Alpha1 3.0L to a V8 Swap

[67Firebird326]

Hi im new and i would like to know if i could swap out my 4cyl for a pontiac 326 V8? i think all i need to make it work is a adaptor to mate with drive right? Also this engine is a 250hp 326 and 333ft-lbs, is this engine to much for the drive? Thanks for any help.

 

[WillyBWright]

Re: Alpha1 3.0L to a V8 Swap

Don't put a car motor in a boat! It won't last if you can. Boat versions are made to operate at redline for hours at a time. Can a car motor do that? Heck no. Car motors rarely see the RPMs that boat motors operate at all the time.

There are also a multitude of parts that are marine-specific. Car motors are pretty well ventilated under the hood. Boat motors are enclosed. That traps fumes and any stray spark from an automotive electical component makes boats inappropriately powered go BOOM!

The drive isn't an issue except fot the gear ratio. They can handle 300Hp. But a 3L has about a 2:1 ratio and a V8 is about 1.5:1.

Most marinized powerplants are GM smallblocks or bigblocks. Not Pontiac, but closer to GMC.

 

[Bondo]

Re: Alpha1 3.0L to a V8 Swap

Ayuh,......

It's the Pontiac that's the Biggest Issue......You Can't buy Manifolds to fit it.....

 

[sabastianunf]

Re: Alpha1 3.0L to a V8 Swap

What are you going to put in the bird? Got any pics of it - has always been on of my favorite cars.

 

[whywhyzed]

Re: Alpha1 3.0L to a V8 Swap

I'm not sure why no one ever put a Pontiac in a boat. It's a Chevy world in marine. OMC used some Buick 225's, 231's V6's and 300 cube V8's, but I've never seen a Pontiac engine on the water therefore as mentioned above, no marine exhaust manifolds exist for them.

 

[jedimaster]

Re: Alpha1 3.0L to a V8 Swap

I have seen a fair number of 225 slant six mopars as well as a few older hemi's

 

[Bondo]

Re: Alpha1 3.0L to a V8 Swap

Chrylser has been Out of the Marine motor business since about 1970........

 

[87baylinercapri]

Re: Alpha1 3.0L to a V8 Swap

im not quite sure about this car motors cant run at high rpms for a long time theory...i build drag cars, and drive em to the events. i run at 3400 rpms all the way to the track for 2 hours...there is no difference, except that the boat engine is camm'd different so it has more low end, my boats "redline" is 4300 rpm, my car's redline is 7 grand, big difference there.

 

[Coors]

Re: Alpha1 3.0L to a V8 Swap

Cruising down the road is almost no-load, compared to the load the prop puts on the boat engine.

 

[jedimaster]

Re: Alpha1 3.0L to a V8 Swap

From what I have read, the main difference, are brass freeze plugs, Head Gasket, Carb overflow, Fuel pump, Starter, alternator, distributor, Flash supprsion filter, camshaft, thermostat, intake/exhauhst manifolds, bell housing and flwheel.

Once you have all that sorted out you should be ok, just don't give me a ride in it.
Basically, yes you can do it, but it will be dangerous, and likely won't last very long, if you don't take all the precautionary measures.