Moparts

Swapping 1990 318 to Newer magnum 360... Help?

Posted By: 1967-418

Swapping 1990 318 to Newer magnum 360... Help? - 03/26/13 06:27 AM

So I have a 1990 d150 318. I was just going to get the 318 goin but it has a bad knock so I was looking at the magnum 360s. I found a few good deals on 360 magnums out of newer rams but was wondering if the work and money is worth it. I really couldn't find any helpful websites about this. Has anybody ever done this kind of swap? I was wondering how the wiring, computer, and electronics would work with the swap? and if it would be better to keep the efi on the magnum or convert back to carb or just keep the throttle body. I'm 18 and new to all this so help me out. I just don't wanna get into something that I can't finish.

Thanks in advance.
Posted By: 85_Ram_4speed

Re: Swapping 1990 318 to Newer magnum 360... Help? - 03/26/13 11:32 AM

I did it to my '85 making the 360 Magnum a carbed engine. I should have followed through and done the stock injection but never did. Now I have something much bigger in the bay that uses more gas but is fun to

This was from a post on the subject I responded to:



Quote:

Provisions are on the block for the old style motor mounts.

If the plans are to use a 904 trans or any variation there of with a mini starter (stock starter on a magnum), then you will need to grind the boss on the block to get the starter to sit flush on the trans case as it should. This is because the 904 moves the starter in a different spot closer to the block. Not sure on a old style stock big monster starter, but does anyone but the resto guys even uset them anymore? I wouldn't even bother with that heavy thing. BTW, you may or may not have to lengthen the battery to starter cable--I had to with headers. here is a pic of where to grind for the starter.




Swapping into a truck requires the truck power steering bracket be used. The van bracket puts it into the framerail--don't ask me how I know. My '85 power steering hoses bolted right up to the magnum pump, the return hose is obviously a clamp on and works fine.

If your sticking with the stock magnum flexplate and old style trans, you need to slot one hole on the flexplate so the torque converter bolts up. This needs to be done whether its a 360 or 318 with the stock flexplate. If someone finds this in a search, for future reference, on a 360, you MUST use the magnum 360 balanced flexplate--it is balanced differently than a 360 LA engine. A 318 LA or magnum WILL take any standard flexplate LA or Magnum as they are internally balanced.

You can keep the serpentine setup no problem, but the magnum has no fuel pump provision, so you'll need an electric pump to fit your needs.

Going carb is super easy, just get a carb intake and swap in as if it was a LA engine. Obviously depending on intake and trans combo, the throttle and kickdown linkage need to be worked out, and factory parts may not work without fab work. I had to make my own kickdown rod for mine. Stock LA electronic distributor/ignition system drops in and hooks up just as normal.

If going injection, yea, your going to be into some work. You obviously need a larger PSI fuel pump / regulator vs. the carb setup and figure out the wiring or buy a harness--I believe there was someone on Ebay selling a simplified factory harness. You definatly need to keep the stock magnum flexplate so the crank sensor will work too. Having a donor vehicle is nice, but not necessary, you need to add a feed and return fuel line which can be done with a stock carbed fuel tank, but yea, if you can make the Van tank work, go for it--but I think the filler hole will be more towards the rear of that tank. It may be possible to use a truck tank with even less mods on an older truck so you can get the right fuel pump--both old and new trucks use the side mounted tanks. Hard to say until you put them side by side. Making a set of tank straps would not be hard at all if you can weld and do minor fab work.

Radiator hoses are a snap if your using a stock radiator, just get a set for a '93 truck as they had the magnum engine stock with the older body style.

Just about any header or stock exhaust manifold will work in a truck swap--I have seen car headers stuffed in there too, but the truck headers fit much much better IMO. I had full lengths and shorty style meant for a 94-6 ram in there--of course I had to fab my own exhaust.

I think thats about all I got to do a magnum swap.



Posted By: BBD150

Re: Swapping 1990 318 to Newer magnum 360... Help? - 03/26/13 02:36 PM

any idea how the swap ability between pre mag blocks and mag block parts are? im looking into doing a 360 swap on a 1994 dakota for a friend. it has a 318. i have a 1984 cast 360 block that he wants to put in it. will mag heads bolt to a non mag block? will a mag intake bolt to non mag heads? i was planning on keeping it fuel injected. but im not sure of what other hidden surprises i will be looking at.
Posted By: BEINGmeISaCRIME

Re: Swapping 1990 318 to Newer magnum 360... Help? - 03/27/13 02:16 AM

I did a 318 magnum swap into my 70 coronet. Motor mounts and everything is the same as the old style. I think you'll have to get 360 mounts for your truck and put on the 360 magnum. Something else you got to think of is getting the right flex plate/flywheel for the 360 magnum that will allow it to mount to a 904/727.

My 318 magnum with 904 DID NOT require any grinding to the block to get a mini starter to fit. The engine braces that go between it and the transmission would not work with headers, manifolds should be able to.

I would think making it carbureted would be easiest for you. Theres a couple different intakes you could use that have the magnum bolt pattern. You'll have to upgrade the wiring on the magnum alternator (100+ amps on charging circuit) But that isn't a big deal.

