318 or 360?

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George Lawicki

George Lawicki

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Hey guys,

Swapping out my /6 for a V8 and I can get a nice complete 318 for a decent price. My thoughts are should I hold out for a 360 or get the 318? Its not going to be a race car but I would like something that has some get up and go to it.
 
Either will have get up and go compared to the /6. 360 LA's are getting a little more difficult to find, at least in my area. However, 5.9 magnums (360) are easy to find and cheap. There are some things to be aware of, though, when swapping in a magnum. If you can land a great running 318 for a cheap price, nothing wrong with that either.
 
Motor mounts for a 360 are scarce right now, however another member posted a few days ago that there may be some available in 2 - 4 weeks...


318's are good to build, drive, and cruise... Motor mounts for those are easier to find also...


Parts for both engines are common and easy to find...

The 360 will be stronger in overall power... It's your call...
 
I'd say go magnum the Base Hp/Tq is 5.9L with 4bbl and headers, add a mild cam if you want 1 hp per cid.
The powerband is perfect for a street car. Even with a 5.2l magnum you'd be further ahead.


screenshot_20171212-101519-png-png-png-png.png
 
Agree with both of the above posts. First order of business is to make sure you have the correct mounts for your year chassis and intended engine, in hand. Unless you're willing/capable of doing some fabrication. Too many people get all starry-eyed and build their dream motor and then realize they have no way to mount it in their car- and then it just sits on an engine stand in the corner of their garage. So before even starting, get the mounts for a 318 or 340/360/Magnum to a slant 6 K frame of your year before you even start, unless your plan is to swap to a V8 K frame. Either way, HAVE the parts. The project can go no further if the parts aren't available. The same goes for the exhaust- have the proper manifolds or headers ready to go before you even start. Those are the two biggest holdups on projects like this. Good luck with your project!
Edit- And you do realize the transmission needs to be swapped to a small block V8 unit too, right?
 
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The 318 is internally balanced, responds well to basic upgrades, 4 barrel, good exhaust, cam, and ignition. 360 has better heads. I'd prefer the 318, others prefer the 360. Done right either should make a nice driver.
 
So for the 360 I would of course need motor mounts (which are hard to find )..... BTW it is a 74 Dart its going in.
What is the big difference between the early LA 360 and a Magnum? or even a crate 360?

the 318 I can get comes with the trans and rear and driveshaft..
The 318 mounts are available...not sure what headers I would need and Im pretty sure a muffler shop would have to build me an exhaust system????/

All this info is helpful indeed So all input is appreciated.

And for ***** and giggles, if I were to take it to the track I would hope to run high 13's possible with the 318?
 
George Lawicki said:
So for the 360 I would of course need motor mounts (which are hard to find )..... BTW it is a 74 Dart its going in.
What is the big difference between the early LA 360 and a Magnum? or even a crate 360?

the 318 I can get comes with the trans and rear and driveshaft..
The 318 mounts are available...not sure what headers I would need and Im pretty sure a muffler shop would have to build me an exhaust system????/

All this info is helpful indeed So all input is appreciated.

if I were to take it to the track I would hope to run high 13's possible with the 318?
Click to expand...
In Order....
  • I've used 318 mounts on 360's, just need to make spacers (I've used nuts)
  • LA 360 is from '71-92. '93-03 are magnums. All magnums have roller cams, oil through pushrods, closed chamber heads, different intake mounting bolt holes, different timing cover/pulleys/water pumps. There are more differences, those are the majors. Good news is alot parts can interchange between LA/Mag motors.
  • 318's have the ability to perform according to what's put in them and what they are put in. There are 10 second street 318's out there, but not on a 2 dollar budget. I put 498 bucks into a stone stock 318 2bbl and ran 14's with 2.76 gears and stock converter.
 
