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Tte531 06-14-2017 01:07 PM

Amc 360 piston swap
Ok i hope some people and clarify for me what im reading regarding 360 builds.

So i have my '83 360 apart for rebuild. I like the idea of having the AMC in the car. So i dont plan to swap it out. I want the engine to be powerful enough to haul a trailer with maybe at max another car on it ovr a short distance. As of now i can haul a bare trailer and it feels like i forgot to install the axles before i pulled it.....

I have edelbrock everything but at the end of the day i only have 140-160 to start with.... So i guess my question revolves around the pistons.

I can mess with the crank but at one point the 360 made what 225hp? id be happy with that. From what i can read the crank never changed BUT the piston design may have. Is that true?

If it is can i swap it out for a flat piston or something like what was used in the early 70's? Doing so to raise the compression a bit from the specified what? 8.25:1? Would that help in my search for SOME power lol

babywag 06-14-2017 01:22 PM

Mikel 06-14-2017 06:00 PM


Tte531 06-14-2017 07:23 PM

Hey thanks for that link. I looked everywhere and that was exactly what i wanted... Guess i should have looked harder. Now i feel like i wasted a thread... However thank you again

FSJunkie 06-14-2017 09:29 PM

I used my Wagoneer with its stock 360 to tow a 7000 pound trailer a couple weeks ago, and I live 6900 feet above sea level where the air is so thin that engines only produce about 75% of the power they do at sea level. My stock 175HP was more like 130HP. It kills low RPM torque the most. Pulling the mountain pass was interesting. It's a 5% grade that peaks at 7200 feet elevation. I held 50 MPH up it in 2nd gear. Most everything else went pretty smoothly. It took me a long time even on a level road to reach 60 MPH from a complete stop: at least 30 seconds, but no more than 60 seconds. But I got there.

So you know it is actually powerful enough to haul a trailer.

If I may say so, it seems to me like the problem here isn't your Jeep, it's you being in a rush to get somewhere. Patience and lowering your standards helps a lot in that regard. Not comparing your old Jeep to the performance of a modern vehicle helps a lot too. Those two things are the key to happiness with an older vehicle, and it's really the cheapest way. Just think of how much you will love your Jeep when you accept those two things. You won't be constantly unhappy and wishing for more. It's like reaching nirvana.

It almost hurts me to burst your bubble, but while the published horsepower figures on the AMC 360 changed quite a bit over the years, the actual power produced at the crankshaft while the engine was actually in the car did not change much.

Heavy_Metal_Thunder_81 06-16-2017 06:34 AM

Gearing also has a lot to do with it. Being an '83 you probably have 3.31 gears at best and possibly even 2.73 gears. Both are hardly ideal for towing.

rocklaurence 06-16-2017 08:01 AM


Originally Posted by babywag

This is a Kool build and I want to do this on one of my trucks.
I tow a lot with my J truck. It has the J20 3.73 axles with 34" tires. Which equals approx' 3.20 gears. So, it is slow when towing and gets bad [9 mpg] milage but it's sooo COOL!

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