4 cylinder to v8 swap

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ericcarr2000

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I have the opportunity to purchase a 83' Bayliner Trophy boat with trailer. The boat itself pretty much needs complete restoration. It has a volvo penta 4 cylinder engine right now, but the seller states he has a 302 that he was going to put in it. He is willing to sell the package, boat, trailer and the 302 motor for $600.00. Does this sound like a good deal, should I pass on this one, are there any gotchas with these. To date, all of my experience are with Mercruiser engines and alpha one outdrives...
Any helpfull information would be greately appreciated.
What would I need to do to complete the engine swap?
 

Bondo

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Re: 4 cylinder to v8 swap

What would I need to do to complete the engine swap?

Ayuh,... A different motor bed, a different transom assembly, 'n a different drive...
 

ericcarr2000

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Re: 4 cylinder to v8 swap

So you cant just do some stringer modifications to accomodate the v-8?
 

Don S

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Re: 4 cylinder to v8 swap

So you cant just do some stringer modifications to accomodate the v-8?

No, you need an exhaust Y for the V8, unless you use through hull exhaust, and you will also need to change the gear ratio in the drive.
To make matters worse, the Ford engine had better be completely dressed with working flywheel cover, exhaust, marine starter, alt., distributor, carb, fuel pump, raw water pump etc. as nothing is available from Volvo for the Ford engines, and almost as bad with aftermarket parts.

For 600 bucks you can find a better deal than that one.
 

billbayliner

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Re: 4 cylinder to v8 swap

I have a friend who has done several of these swaps and we have talked about this several times.
Here is the deal.
You have a single exhaust relief transoms shield.
You'll need an AQ 200B or 225B exhaust Y pipe to fit the single exhaust relief transom shield.
There is also a Ford Y pipe that is single relief. It will hard to find one but they are on e-bay some times.

Volvo Penta did use the Ford engine.
There are very few course spline 1 pc flywheel covers for the Ford.
There's a Ford 1 pc flywheel cover on e-bay this morning.
Here is the e-bay link
http://www.ebay.com/itm/Volvo-Penta...406883&pt=Boat_Parts_Accessories_Gear&vxp=mtr
He says it's course spline. Yours may be fine spline, but the yoke can be changed.
$(KGrHqJ,!pgE7Bcvh2mHBO+O(nnKBg~~60_12.JPG


This one is the single bearing PDS with a pilot nose and needs a bronze crankshaft bushing installed.
With this one the PDS bearing can be changed without pulling the engine.
I don't think that the drive coupler splines are borg warner, but that gives you an idea of what you would be looking for.



You can also go Borg Warner to V/P PDS adapter housing and get to the transom shield hook up.
The Ford B/W flywheel cover will be similar to this but without the mounts
FMWVDC70A.JPG


Here is the AQ 200/225B with the B/W V/P PDS adapter housing.
This is also one of the 3" Y pipes that may work with 3" exhaust.
images


Here is an example of the Borg Warner flywheel cover and a Donzi or Holman Moody style adapter housing.
This was on iBoats from an old thread.
This puts the engine forward by about 3". Wtih Volvo Penta's OEM adapter, the dimension stays the same.

351.bmp






Add side motor mounts, and change the lower unit to the 1.61:1 ratio.
All of this can be done without making a hoky installation.
 

Don S

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Re: 4 cylinder to v8 swap

Probably a lot more than it's worth.
Without knowing what all you have, what shapes it's in or what the boat looks like, the answer is all but impossible to answer.
But it's going to be more than you can buy a good running boat for.
 

billbayliner

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Re: 4 cylinder to v8 swap

Here is a 3" Ford V-8 single exhaust relief Y pipe on e-bay for $75.00
This one will work with the 4 cylinder transom shield.
http://www.ebay.com/itm/Volvo-Penta...609129&pt=Boat_Parts_Accessories_Gear&vxp=mtr

Here is another Y pipe that fits the single relief transom shield. This one is not bored for the relief and may cause engine load up if trolling for a while.
http://www.ebay.com/itm/aq-270-280-...961857&pt=Boat_Parts_Accessories_Gear&vxp=mtr



I know a man who has made this Y pipe work with the 5.8 Ford. It needs to be modified for the Ford center to center riser dimension. It is the large double relief metric sized Y pipe that needs the V-8 transom shield.
http://www.ebay.com/itm/Volvo-Penta...671737&pt=Boat_Parts_Accessories_Gear&vxp=mtr

Simplest solution is the first one.


Anyone notice anything weird about this B/W PDS adapter housing?

351.bmp
 

sqbtr

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Re: 4 cylinder to v8 swap

Besides that welded up gob holding the bellows snout on?
 

PiratePast40

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Re: 4 cylinder to v8 swap

The snout is on upside down. Wider part goes on the bottom to reduce abrupt flex of the bellows when raising the outdrive.
 

dennis461

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Re: 4 cylinder to v8 swap

The snout is on upside down. Wider part goes on the bottom to reduce abrupt flex of the bellows when raising the outdrive.
I'm glad that one's upside down, I can stop worring about mine

As for $600,
it might be a good deal if the trailer is good shape and the scrap price for engines is up.
In NJ, that engine would be worth $100..

So, offer him $500, scrap the 302, sell parts off the 4-cyl, keep the trailer for a boat in better shape.

Just my opinion...
 

ericcarr2000

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Re: 4 cylinder to v8 swap

So before I even hardly get started on that project, im looking at spending around 5 or 6 hundred bucks just to get the swap complete, and thats not with the outdrive neither????I think im gonna have to pass on this one huh....
Thanks a bunch for all your posts.
Gary
 
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