George Lawicki said:
So for the 360 I would of course need motor mounts (which are hard to find )..... BTW it is a 74 Dart its going in.
What is the big difference between the early LA 360 and a Magnum? or even a crate 360?

the 318 I can get comes with the trans and rear and driveshaft..
The 318 mounts are available...not sure what headers I would need and Im pretty sure a muffler shop would have to build me an exhaust system????/

All this info is helpful indeed So all input is appreciated.

And for ***** and giggles, if I were to take it to the track I would hope to run high 13's possible with the 318?
Click to expand...
Sounds like the 318 deal gets you all the parts to do it right.
LA 360s and 5.9 Magnums share a lot of DNA, but the major differences are in the heads, and the EFI on Magnum, although there are carb manifolds available for the 5.9. And the balance is different, too. Nothing insurmountable.
Headers for either are readily available from several vendors, but supplies have been known to vary. Exhaust manifolds for the 318 can come from any '67-76 smallblock A body, the 360 or mag would require 340/360 A body manifolds- although magnum mannies and some others can be made to work *sometimes*.
13s at the track isn't going to happen with a stock 318, but a few judicious additions and a good tune will get you close, as 318willrun said...
 
318willrun said:
In Order....
  • I've used 318 mounts on 360's, just need to make spacers (I've used nuts)
  • LA 360 is from '71-92. '93-03 are magnums. All magnums have roller cams, oil through pushrods, closed chamber heads, different intake mounting bolt holes, different timing cover/pulleys/water pumps. There are more differences, those are the majors. Good news is alot parts can interchange between LA/Mag motors.
  • 318's have the ability to perform according to what's put in them and what they are put in. There are 10 second street 318's out there, but not on a 2 dollar budget. I put 498 bucks into a stone stock 318 2bbl and ran 14's with 2.76 gears and stock converter.
Click to expand...
for the later model 360 you mention different intake bolt holes and timing cover. So like can I go get an edelbrock manifold for that motor or Iam I stock with the factory manifiold and parts?
 
Here the thing if you didn't care about power in the least then I'd say just go 318 4bbl duals and a good tune.

I know power ain't an over concern of yours but a Magnum 5.9l with stock cam 4bbl and headers makes 320 hp @ 4400 rpm very street friendly and powerful, still would make 300 hp with exhaust manifolds.

Do the same thing to that LA318 stock cam 4bbl and headers and I doubt you'd even make 200 hp, even if it made 220 hp thats 100 hp less for the same cost, sure you could add a cam, even a very aggressive cam wouldn't match the 5.9l Hp. plus you could add a cam to the 5.9l and still have 100 hp more than similar LA318.

Never seen a Magnum 5.2l dyno'd but I'm sure it would match the 5.9l or at least make 300 hp.
 
George Lawicki said:
... if I were to take it to the track I would hope to run high 13's possible with the 318?
Click to expand...

It's possible, but driveability may suffer. Magnum exhaust manifolds are 318 port size, and magnum heads flow better than 318 heads but are prone to cracking. If you get the whole 318 and drivetrain for a reasonable price, That sounds really good to me.
 
George Lawicki said:
for the later model 360 you mention different intake bolt holes and timing cover. So like can I go get an edelbrock manifold for that motor or Iam I stock with the factory manifiold and parts?
Click to expand...
speedmaster makes an intake with both bolt patterns. The eddy RPM has two intakes, one for the LA and one for the Mag.
  • LA timing cover works on a magnum, you'll need a car oil pan and pickup. Same with the 318 if it's out of a truck.
  • Hughes sells a fuel pump eccentric kit for 25 bucks or so if you wanted to run a mechanical fuel pump on the mag
 
How much is reasonable priced ?
Depends what comes with it and cheap enough could buy it take what you need and sale the 318 longblock or keep it for back up.
 
273 said:
... Do the same thing to that LA318 stock cam 4bbl and headers and I doubt you'd even make 200 hp...
Click to expand...

Even a low compression 318 marine motor makes 225 hp with a small cam, 4 barrel intake, and carb. If you get the right combination, the 318 would be pretty sweet.
 