Oh yeah: definitely worth it.
Posted By: BEINGmeISaCRIME

Re: Swapping 1990 318 to Newer magnum 360... Help? - 03/27/13 02:20 AM

Quote:

any idea how the swap ability between pre mag blocks and mag block parts are? im looking into doing a 360 swap on a 1994 dakota for a friend. it has a 318. i have a 1984 cast 360 block that he wants to put in it. will mag heads bolt to a non mag block? will a mag intake bolt to non mag heads? i was planning on keeping it fuel injected. but im not sure of what other hidden surprises i will be looking at.




Mag heads can go on an LA block. LA engines oil to the cam and pushrods differently than a magnum engine so you will have to have oil through pushrods and lifters (IIRC you need an AMC lifter for flat tappet). The Magnum does not use shaft mounted rocker arms like an LA motor. Magnum intake will only fit on magnum heads unless you are a machinist and can modify the bolt holes. The magnum intake bolts go straight up and down and the LA go in diagonally. Seems like if you're keeping the fuel injection you would want a computer for a 360 since there's more displacement, therefore more air and fuel moving through the engine.
Posted By: BulletBob

Re: Swapping 1990 318 to Newer magnum 360... Help? - 03/27/13 06:01 AM

Quote:

any idea how the swap ability between pre mag blocks and mag block parts are? im looking into doing a 360 swap on a 1994 dakota for a friend. it has a 318. i have a 1984 cast 360 block that he wants to put in it. will mag heads bolt to a non mag block? will a mag intake bolt to non mag heads? i was planning on keeping it fuel injected. but im not sure of what other hidden surprises i will be looking at.



Unless you have some fabrication tools the 84 block won't be easy to do
The Dak uses those three bolt holes that the 84 block doesn't have

Attached picture 7642578-SAM_3656.JPG
Posted By: BulletBob

Re: Swapping 1990 318 to Newer magnum 360... Help? - 03/27/13 06:05 AM

Here's how one looks carbed with Mag serpentine drive

Attached picture 7642584-SAM_3662.JPG
Posted By: BBD150

Re: Swapping 1990 318 to Newer magnum 360... Help? - 03/27/13 06:30 AM

Quote:


Unless you have some fabrication tools the 84 block won't be easy to do
The Dak uses those three bolt holes that the 84 block doesn't have




so the motor mounts between the blocks are different. havent had a chance to look at the dakota yet.
Posted By: BulletBob

Re: Swapping 1990 318 to Newer magnum 360... Help? - 03/27/13 06:38 AM

The early Dak block is the first to have those mount holes
Posted By: 1967-418

Re: Swapping 1990 318 to Newer magnum 360... Help? - 03/28/13 12:49 AM

Ok. Thanks. But I got another conern before I start the project. Right now the truck has a throttle body on it. And I was wanting to convert it to carb but I was wondering what to do about all the wiring and the accessories hooked to the throttle body. Also the sensors. Any easy instructions or diagrams?

Thanks
Posted By: 85_Ram_4speed

Re: Swapping 1990 318 to Newer magnum 360... Help? - 03/28/13 01:51 AM

If your converting it to a carb, you need a different intake to put the carb on. At that point, non of the magnum wiring even matters. You pull the stock magnum injection intake and all the wiring off and put a carb and carbed intake on.
Posted By: 1967-418

Re: Swapping 1990 318 to Newer magnum 360... Help? - 03/28/13 07:43 PM

But right now the truck has a throttle body on it with a bunch of wires and sensors that are hooked right to the throttle body. My question is if I convert it to carb where's all that wiring and acessories on the throttle body gonna go once there's a carb with not place for all this stuff to hook up?
Posted By: 85_Ram_4speed

Re: Swapping 1990 318 to Newer magnum 360... Help? - 03/29/13 12:59 AM

Oh, I got you now.

Well, the thing is, some of that stuff may or may not be useful if you put the magnum fuel injection on. Me personally, I have no issues with rewiring a vehicle, but I always use good wire and solder and shrinkwrap everything. I personally would chop off anything not needed in the swap, you may choose to just tie it all back to the main harness or just out of the way.

And another note if your going to cut out the excess. Either get a diagram or figure out where it all goes. You can very easily cut something that has a splice hidden somewhere that feeds something you need. Just be cautious.
Posted By: BBD150

Re: Swapping 1990 318 to Newer magnum 360... Help? - 03/29/13 01:29 AM

Quote:

But right now the truck has a throttle body on it with a bunch of wires and sensors that are hooked right to the throttle body. My question is if I convert it to carb where's all that wiring and acessories on the throttle body gonna go once there's a carb with not place for all this stuff to hook up?




im not 100% sure how the throttle body wiring harness is without looking at mine. when i did my big block swap in my 87 there was a small harness for the carb. it goes back to the firewall to the main harness and there is a connector. i just unhooked it there and took all of it out as i didnt need any of it. i think the oil pressure wire for the gauge is in it but i used an aftermarket gauge.
© 2024 Moparts Forums