88 omc 5.7 motor swap

[jeicher]

Hey guys,

I’ve built a 350 gm motor to swap out m omc 5.7.
I’m at the stage of completing and ready to stab a distributor. I’d like to just go the HEI route as I have new ones on the shelf. I’ve read of people having different issues time after time. What I want to know is if I go HEI what else needs changed?

Boat is an 88’ four winns
Okc 5.7l
Cobra stern drive live

 

[matt167]

You will want good life vests and burn cream for later. If you survive the gasoline explosion…. NO bs either. An HEI is not ignition protected. Hopefully your built 350 is built to marine specs as well or you could pull water in with the wrong camshaft

 

[Bondo]

Hey guys,

I’ve built a 350 gm motor to swap out m omc 5.7.
I’m at the stage of completing and ready to stab a distributor. I’d like to just go the HEI route as I have new ones on the shelf. I’ve read of people having different issues time after time. What I want to know is if I go HEI what else needs changed?

Boat is an 88’ four winns
Okc 5.7l
Cobra stern drive live

Ayuh,..... Welcome Aboard,...... As noted, the automotive Hei is a no-go, as it's not ignition protected,......
Dui makes a Hei that is,.....
The go-to boat replacement ignition is the Delco Voyager system, which is reasonably inexpensive,......

 

[Scott Danforth]

agree, no automotive ignition stuff...

 

[matt167]

Ayuh,..... Welcome Aboard,...... As noted, the automotive Hei is a no-go, as it's not ignition protected,......
Dui makes a Hei that is,.....
The go-to boat replacement ignition is the Delco Voyager system, which is reasonably inexpensive,......

I had no clue Davis built marine HEI. I can only imagine what they cost. I know what his stuff cost 10 years ago when I was looking into one for a 200 straight 6 Ford

 

[jeicher]

Bondo do you have a link or more info I’m on that voyager? Thanks

 

[Bondo]

Bondo do you have a link or more info I’m on that voyager? Thanks

Ayuh,.... https://duckduckgo.com/?q=delco+voyager+ignition+system&ia=web

 

[Scott06]

I had no clue Davis built marine HEI. I can only imagine what they cost. I know what his stuff cost 10 years ago when I was looking into one for a 200 straight 6 Ford

$339

GM Marine DUI – Performance Distributors

performancedistributors.com

I'd do the Delco est as that is pretty standard in marine use and used by OEMS

 

[jeicher]

Ok delco est ignition system ordered. Now to exhaust. Should I replace all the manifolds and risers or just inspect, replace gaskets, and reuse?

 

[jimmbo]

Just curious, what are you using for the Fuel System, the Alternator and Starter, the Water Pump, even the Core Plugs?

 

[Lou C]

Are you in a freshwater region? If so your manifolds & elbows may be re-usable.
I still have my original Prestolite points distributor. If you go with Delco EST, or other electronic distributor, you're going have to change the original ESA module, if you still have it. CDI Electronics makes ESA modules that will work with electronic distributors.