Which parts DON'T interchange 360-401?

[illegalFSJ]

OK, I know the block, crank, rods, harmonic balancer and flywheel are different (right?)
Is this everything, or are there other parts that are 401 specific and that I can't swap over from my 360?
Since my 360 seized, I'm just gonna go straight to a 401, rather than rebuild the 360 block. Besides, I've always wanted a 401. smile.gif
Thanks.

[joe]

Heads, int/exh manifolds etc are all the same. Go for it.

[illegalFSJ]

The part that worries me is trying to find a flywheel for a 401. This would be easy if I had an automatic, but I don't think alot of 401s came from the factory in front of a manual trans. Are they out there, or is this one of those parts that's harder to find than the holy grail?

[tomd]

pistons are different also

[Crazy_Jeepman]

Originally posted by illegalFSJ:
The part that worries me is trying to find a flywheel for a 401. This would be easy if I had an automatic, but I don't think alot of 401s came from the factory in front of a manual trans. Are they out there, or is this one of those parts that's harder to find than the holy grail?Very expensive but are out there. You can have the 360 Flywheel balanced to the 401 rotating assembly, cheaper than buying the 401 flywheel

[joe]

All the 401's in FSJ's had the TH400 behind them so you'll need to find a flywheel from a Rambler model that had the 401/manual option. How hard is this to find I don't know.

[illegalFSJ]

I'm intertested in the idea of of having the 360 flywheel balanced to the 401. How is this done, what's involved, is this done by a machine shop, and how much does that usually cost?
Thanks!

[Chero77]

401s were offered with manuals in '71-'74 Javelins, Rebels, and maybe others. They do exist and occasionally show up on EBAY. An AMC specialty parts supplier might have one. My guess is if you want it quick, you will need to rebalance a 360 flywheel. Don't know how much this costs, but I am sure many engine shops can do it.

[Retro93]

I think 4WD Hardware sells new 401 flywheels for around $200. smile.gif

[Wesdog]

Ask the guys on the AMC forum: http://www.amcforum.net/forums/

Also, Mondelo's may have an aftermarket one available: http://www.mondellotwister.com/CatTechAcc.htm

If it were me I would just have the engine externally balanced with the 360 flywheel. It has to be balanced anyway during the rebuild whether you use a 360 or 401 flywheel. The AMC forum guys can provide a better detailed response.

[Al Johnson]

When I rebuilt my 360 I had the shop balance it, and they did the flywheel at the same time, no extra charge. Somebody on e-bay sold me an unknown (but not 360) flywheel, and the shop took quite a bit of metal off it to get it balanced. (Balancing was $150 at my shop, BTW.) It has to be done while you are rebuilding, because they need the parts separate and loose. Can't be done in the block.

[illegalFSJ]

Thanks for all the leads! Now I can try to figure out what I'm doing.

[Crazy_Jeepman]

Since you are building one from the ground up I would opt for the rebalance of the 360 Flywheel to the 401 rotating assembly. Good luck