to one

Can't see why not, provided you replace the entire transom, properly support it. I wouldn't consider doing this without putting in a completely new transom. Where abouts in Northern Ontario are you, zorro?

I'm from the Lakehead, you?

 

[zool]

Re: two outdrives to one

Ok, you have an aq275 drive, not an SP series....they both call for 1:61:1 but if you got it to work by propping it, so be it..its way out of spec tho..not sure on longevity with that setup, but I hear its more doable, with the bigger hulls.

Thru hull would solve the exhaust issue, if you can find the right y pipe and run it thru the drive for a quieter operation.

heres an operators manual for the 275

ftp://vk.od.ua/34124.pdf

 

[1Zorro1]

Re: two outdrives to one

Ok, you have an aq275 drive, not an SP series....they both call for 1:61:1 but if you got it to work by propping it, so be it..its way out of spec tho..not sure on longevity with that setup, but I hear its more doable, with the bigger hulls.

Thru hull would solve the exhaust issue, if you can find the right y pipe and run it thru the drive for a quieter operation.

heres an operators manual for the 275

ftp://vk.od.ua/34124.pdf

Thanks a ton or the manual. At least i have two outdrives lol. Was told the VP's are tough, the same gearsets (other than ratio,) and bearings go into the AQ drives for 454 as do for the 4 bangers. The last boat had an alpha-one swapped it out as the stroker had more power than the merc was rated for. P.S. the Carver is 8800 lbs. lol.

 

[zool]

Re: two outdrives to one

They use a hypoid gear set, tough as nails, and easier to work on than mercs, imo...looking forward to some pics

You will have an easier time with the new keyhole, not having to deal with an inner plate and gimble...the tolerances aren't tight at all..

 

[Scott Danforth]

Re: two outdrives to one

Why not go with twin SBC's? your carver came with twin V6 mercruisers, the twin AQ's and a few other options.

 

[1Zorro1]

Re: two outdrives to one

Why not go with twin SBC's? your carver came with twin V6 mercruisers, the twin AQ's and a few other options.

Off hand my reasons for going single engine are... simplicity of maintenance, fuel economy (i like to run just off idle the majority of the time), I now have a ton of spare parts (two drives, transom plates etc, hydraulics, pumps, and all the electrics), I have the near new 383 motor i built specifically for torque, and i hate small motors lol. Think that engine bay will look much better with one big motor rather than two shoehorned in nice to work in. 100 gallon fuel capacity for one motor, i like that as well.

 

[Scott Danforth]

Re: two outdrives to one

I was thinking two 383's myself. However my friends 27' Carver Montego only has only a single motor. it is much easier to work in there with a single motor.

the down side of a single is if you have issues, youre coming back on a tow vs a remaining motor.

 

[1Zorro1]

Re: two outdrives to one

I was thinking two 383's myself. However my friends 27' Carver Montego only has only a single motor. it is much easier to work in there with a single motor.

the down side of a single is if you have issues, youre coming back on a tow vs a remaining motor.

Lol the thought did cross my mind about two 383s. 800 HPs or there about is tempting, but fuel costs being what they are and the extended trips on Superior planed i think having a kicker bracket and a twenty outboard will suit my needs.

 

[bigdirty]

Re: two outdrives to one

Lol the thought did cross my mind about two 383s. 800 HPs or there about is tempting, but fuel costs being what they are and the extended trips on Superior planed i think having a kicker bracket and a twenty outboard will suit my needs.

Now THAT would be some kinda fun! :lol: but you would be passing everything but the fuel docks.. I get the single motor being easier to work around too, but in a boat that big I just think twins = more maneuverability.. You will loose some going to a single, although if you know what you are doing, a single is not 'that' hard to operate at the dock/around tight places. If it was my project, I'd likely look for some newer 4.3 V6 mercs and bravo drives to pop in, but seeing as you have the motor already, and the volvo drives, it sounds like the more 'economical' choice.

 

[1Zorro1]

Re: two outdrives to one

A bit snowy at the moment... Pic one the stroker in back of my 454 propane GMC waiting... Two shows the beds that need to be moved down and outboard. The tanks, controls and misc. items are now removed or tucked away 50 gallons of fuel drained. Three shows the mock-up where i think the outdrive will sit marked on the outside. Four is of the Sunray with the 383 installed. I plan on boarding and glassing the stringer to the chine direction tapering out to the dead-rise under the tanks leveling the work platorm and further reinforcing the transom and stringers similar to pic four.

 

[1Zorro1]

Re: two outdrives to one

Hunkering down for another snow storm lots still on the ground too. Will be cutting in beginning of the month.

 

[pckeen]

Re: two outdrives to one

I'm from the Lakehead, you?

Dryden

 

[1Zorro1]

Re: two outdrives to one

Some advice on the filling of the old keyholes? I plan on filling the glass after the new plywood is installed. Feather out a normal large area back from the opening using the progressively smaller layers of cloth to fill out according to thickness of what is there already, then applying gel coat. Any thoughts or concerns?? Will be using polyester resins through-out the process with mat and rove layers.

 

[jbcurt00]

Re: two outdrives to one

Feather out a normal large area back from the opening using the progressively LARGER layers of cloth to fill out according to thickness of what is there already, then applying gel coat.

Fixed it for you ^^^

Like this:

 

[1Zorro1]

Re: two outdrives to one

Thanks, my instinct was to do as you say but read somewhere to start with a wider layer in mat. Much appreciate your time. Will send pics when it gets under way.