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-   -   AMC 401 in a boat (https://www.offshoreonly.com/forums/general-q/257183-amc-401-boat.html)

jeffswav 07-04-2011 08:17 PM

Ok, I usually take heat for being honest so here it goes. I am going to tell you what you want to hear, thats what you want right.
That would be a great marine engine, lots of people use them in boats. Marine parts for that engine are easy to find and when you go to sell it everyone will think its cool. It will have a lot more power than any SB or BB chevy could ever dream of and parts will be cheap. Now what do you think I am really trying to say. :angry-smiley-038:

jeffswav 07-04-2011 08:21 PM


Originally Posted by Donziweasel (Post 3444653)
I have a Jeep CJ-5 with a 304 with no oil pressure. Would love to move up to the 401 if your are interested in selling it. I live at 7000 ft in Jackson Hole and it would be down about 21% of it's horsepower, so it wouldn't be overkill for me.

Hell, my 304 has 345 miles on a rebuild, but horrible oil pressure (no, I did not do the build or it would have stellar pressure). Not sure what is up. Might be just a plug or cam bearings. It isn't making any valve train noise though. Interested in a trade even? IS the 401 bored? It was not recommended boring the 401 over .020, unlike the 360 or 304. Mine is a 1976.

Years ago I had a 76 cj7 with the quatratrac, 304v8 with Turbo GM400 trans. It was a lot of fun, upgraded to a Holley 600 4bl carb.

JB33 07-05-2011 06:22 AM


Originally Posted by Donziweasel (Post 3444653)
I have a Jeep CJ-5 with a 304 with no oil pressure. Would love to move up to the 401 if your are interested in selling it. I live at 7000 ft in Jackson Hole and it would be down about 21% of it's horsepower, so it wouldn't be overkill for me.

Hell, my 304 has 345 miles on a rebuild, but horrible oil pressure (no, I did not do the build or it would have stellar pressure). Not sure what is up. Might be just a plug or cam bearings. It isn't making any valve train noise though. Interested in a trade even? IS the 401 bored? It was not recommended boring the 401 over .020, unlike the 360 or 304. Mine is a 1976.


Um No. Sorry to hear about that. I had similar issues with a 360 and never really figured it out. found a donor jeep and just yanked it, but it had 160k. did they rebuild the oil pump correctly? they are weird but not that hard to do. just be careful with the tolerances. Do a search on 401 oiling mods, they have the same timing cover and may be able to give you something to look at.
I have no idea if the block has been bored before. the pistons are 30 over. not uncommon to go that much. I got this just as I described it with a wagoneer, sold that, kept 401:drink:

would a stock 350 crank hold up to 500ftlbs? I will admit that I dont know much about GM stuff. how much power can you get out of a mild 350 build?
I have an extra non Vortec engine for the boat that supposedly still runs but was replaced due to "smoking".

tinman565 07-05-2011 06:37 AM

What drive is on the boat now ? If its an alpha...you won't be putting much torque in front of it. Are you prepared for the cost and labor involved in changing it over to a bravo ? You have to take all of this into consideration. You still haven't told us what your final horsepower hopes are ? You can build all of the power in the world...but the drive can only take so much. This sport is all about money. You can't really cob things together on a boat like you can with an automobile. :drink:

MnFastBoat 07-05-2011 12:15 PM

going off the deep end here,
But if your truly interested look up Panther Marine, used to be Cali, I think they are in Oregon now, or the other way around, http://pantherjet.com/
i used to have a 1979 Jet boat that had an AMC360 in it.
Was an awesome little package until I moved up.
Panther did a lot of amc stuff back in the day, they helped me with parts and such when I rebuilt my 360 to handle nitrious!
It can be done!, But I will say I had over 12 grand into that motor and jet drive alone! 3300 of it was the drive, rest in the motor!
There are some AMC performance parts houses down south somewhere, memory is not that great now. :( Bought a ton of stuff from them.

It can be done, would I? NOPE, GM is much more common and easier to find items for.
Not sure about coupling, but I had an H conncector for the jet drive, I would assume that would not be a feasible option for an outdrive

Good luck, but research and plan ahead!

articfriends 07-05-2011 05:12 PM

If you are intent on doing it maybe you can use some Glenwood manifolds, water cooled exhaust is the real nightmare when putting a non-typical motor in a boat, I don't know a ton about amc's, will Chrysler exhaust fit? I put a Pontiac 455 in my old boat, was alot of work but it was o/k, got alot of looks at the local sand bar. I wouldn't do it today but I enjoy boating more than working on them these days, Smitty

articfriends 07-05-2011 05:30 PM

http://amccars.net/cgi/yabb2/YaBB.pl...8078;start=all
http://www.vintagejetboats.com/forum...hp?topic=569.0
If you search enough you will find some Panther log manifolds or Gray marine manifolds that were used on Jetboats and industrial applications, everything else is nuts and bolts, alot of discussion on the AMC forums on this, Smitty

Donziweasel 07-09-2011 01:44 PM

Found the issue. Bad lifter.

If you do want to trade, obvioulsy it would not be even. My 304 for your 401 plus some cash from me to make it equal.


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