Volvo penta 5.7L GSI to 383 stroker

Mattdunc

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Aloha I own a 2000 four winns 268 vista. Current engine had 509 hours on it. But there is a Crack in the block and head so I need a new engine. It was running before but super rough so I am interested in going the long block route and keep things simple. My specs are as follows: 5.7L 280hp GSI-DPS serial 4110199944 casting number 880 ecm is 5.7TBI drive is a DP-SM with 1.95 duoprop.
I have been doing a lot of research and am interested in upgrading to the 383 stroker engine from usengines.us they claim it would be plug and play by keeping the cam the same but using larger pistons and crankshaft giving me 360hp. I assume I would need to also change my prop size to get full power but will my current out drive support this? Also would I need to reflash my computer? Is it worth the hassle to upgrade to the 383 or just stick with the 5.7L. I have a budget of about 9k including labor and I know that I need bare minimum a long block, new gimbal bearing and u-joints. Any advice would be greatly appreciated.
 

alldodge

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Aloha I own a 2000 four winns 268 vista. Current engine had 509 hours on it. But there is a Crack in the block and head so I need a new engine. It was running before but super rough so I am interested in going the long block route and keep things simple. My specs are as follows: 5.7L 280hp GSI-DPS serial 4110199944 casting number 880 ecm is 5.7TBI drive is a DP-SM with 1.95 duoprop.
I have been doing a lot of research and am interested in upgrading to the 383 stroker engine from usengines.us they claim it would be plug and play by keeping the cam the same but using larger pistons and crankshaft giving me 360hp. I assume I would need to also change my prop size to get full power but will my current out drive support this? Also would I need to reflash my computer? Is it worth the hassle to upgrade to the 383 or just stick with the 5.7L. I have a budget of about 9k including labor and I know that I need bare minimum a long block, new gimbal bearing and u-joints. Any advice would be greatly appreciated.

Howdy and :welcome: to iboats

As a non-VP expert it took me a bit of looking to verify if you have a carb or throttle body. Looking under the 5.7 GSII-A model it looks like your a TBI system. So going from a 350 to a 383 stroker model is plug-n-play for all attachments and harnesses. The bad is you will need to have your computer re-tuned because of the high fuel volume needed.

Your dive should be able to handle the extra torque
 

Bondo

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Ayuh,.... Put an Edlebrock 4bbl. on it, 'n enjoy it,..... 383 could run on a 1409, or a 1410,.....

I like the 1409, as it's sorta a spread bore, with the smaller primaries,...
'n it still feeds Plenty of CFMs after the 2ndaries kick in,....
 

Mattdunc

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Awesome. That is great to hear. I am going to pull the engine tomorrow. Are there anyother reputable engine sellers that I should consider buying from? TC engines in Texas, usengines? What specifically should I ask to get the correct plug and play engine. I am thinking get new risers and starter anything else from old engine that I should just order new. Again it only had 500 hours and was runing prior to my discovery of the blown block and head. What about this quench ratio and dished piston heads I keep reading about?

What are the pros and cons of switching from the current tbi to carb setup? I want to keep this as simple as possible but am willing to spend the extra money to do it right!
 

Tail_Gunner

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Well if you go with that blue print engine or any engine producing more that 350/375 hp it's a much easier path to carb. Tbi is is restricted to about 670 cfm a bit short to run 375 hp along with that tbi is a very aged product factory support is dwindling part resources and becoming hard to find and marine tbi is a very specialized in the fact that it run's on a 30 lb fuel rail (there are some exception"s). From what i have been able to glean the only automotive tbi system to ever use that system was the 94/95 454 and like it or not that is where all the part's are sourced from both injectors and fuel pressure regulator's.

Carb's make it very simple and cost effective.
 
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Mattdunc

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So I pulled the engine and it ain't looking good. Alternator is froze and escentially I'm not sure what I can salvage off the old engine to resale or scrap to put some cash back in my budget. The outdrive isn't looking to good either. No fluid at all in the outdrive and some rust on dipstick but insides look ok and greasy. The u joints are stuck through the gimbal and today going to have to take a sledge hammer from the inside to knock everything out. I.e. taking everything off of the boat engine housing and outdrive. So within my budget and still considering an upgrade to a bobtail engine would a mercruiser 383 work or maybe all the way up to a 7.4L.

If I keep the the current dp-sm outdrive and get it reconditioned what bobtail engines, probably go carb, would be easiest to install and get this boat floating and runing!
 

Tail_Gunner

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A 383 stroker will give you much better performance than a stk 7.4 unless you build the 7.4 to forged internals and square port heads iconel valves etc etc etc the older 7.4's pretty much built to 330 hp and cast internal's but you will find that out yourself as time goes on...5.7 can be played with big time and not much dough to make them run like a raped ape so to speak...

Are you building one or buying one???
 
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alldodge

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would a mercruiser 383 work or maybe all the way up to a 7.4L.

Your boat weights 6800 pounds dry of there about. The boat is heavy so my guess is the boat never came out up on plane very easy. While the 383 will provide more ponies and does increase torque, it will loose every time to a 7.4 or 8.2. If you want the boat to get up and run, go with the 7.4 or 8.2 and you will love it
 
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