what is needed for 390 or 401 to 727?

[AMX factor]

Big factor on which engine I am going to build 390 or 401. What is it going to take to bolt it to my 727 in my 87 GW. Is it just a pilot bushing needing to be removed for the 401 or one added? The 390 is a bit out there as I'm sure nobody has one in there FSJ but figured I'd ask. I've seen adapters for the 401 to a TH400.

[AMX factor]

oOrry I found several old posts on the 401 question anyways.
Maybe some 390 input??

[jeepzilla47]

i had tried to put a 343 in my waggy. the pilot bushing had to be removed. every thing bolted up. you will need a new flex plate for the 401. mine came out of a 72 amc matador. they are only bout 50 bucks from advance auto. not sure on the 390 flex plate.

[Lindel]

really all you need is a flexplate from an AMC passenger car that had a 401 or 390, the cars got the 727 long before the Jeeps did.

[Cecil14]

I'm not sure if they ever used a 727 behind a 390 stock or not...not sure when they ditched the BW auto. Bellhousing should be the same, and I imagine the flexplate should be pretty easy to come by. Pilot bushing would be the only thing I would look at. Pull the one out of the 401 crank and compare measurements on both cranks.

Anthony

[Kris]

No 390, or any pre 73 AMC will just bolt to a 727 as the pilot in the crank is too small and the flange is in a different spot.
You will have to find an old factory adapter for the flexplate. This adapter moves the flexplate rearward and gives the 727 torque converter something to index in...
If it is a '70 390, you can just get a later 401 crank and rods, and build it as a 401.
If you are going to a manual, this is a non-issue, you would just need the correct pilot bushing for the earlier crank.

kris.

[jeepzilla47]

or... you can use your handy dandy plasma cutter and remove the bushing. but is kinda tricky, especially when it is in the truck b/c you didnt know bout this awesome web page and the good friends and advice you get!!