LA 318 to Magnum 360 swap

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73dartneedswork

73dartneedswork

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I made the decision to go with a Magnum 360 to replace the LA 318 in my 73 Dart. It was half price day at Pick N Pull so I was able to get the motor for $122. out the door.

When you buy a motor from Pick N pull you're not able to start if to hear how it sounds. You cant even have a battery out there to try and do a compression check. The millage of the 2001 Ram I pulled it from was unknown because the instrument cluster was gone. I did pull the intake manifold and valve cover and I didn't see much to any sludge. I also pulled the oil pan and everything looked good. The was no metal in the bottom of the pan or in the oil pick up tube screen. I could still see cross-hatching on the cylinder walls.

Due to budget restrictions I don't want to change the cam or heads. I really don't want to pull the heads unless I have to.
I think I'll do a leak down test and see where that takes me.
What else should I do to ensure I have a good motor before I drop it in the Dart?

From what I've read I know that I'll have to make the following changes.
360 car pan
360 car engine mount or possibly modify the ones from the 318
check header clearance against the block
I plan on using my LA pulley's, water pump and timing cover. I'm going to switch to an electric fuel pump. I'm not sure if I need a new harmonic balancer or not.
Intake manifold that fits the Magnum heads.
Magnum 360 flex plate and the converter off the 318.
What else am I missing?
Magnum360_zpsecb33d38.jpg
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hopefully the heads aren't cracked, but I have yet to see a set that aren't, they may not be leaking but good chance they are cracked
 
Usually if the heads are cracked, they are cracked in a place that does not effect anything. I would drop it in and run it.
 
okay budget build go back to pick n pull and get a car pre magnum 360 oil pan and pickup. It must be a 360 or it wont fit (read 318 does not fit). while there get a balancer off a older 360 magnum that the front pulley bolts on or see if yours is a bolt on pulley. front of oil pan will have two pressed notches in it. use a hammer and dolly and just flatten them out don't make this any harder than it is. This lets you use a one piece magnum gasket. crosswind intake and your good to go. All stock 318/360 early stuff will bolt to front of motor as will standard electronic/points distributor. I ran a flywheel so no clue on running correct flexplate for 727/904. I would stick a new timing chain in it and as long as i found no metal in the pan or loose rods drop it in and run it

grind truck mounts off side of the block they will not clear hedders
push rods bend very easily so might consider good set. (if you beat on it they will bend)
post a wanted ad on here for set of 340 engine mounts (what I did and it saves lots of grief)
If you can go back to truck you got motor from and pull the tranny pan off. If it is full of metal you have a good motor. I am with 318willrun drop it in and run it. Don't get perfect-itis
 
I did a similar build (stock bottom end magnum) you should check clearances on rod and main bearings before dropping in. My motor looked beautiful and the cylinders still had cross hatching but I still had to do Rod and Main bearings before dropping in.

Go back to the junk yard and find a pre 1996 magnum 360 balancer, they had the six bolts holding the serpentine pulley on. That's what I did. Works great with no vibrations.
 
You also need a center sump oil pickup. Before you tear it apart put a manual oil pressure gauge on it and prime it to check oil pressure.
 
I've made a little progress
LA 318 that I've been running the last couple of years. It's been a good little motor that I bought off of Craigslist for $200. It got me into the high 14's.
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The motor is out
20141213_212036_zpsd94b942d.jpg
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with some shimming can I use the 318 mounts on the 360? The car is a 73 with the spool type K-member.
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mderoy340 said:
just use washers and a longer bolt and your good to go.
Click to expand...

That is what I did many years ago.
If you have access to welder make a spacer and weld it to bracket. Or even tack all washers together. Saves dropping them during install or removal.
 
It's been a while since I've given an update.

I had second thoughts about just dropping the motor in and running it.
I took the heads to a machine shop and they said they're cracked. They also said the valves are tulliped.
I'm going to do Engine Quest Heads and a custom grind cam on a la roller cam core so I can run a mechanical fuel pump.

Who on the net sells complete Engine Quest heads that are actually bolt on ready?

I called Comp Cams about getting a cam and the guy was confused about what I wanted to do, which in turn confused me. So to clarify, I need a long snout cam from a 89-91 LA roller block correct? I just need to make sure they understand the rocker ratio is 1.6 so that I don't get to high of lift.

