Converting to vortec from old 350

[curtis73]

I'm toying with stepping up to a later roller/one-piece rear block. I know everything about this swap from the automotive end, but I'm new to sterndrives.
I already have a set of vortec heads and an intake, so the top end is ready. I guess I need a new flywheel and coupler? Is that all, or is there more involved?

[tbanzer]

Thats all I could think of.

[blowngas]

oil pan to fit the later model block-----if you go to a hydralic roller cam, the timing chain will have to be changed also, as the bolt circle on the cam is smaller-----just got thru with this same excercise for a truck

[Beer-30]

Don't forget the distributor gear.

[curtis73]

Thanks for all the replies. I'm cool with the engine part.. just not how it mates to the outdrive, and I'm using a Crane cam (probably) which has a cast iron distributor gear pressed on, so its fine to use with the stock dizzy. I have a 2-piece 350 ready to go in with vortec heads that cost me about $1000 to buy and build, but now I'm finding that I could have a reman vortec shortblock delivered to my door for $1550. I'm just weighing the benefits of the roller cam and one-piece seal.
So in my limited research, here is what I may have come up with... Correct me if I'm wrong.
Vortec couplers are the big triangular ones, and earlier couplers were just little cups in the center? Is that right? I found this item (http://bpi.ebasicpower.com/ebinfo.php?pn=GLM11520) that is described as the coupler to use when an early two-piece engine is replaced with a later one-piece engine.

[blowngas]

a new flywheel
I'm not sure but I think the later model one piece rear main seal motors were external balanced-----verify and make sure what yours is before ordering a new flywheel-----I ordered a complete rotating assembly for a 383, and had it done with an internal balance crank------had to order a special made nuetral balance flywheel that had the correct sized bolt circle and flange hole from one of the manufactures

[curtis73]

Will check that out... that might be a problem point... or at least an expensive point