bayliner 305 to 400 sbc swap

[v8fieromatt]

Hey guys,

I'm new to this forum and to boating in general, I'm an auto mechanic by trade. What i do know is engines.

So what I've done is bought an 88' bayliner capri that measures right at 18 feet. The 260hp 305 chevy block is cracked from being stored though the winter with water in it. I pretty much hate 305s anyway and I didn't really want to do the average swap of just putting a 350 in it.

I just happen to have most of the parts laying around to make a bad SBC 400.

So my questions go like this. Can the OMC drive handle 425 lb/ft of torque and 325hhp? Will the boat controlable? What about the flywheel? Can I use a stock 400 counterbalanced one in the boat? If not would a balance plate such as this one work with the stock one?

http://cgi.ebay.com/ebaymotors/ws/eB...8403422&rd=1,1


Is there anything I should change while I have the motor out? Is there anything else I should know or consider before starting this engine swap?

Thanks a lot!

-Matt

P.S. How fast do you guys think my boat will go when I get it done?

 

[Bondo]

Re: bayliner 305 to 400 sbc swap

Can the OMC drive handle 425 lb/ft of torque and 325hhp?

Nope,............

 

[whywhyzed]

Re: bayliner 305 to 400 sbc swap

260HP stock 350 is the way to go - the 400 never made a very good boat motor despite it's ability to end the outdrive's life prematurely - all the cooling issues and steam hole issues are realized exponentially when you run straight, rusty old water through them.

It won't go any faster - the 305 went to 4600 rpm. The new engine will be limited to 4600 rpm by the bearings in the outdrive. You can change the prop and get a couple more mph after a 350 goes in.

I would expect 45 to 50mph with a stock 350 with a marine cam - you don't want to go any faster in that hull anyways.

 

[HT32BSX115]

Re: bayliner 305 to 400 sbc swap

The only way you would get any "life" out of the drive would be to put a drive like the one sitting on my floor behind it.

(The 460 was rated at 340hp and a "fair" amount of torque...more than any 350..... My brother ran this engine up to 5000 rpm it's whole life....(which is probably what flattened the cam!)

I considered doing that very thing (building up a stroked 350-400) assuming I could find a suitable transom plate/eng mount for it.

But I was offered a 454 Bravo deal I couldn't refuse...........And now you know the rest of the story......



Good day?