I HAVE A 68 AMC JAVELIN THAT USED TO HAVE A 258 6 CYNLINDER W/ A THREE SPEED ON THE COLUMN . I BOUGHT A  401 FROM A 76 WAGGONEER THEY SOLD IT TO ME AND I BOUGHT AS A 360 BUT THE CASTING ON THE SIDE SAYS 401 .. THE PROBLEM IS MY BELL HOUSING IS TO SMALL FOR THE 401 I THOUGHT THEY WERE THE SAME BLOCK AS A 360 IS IT ? AND WHAT KIND OF TRANNY CAN I LOOK FOR AND WHAT KIND OF VEHICLE HAS WHAT I NEED . AT THIS POINT THE MOTOR IS JUST WAITING FOR THE RIGHT TRANNY WEATHER IT BE A AUTOMATIC OR MANUAL MAKES NO DIFFERENCE TO ME . THE BODY WORK IS COMPLETE AND READY FOR PAINT BUT THE WHOLE PROJECT HAS BEEN PUT ON HOLD . I NEED HELP BAD OR THE FIANCE IS GOING TO MAKE ME SELL IT . I HAVE A 727 TORQUEFLITE FROM A 1983 DODGE VAN THAT IS BOLTED TO A DODGE 318 COULD I USE THIS ?I HAVE SEEN THE ADAPTER PLATES TO MATE THE MOTOR W/ A CHEVY AUTO BUT WOULD LIKE TO STAY W/ A AMC TRANNY .. I LOVE THIS CAR AND MY DAD HAS ALWAYS HAD A 68 AMX W/ A  343 AND FOR SPEED SO I HAVE ALWAYS ADMIRED THE LITTLE CARS AND HAVE ALWAYS WANTED ONE . I BOUGHT THIS JAVELIN AND DREAM OF CRUISING IT TO SHOWS UNTIL ONE OF MY BOYS IS READY TO DRIVE . WHAT KIND OF TRANNY IS IN MY DADS CAR ANY IDEA ? WELL THANK YOU FOR YOUR TIME AND ANY INFO YOU CAN PASS MY WAY .                          QUENTIN                                                                                               

There are tons of AMC people out there that are more knowledgeable than I am...but here is what I do know for sure.  All second and third generation amc v-8 engines have the exact same bell housing pattern.  Second generation v-8's include 290, 343, 390 engines (66,67,68,69,70).  Third generation v-8's include 304, 360, 401...which are slightly stroked versions of the same engines.  There were other slight changes as well between them(heads changed some, deck height change, ignition and distributor systems changed over the years, etc.  The original amc inline six engine bellhousing bolt pattern is NOT interchangeable with all the post 66 v-8s, but AMC decided to change the sixes' pattern to the post 66 v-8 style for interchangeability reasons.  As a 10 year jeep CJ guy, I can tell you with absolute certainty that 70's 258s interchange directly with 304s, 360s, and 401s using the same bellhousing.  I have made plenty of the swaps personally.  I am too lazy to look up the date as to when the six was swapped over to the "newer" bolt pattern, but my recollection is that it was in the late 60's before AMC bought Jeep.  I'll assume that your six has the earlier bellhousing pattern.   

     So don't sweat it.  You will need to keep in mind that their are some mild interchangability issues with using 60's transmissions with late 70's cranks.  Check with the smarty pants gurus to be sure.  I don't believe it's a big deal.  For a 76 401, which is a nice find by the way, there are good transmission options out there.  For automatics, I personally like the TH-400 trans.  It was never offered in an AMC car, but it was the only option available for any of the v-8's in jeeps since the early 70's.  They are bullit proof, and are easily converted to 2wd by a trans shop.  They are cheaper to rebuild than the other good option (727).  The 727(a mopar tranny AMC used as their heavy duty trans and was available in the 68's I believe) will be easier to bolt in though.  Don't use the 904 trans if you can avoid it, just too weak for even a stock 401. 

     As far as manuals go, the strongest stock trans is the mid 70's super t-10.  It's generally thought to be comparable to the famed M-22 rock crusher.  It will handle your 401 with some strong modofications.  If you can get one out of a mid 70's javelin, amx, make sure that you pick up the bellhousing as well.  It'll bolt right up.  The earlier design t-10 was available with in your 68 so a 401 and a super t-10 should bolt up using all 68 stock available parts.  Should be a completely dead bolt in.  And good fun I might add!  Late 60's t-10's are also good units as long as you don't throw TOO much power at them.  If you have any intention of building up a 401, and 450 ft.lbs. of torque is very easily accomplished, you should consider tranny strength now.

     Swapping in a world class t-5 form a mustang is a popular swap. It requires using an 80's AMC or Jeep bellhousing, but even the early 90's improved version is only rated at a shade above 300 ft.lb.  Not very strong!  If you want to go with a 5spd overdrive capable of handling a strong 401, the aftermarket Tremec TKO 500 is rated for 500 ft.lb. of torque and can occasionally be found at a decent price.  They are bigger in size though and may cause problems, fittting in the trans tunnel, linkage modification, shifter location,  etc.  Check with the really smart guys on that one.  

If you have more questions e-mail me at gschuld@hotmail.com

thank you for your reply it has much informed me .  

With the dodge van tranny out of the 318, check what side the starter hole is on.  some dodges had them on the wrong side for amc swaps.  I have a 904 from 1980 bolted to a jeep 360 from 1985 with no problems.