2.3 to 3.8 Conversion

Yes....you read that right.

I was wondering what you guys thought about converting a 1988 2.3 to a 1984 3.8 using a V6 Cobra drive.


Here is the backstory.....I purchased a donor boat with a cracked 1988 4.3 a few weeks back with the intentions of getting a Rapido motor or a donor motor from the salvage yard. After I sold the trailer I was only out $150 for the 4.3 Drive, Wiring Harness, and all the other goodies to do the power upgrade.

Then I remembered tonight that Dad had something in his backyard that Mom wants gone.....a super low hour 1984 Stringer with a 3.8 in it. The drive is blown and the old boat just sits anymore since they got the pontoon last year.


I did a ton of research on the interchangeability of these 2 motors and from what I can tell this swap is possible. I should be able to use my 4 barrel carb and manifold too! I was a little concerned about the ESA but the part numbers are the same for both motors. The only thing I think I will have to purchase for this swap would be an engine coupler for the 2 piece rear main seal. Manifolds and all gaskets should work.

Have I missed anything?


Long story short....Rapido 4.3 $1600+, Rebuilt Locally $2000+, Junkyard conversion $500+ and who knows how long it will last, Pops old 3.8 FREE!



Here's Some Pics of My Old VIP that I hope to do this too. My father bought this boat brand new in 1988 and we were at the lake 4 times a week during the summer until I headed to college in the mid 90's. Like almost all VIP's everything wood rotted and Dad gave up on her. He said if I could fix it I could have it. I lurked on here for a year or so in the restoration forum and did a cap off resto down to the bare hull with a few bumps in the road along the way. I've had it on the water for a summer now and she runs like a top. She even still gets looks sometimes. (Usually of disbelief that a VIP that old still floats:facepalm:.....)




Thanks for such a great resource for us do it yourself boat folks.

I look forward to hearing what you guys think of this hybrid of a project!

Re: 2.3 to 3.8 Conversion

The 88 2.3 the inner transom parts aren't setup for a V-6 motor.
You have the v-6 drive?
The 2.3 lower is a bit lite for a V-6 will work,just lite.
The upper gear housing is the same 21:21

Re: 2.3 to 3.8 Conversion

As long as the 3.8 is a runner - no cracks and has it's original distributor, you should be ok to replace the 4.3 with it and use the 4.3 setup.

The only drawback to the 3.8 is that you'll be stuck with points ignition forever, but that's minor.
I'm not sure what year the intake bolt pattern changed on the chev v6, but if the 4.3 and 3.8 have the same number of bolts, the manifold will swap. The 4.3 ratio drive will work fine with the 3.8 4 barrel.

Re: 2.3 to 3.8 Conversion

jerryjerry05 said:

The 88 2.3 the inner transom parts aren't setup for a V-6 motor.
You have the v-6 drive?
The 2.3 lower is a bit lite for a V-6 will work,just lite.
The upper gear housing is the same 21:21

Click to expand...

I have a 4.3 drive and all of the inner transom parts for the V6. It came with the donor boat. Thanks for your input Jerry!

Re: 2.3 to 3.8 Conversion

Howard Sterndrive said:

As long as the 3.8 is a runner - no cracks and has it's original distributor, you should be ok to replace the 4.3 with it and use the 4.3 setup.

The only drawback to the 3.8 is that you'll be stuck with points ignition forever, but that's minor.
I'm not sure what year the intake bolt pattern changed on the chev v6, but if the 4.3 and 3.8 have the same number of bolts, the manifold will swap. The 4.3 ratio drive will work fine with the 3.8 4 barrel.

Click to expand...

The 3.8 should be fine. My old 2.3 sat for 10 years and with a little TLC started right up. Dad was always a stickler about draining the blocks on the boats for Winter. The boat with the 3.8 actually sat in the garage up until this year. The points ignition doesn't bother me. My 2.3 is still running points. Manifolds are both 12 bolt. Thanks for responding Howard!

Re: 2.3 to 3.8 Conversion

Well the 3.8 was cracked after all. I picked up a 4.3 out of a '97 Blazer and am having it rebuilt locally. Vortec heads and a 4bbl carb should be fun in an 1100 pound boat. Just waiting on my electric fuel pump kit and 8 bolt manifold to arrive. Thanks again for the input.

Re: 2.3 to 3.8 Conversion

you'll need a marine distributor too.
OR!:
You can put the 4.3 Pertronix kit for prestolite distributors into the 3.8 marine dizzy and you'll kill 2 birds with 1 stone -
1. converting points to electronic and 2. converting the semi even firing pattern of the 3.8 dizzy to the even needs of the 4.3