I did get some holes filled in my engine bay and I repainted it. I just need to put a motor in now.
Dartenginebaypic_zps70dacdd2.jpg
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73dartneedswork said:
It's been a while since I've given an update.

I had second thoughts about just dropping the motor in and running it.
I took the heads to a machine shop and they said they're cracked. They also said the valves are tulliped.
I'm going to do Engine Quest Heads and a custom grind cam on a la roller cam core so I can run a mechanical fuel pump.

Who on the net sells complete Engine Quest heads that are actually bolt on ready?

I called Comp Cams about getting a cam and the guy was confused about what I wanted to do, which in turn confused me. So to clarify, I need a long snout cam from a 89-91 LA roller block correct? I just need to make sure they understand the rocker ratio is 1.6 so that I don't get to high of lift.

I did get some holes filled in my engine bay and I repainted it. I just need to put a motor in now.
Dartenginebaypic_zps70dacdd2.jpg
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Click to expand...

As for bolt on heads: Hughes engines/ Competition Products, sell assembled heads in the 900 dollar zone. Depending on your budget, might send 0U812 a P.M.. The other guys assemble the heads, they work. Ou812 does a really good bowl cut, blueprints everything to a better spec.(budget becomes the deal, here. He's in So Cal)
On the cam: I run a LA retro fit hydraulic roller, (Howards Cams) in my Magnum. At Comp, cam recommendation guys are all over the map. The rocker ratio needs to be reminded, as well that the camshaft is ground , on a cast iron can core. I have seen billet cam cores , witch requires a bronze distributor gear. (Another P.I.T.A...)
Another thing, to think about: Try to keep lift, under .520" -wish lift. After that, the valve guide heights will need to be turned down.( I would have it done , anyway. Make sure you have at least (100 lbs on the seat-, 300-320 full open lift, on valve spring pressure) ,good valve springs.
P.S.:Nice engine compartment...
 
A body is correct, la roller cam so you can run mechanical fuel pump that's what I did. I wonder why comp is confused by that? Try talking to a different tech maybe?
 
You're right about Comp cams tech staff. They are all like weathermen. All over the place and mostly wrong,They gotta be. I called in 6 times for a cam recommendation on the same engine and application and got 6 different recs from the "professionals". Better guess with a ouija board. $7.00 an hour tech grads.....
 
I have a question about the intermediate shaft.
The shaft in the Magnum engine is steel correct?
If I go with a cast iron LA roller cam then I need to get a cast iron intermediate shaft?
 
73dartneedswork said:
I have a question about the intermediate shaft.
The shaft in the Magnum engine is steel correct?
If I go with a cast iron LA roller cam then I need to get a cast iron intermediate shaft?
Click to expand...

Ask for a cast iron cam core,that will work with a LA intermediate shaft. I recommend Mopar P3690715 (heavy duty piece,IMO).
 
I've got all my parts on order to finish the swap.

My initial plan was to go as cheap as possible but that has changed. I want to be confident that the motor I'm going to install is going to run well.

I bought the small valve Enginequest heads with the LA bolt pattern. For now I'm going to run my Performer intake and 600 carb

I ordered a Howards long snout roller cam. I wanted good idle and vacuum. I also don't think I will upgrade my torque converter. They recommended 209/217 @50 with 496 lift on 1.6 rockers, 112 LSA.

I have new lifters, balancer, oil pump, oil pump pick up tube and double roller timing chain on order as well.

I found a machine shop who is going to go through the bottom end and install the cam and heads that I'm providing.

Hopefully I should have everything back together in the next couple of weeks. I'll post pictures as I go. Thanks for everyone's help!
 
73dartneedswork said:
I've got all my parts on order to finish the swap.

My initial plan was to go as cheap as possible but that has changed. I want to be confident that the motor I'm going to install is going to run well.

I bought the small valve Enginequest heads with the LA bolt pattern. For now I'm going to run my Performer intake and 600 carb

I ordered a Howards long snout roller cam. I wanted good idle and vacuum. I also don't think I will upgrade my torque converter. They recommended 209/217 @50 with 496 lift on 1.6 rockers, 112 LSA.

I have new lifters, balancer, oil pump, oil pump pick up tube and double roller timing chain on order as well.

I found a machine shop who is going to go through the bottom end and install the cam and heads that I'm providing.

Hopefully I should have everything back together in the next couple of weeks. I'll post pictures as I go. Thanks for everyone's help!
Click to expand...
You will be happy,with the extra money spent. That's a nice daily driver type combo.
 
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