Swapping a 360 from A-Body/auto into a '78 Dodge Van with factory 318/4 speed - Advice?

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As the title says....
My van has a factory 318/4speed setup in and the 318 is very tired.
I picked up a 360 from a member here that came from an A-body with auto trans.
I figure i will need to swap oil pans and pickups probably. I am totally unclear what wiil/won't mate up on the back side though.
I believe 318's are internally balanced as opposed to the 360 that's going in. Also wondering about pilot bushing and/or depth of the hole in the back end of the crank, from reading other threads here before posting this one.
Any advice to make this swap as painless as possible would be greatly appreciated!

Thanks,
Doug
 
Oil pans do not interchange between 273/318/340 and the 360. 360 has smaller "half moon" at the rear main

The 318 is neutral balance, so you'll need a 360 flywheel, and pay attention whether it's 13? teeth or 142.

So far as the crank depth you need to measure it. I've always just measured from the tip of the pilot to the transmission face, then compare THAT to the transmission face of the bell to the bottom of the crank hole, which should be deeper of course

If the hole is not "finish machined" in the 360 use the larger magnum/ Jeep pilot bearing which fits in the large converter bore. They can be had either as needle roller or bushing. I would not necessarily use needle roller on that old pilot

You want the balancer that came on the 360, it is weighted.

Late style pilot bearing/ bushing fits converter bore

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Thanks guys, not sounding as simple as I was hoping! I don't have the flywheel from the 360, just the flex plate. Motor mounts are different too??? I suppose they are also different for a van as well...?
I was hoping to do this all in one weekend but it sounds like i might have to pull it out first and do some parts verifying/ordering afterwards.
 
The motor mounts aren't different, just the left or drivers side bracket. The cast iron "ears" on the blocks are different between 273-318 (use same LF bracket) and 340-360 (Use the same LF bracket)
 
You should be able to modify the 318 engine brackets to fit the 360

You will likely have to buy a 360 flywheel

In the mid 70's I had a 360 in an old Landcruiser, later a 340. I had a balanced flywheel (340) and knew better, but ran it anyway. IT DID SHAKE at some RPM points.
 
This is a really easy swap so don't get your underwear in a knot,lol.
Although; the van won't need the 4-speed anymore, and I would consider putting the 727 into it. That swap would be a little more detailed,tho.
 
AJ/FormS said:
This is a really easy swap so don't get your underwear in a knot,lol.
Although; the van won't need the 4-speed anymore, and I would consider putting the 727 into it. That swap would be a little more detailed,tho.
Click to expand...
No way I would want to ditch the factory 4 speed, that's what makes the van so much fun to drive, and rare too!
 
skep419 said:
1969 Dodge Dart GT freshen up
Click to expand...

Thanks so much! That simplified things for me big time... It turns out the crank I have in my 360 is already set up for a 4 speed with the proper drill depth of 1.964" and will accept the pilot bearing (Timken# FC69907) with the outer dimension of 1.816 and inner diameter of 0.751.
So, I think all I should need now is the correct flywheel (balanced with 143 teeth) and I should be ready for the swap.
 
Well, I THINK I have everything about ready to do the swap this weekend (new flywheel for 360, Oil Pan with rear sump, pilot bearing for the 4 speed, correct motor mounts. I put a new water pump and fuel pump on it just to be safe.

One last thing I am wondering about is if the 318 exhaust manifolds will match up without any issues?
The 318 currently in the van is the factory 1978 engine and the 360 going into it is from 1972.

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Be sure to mock up the bell and measure from the transmission face to be sure the pilot hole is deep enough for the shaft. It's reported that some "smog" heads have fittings that might interere with some manifolds and need plugged I've never dealt with that
 
The manifolds will bolt up no problem but the 318 manifolds might have a smaller inside diameter. Take a gasket and compare it to the manifold and cylinder head to see if it matches up nicely to both.
 
BlueDream said:
The manifolds will bolt up no problem but the 318 manifolds might have a smaller inside diameter. Take a gasket and compare it to the manifold and cylinder head to see if it matches up nicely to both.
Click to expand...

What I have found from researching part numbers on Rock Auto is that for the vans, at least, they use the same exhaust manifolds for the 318 AND the 360, right on through the 80s... This would leave me to believe they are the larger ports for the 360 size and I SHOULD be just fine.

Maybe I could gain a little performance if I switched to the mid 90's magnum manifolds but they exit at the rear rather than down straight at the middle, so I would definitely have to modify the exhaust hookups if I went that route.
For now, I am going to just see what it all looks like when I pull the 318 and compare.
Fingers crossed, thanks everyone, for all the input, I will update when I get further along!
 
Well, it's time to stuff it back in...
I Made a template needed to drill out my existing small flywheel based on the drawing I found from more research here ( thanks for your old post @crackedback ).
Turns out the old 318 exhaust manifolds have the larger ports needed for the 360 so I lucked out there.
-fingers crossed! Doing it all alone so moving nice & slow. There's no room to spare, it's a very tight fit.

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