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401 swap

Discussion in 'Intermediate CJ-5/6/7/8' started by solomon, Jul 26, 2006.

  1. solomon

    solomon Baby Jeep Junkie

    would a 401 be easy to swap in place of a 304?
     
  2. High5

    High5 Member

    Yep till you start breakin stuff.

    That family of engines have the same exterior dimensions and motor mounts and such.

    You will need a flywheel for the 401 if you are running a manual. They are different than the 304
     
  3. solomon

    solomon Baby Jeep Junkie

    Going to pick it up this afternoon. I'm gettin the t/tc too. I figured it'd be a good idea with the bigger motor, and he said I could take it all, soooooooo........

    we'll see how it turns out.
     
  4. BlueFlu

    BlueFlu past owner of some ecj5's

    Weee doggie. That lil 5 will scoot!!
     
  5. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    The 401 is a great engine, but a lot to handle in a CJ. A lot of engine for the drivetrain too - likely too much, depending on your driving style.

    The swap is as easy as they come though. What kind of vehicle was it in?
     
  6. Txjake

    Txjake I wrenched with Sparky

    Brian Chuchua Jeep used to swap in 401s into CJ5s and sell them new at his dealership....:shock: :)
     
  7. solomon

    solomon Baby Jeep Junkie

    It came out of a 74 cj5, or at least that's what it was in when I bought it. Don't worry Tim, I'm softfooted. I find myself driving 50 up the highway sometimes. I went and picked it up this afternoon. It's got a good Dana 44 rear, and he said the transfer case and transmission were excellent, but I'm not sure what model they are. I really bought it for the engine. And on top of that, the body is in a lot better shape than mine. I think just from looking that I've got a lot of good stuff to work with. The only thing I'm not sure about is the power steering pump, which there was none on the motor. I'm gonna have to rig that up somehow.
     
  8. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Mmm... sounds like you should keep the '74 intact and drive it. You'll do a lot of work to move all this stuff over to the '77, for little (if any) gain.

    All the 304 external stuff should fit on the 401, ie PS pump and brackets.

    I worked at Chuchua's ca '74, and they sold a few custom Jeeps, like the 401 CJs. They did a lot of custom stuff early on, but less as time went by. They built a TH400 equipped CJ-6 for a disabled Viet Nam vet (with hand controls) while I was there, a race-prepped CJ-5 for for the Four Wheeler editors to run the Baja 500, and a 401 equipped M715, plus the race cars and likely other stuff that I don't remember offhand. I drove their '73 401 CJ-5 demonstrator before I bought my '73 CJ-5.
     
  9. JeepTherapy

    JeepTherapy Sponsor

    I did a CJ5 and CJ7 with a 401. MONSTERS! First time I drove the 5 I got a little heavy footed leaving a stop light. Ate first gear :( The CJ7 had a turbo 400 into a Dana 20. That one had the transmission replaced three times. Both were a blast to drive. The 5 was my roomates the 7 was mine. Both needed fixed often. I think you should pass on the 401 and trade it to me for a tired 304 ;D
     
  10. solomon

    solomon Baby Jeep Junkie

    I can see I'll have my hands full with the 401. If I were to maybe go searching for axles/transmission/xfer case that really would stand up to it, would should I be looking for?
     
  11. Txjake

    Txjake I wrenched with Sparky


    :drool: :drool: I envy you for working at such a place from Jeep history. A 715 with a 401 would be a primo rig, I bet. Closest I have ever come to a 401 CJ5 is my old Scout 800 with a 440 Mopar in it......:(
     
  12. gschretter

    gschretter Banned

    Something to think about.

    Maybe switch to a chevy 350.

    There are more parts, options than a 401.

    Also parts seemed to be cheaper with a 350.

    If you are broken down in some off the wall place, I bet they will have stuff for a 350 and for a 401 they might have to order.

    I broke down in Alpine, TX (very small, in the middle of no where place), when I told the auto parts store that I had a cj5 they told me they do not stock parts for that vehicle, but when I told them I had a chevy 350 in it they said they had every part I need, even a whole engine in the back.
     
  13. solomon

    solomon Baby Jeep Junkie

    I can see how chevy parts are always readily available, but I'm trying to use what I got. Plus I don't know enough about em to wanna fool with adapters and such. From what I can tell they're not cheap either. I'm gonna go broke doing this, but I'd like to have enough to buy a beer when it's over with.

    I won't be driving far in it. The main trip I'll make is 20 miles to the hunting camp. You won't catch me on the highway in another state in it.
     
  14. High5

    High5 Member

    The chevy swap probably isn't any cheaper when you figure in the adapters, radiator swap, and exhaust changes. True, you might have to wait for parts, but it's not like your a "geographical oddity" and two weeks from everywhere.R)


    High5
     
  15. solomon

    solomon Baby Jeep Junkie

    From what everyone's been telling me the 401 should be a direct bolt in, right?
     
  16. Txjake

    Txjake I wrenched with Sparky

    I vote for the 401. From what I have been told, it is the same physical size as the 304. Timgr would have the particulars. There is little substitute for cubic inches, if you are going to turn some big tires, but all that torque will most likely snap something. still should be fun! :) :twisted:
     
  17. solomon

    solomon Baby Jeep Junkie

    I had posted the question about ideal axles/transmission/transfer case for the 401. I'm not heavy footed by any means, but I don't want to tear anything up either. I wouldn't be opposed to doing a little searching and paying for an ideal setup.
     
  18. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Yes, it's the same block design as the 304 and 360. All the external dimensions are exactly the same. Internal parts will not exchange though. Your 401 will have "401" cast in to the block in about 1 1/2" high letters on the drivers side in front of the motor mount. The only changes needed should be minor, like fuel line location, accelerator linkage, maybe some wiring.
     
  19. mb82

    mb82 I feel great!

    Remember guys years ago a 350 was a 350 was a 350. But now they are not exactly like that. Yeh a good number of the parts still match up but not all. And with my luck I would break that part that isn't
     
  20. mbalbritton

    mbalbritton Member

    Keep it a Jeep.... ya I know Jeeps are made of all makes, but it's a pet peeve of mine to come across a Ford T-bucket, or 32 coupe, or CJ with a SBC in it. erks the crap out of me. Ya they're good motors, ya parts are plentiful and cheap, I understand all that. But the charm of having the elusive 401 under the hood is irreplaceable!

    Heck, put that 401 in there, and I'll make you a free 401 sticker for you to put on the hood!