71 Dodge Dart swinger 318 to 360 swap

Heres what I have:  1971 Dodge Dart Swinger with a 318 engine and a 904 transmission, with the 8 3/4 rearend. 

I already have a 360 motor that I am planning to put into the car in the near future. Aside from a different engine mount and torque converter, is there anything else that I need to do this swap?  I am planning to use the 904 trans that I already have.

Thank You--Ryan

the 360 is not balanced to the 904 trans., it will vibrate  

Yeah, that's about it ryan.  Keep in mind though, if the 360 you have already has spool type motor mounts or the older pad style like your 71 already has.  You might be chasing more than just the one mount, as you already know the 360 has a different mounting pattern on one side.

Also, you might want to consider using headers if you don't already have them, 318 manifolds aren't much in the way of making power.  Installing headers on an A body is a challenge.

Make sure you KNOW for sure that the converter you get is offset balanced for a 360.  If  you are dealing with a local trans. shop you would be surprised how little some of these guys know about mopar stuff.  I learned the hard way on the converter.  After telling the shop to give me one for a 360 when I did my swap they gave me a 318 one anyway and the car shook like hell.  If you this happens to you, it will be very obvious what has happened!!!!!!!!!!  I ended buying a balance kit from mopar which was still available at the time and had them welded on to my stock 318 converter to make it right.  The kit comes with a template to show weight placement.

Your 904 trans should work just fine, I have the heavy duty 360 style one (A999) which has a couple extra clutch plates and a wider low reverse band.  A 318 trans should be plenty tough for a mild 360 though.

Instead of finding a converter to match your new power train you can use a B&M flex plate that will bolt directly to your 360.
These flex plates are balanced according to the engine and are a simple fix for external balance motors.
They work great and are SFI approved for your dodge.  

What you can also do is have your crank balanced with the flex plate and use a converter without wieghts.I have done the same swap with my Dart and had no vibration.  

yep, no problem with your combo as long as you have the 360 weight put on your convertor. if its in your budget i would find someone to freshen up the tranny and upgrade it with the 360 type internals.340 exhaust manifolds would look good if you can find a pair for decent money. its the left side mount thats different, iam lead to believe 360 truck will work.(guys, please correct me if iam wrong on the mount as i need to know also. iam putting a 410 stroker into what was a 72 challenger that had a 318). your probally be using a 4barrel so you will have to find the correct tv linkage. other than that it should be a bolt in. good luck with your project and remember.....go mopar or go home.  

I am doing a 318 to 360 swap in a 74 challenger what modifications have to be done to the left motor mount and what would be the matching transmition for a 360 motor? I was told I would have to cut the drive shaft to put in a 360 trans is this true.  

74somedayproject:
I am doing a 318 to 360 swap in a 74 challenger what modifications have to be done to the left motor mount and what would be the matching transmition for a 360 motor? I was told I would have to cut the drive shaft to put in a 360 trans is this true.

iam not a 100% on the mount anymore. i wish someone who has done it, speak up so we all can put this question to rest once and for all. the 727 is longer and larger, so if your stepping up from a 904 you will have to modify your driveshaft.  

A.. I went to napa and asked for 74 Dart 360 motor mounts and they went right in and it wasn't too bad of a price.


Q...I built a nasty 360 and swapped out my 273 in my 67 GT and found that the 904 wasn't tough enough I want to swap in a 727. Will the crossmember be different or will it bolt right in? I know what to do with the driveline however, Will the tranny cooler in my 67 be big enough for the 727? Thanks Mopar or no car!!!!!!!!!!  

I'll throw this one into the mix.  I have a 63 fury with a 318 poly and a 727 torqueflite.  What kind of issues will I run into swappping the 318 poly with a 360? Has anyone done this?  

i know that the poly blocks had the big block bellhousing bolt pattern.  i was gona swap out a 318 poly out of a 67 dodge truck and put my 408 small block in but found the bellhousings to be different.  it bolted right to a big block i had on a shelf.  i had to get a small block bellhousing for it to work  

I know the left motor mount is different on a 340 but not sure bout the 360. I put a 360 in an a body once and I had to work on it for 2 days and do alot of engineering just to get the mounts lined up. I would have bought new mounts but it was a buddys car and heaven forbid him spend the extra dollar!