Or run the 318 for now, buy and intake that bolts onto both LA and Magnum and headers etc.. and Do Magnum swap down the road, if you buy right most parts can be swapped to 5.9l/360.
 
66fs said:
Even a low compression 318 marine motor makes 225 hp with a small cam, 4 barrel intake, and carb. If you get the right combination, the 318 would be pretty sweet.
Click to expand...

Nothing wrong with a LA 318, but if you have the option of a low 200 hp 318 or a 300-320 hp 5.2l/5.9l and you looking for cheap decent street friendly power , why pick the LA318?
 
Professor Fate said:
Agree with both of the above posts. First order of business is to make sure you have the correct mounts for your year chassis and intended engine, in hand. Unless you're willing/capable of doing some fabrication. Too many people get all starry-eyed and build their dream motor and then realize they have no way to mount it in their car- and then it just sits on an engine stand in the corner of their garage. So before even starting, get the mounts for a 318 or 340/360/Magnum to a slant 6 K frame of your year before you even start, unless your plan is to swap to a V8 K frame. Either way, HAVE the parts. The project can go no further if the parts aren't available. The same goes for the exhaust- have the proper manifolds or headers ready to go before you even start. Those are the two biggest holdups on projects like this. Good luck with your project!
Edit- And you do realize the transmission needs to be swapped to a small block V8 unit too, right?
Click to expand...
What manifolds do I need and transmission U recommend?
 
George Lawicki said:
So for the 360 I would of course need motor mounts (which are hard to find )..... BTW it is a 74 Dart its going in.
What is the big difference between the early LA 360 and a Magnum? or even a crate 360?

the 318 I can get comes with the trans and rear and driveshaft..
The 318 mounts are available...not sure what headers I would need and Im pretty sure a muffler shop would have to build me an exhaust system????/
And for ***** and giggles, if I were to take it to the track I would hope to run high 13's possible with the 318?
Click to expand...
Check the Magnum swap area of the board for particulars between LA & Magnum. One thing missed is Magnums do not send oil updates through the block to oil the valve drain so the use of MOST LA heads is out.

Getting the entire package is a excellent route. That would be a go for it real for me.

If you use headers.... Use Summits headers and dual exhaust kits. Minor trimming with a chop saw or hand saw may be in order. Otherwise, there very very good.
Click here -> rumblefish's Duster project

Otherwise, you could more than likely use what ever exhaust manifolds come with the engine set up if it is an LA. If they don’t work for some reason, you can shop here for a pair.

Use a 904 transmission. That will probably come with the 328 drive train your looking at but ask them to be sure.

FWIW, a stock 318 will not run 13’s. It will require a good bit of parts and work.
66fs said:
It's possible, but driveability may suffer. Magnum exhaust manifolds are 318 port size, and magnum heads flow better than 318 heads but are prone to cracking. If you get the whole 318 and drivetrain for a reasonable price, That sounds really good to me.
Click to expand...

All Magnum heads are the same. The 5.2 & the 5.9 get the same head and exhaust manifold port size.
 
im moving over to the magnum swap form seems more fitting I have more questions so Ill be there thanks guys Iam learning a lot
 
George Lawicki said:
Im gonna go 360.. Iam starting my search tomorrow So I will be back with a hell of a lot more questions.

What manifolds do I need and transmission U recommend?
Click to expand...
Well it sounds like you've decided to go for a 360. If you find a package deal on a 360 with trans, go for it- it'll have all the bits & pieces already to make them work together.
If sourcing things separately, get a mid '70s or later a904 (or one of it's variants: a998, a999) as it will have the part-throttle kickdown on it. It will bolt in in place of your slant six 904; and use the same driveshaft, shift linkage, cooler lines, and speedo hookup as your current transmission. If it was originally backing a 360, you can use the torque convertor and flexplate that comes with it. If it came from a 318 application, you can use the 318 torque convertor with a B&M flexplate #10239 (to balance it to the 360 spec.) This all only applies to LA360s, not Magnum5/9/360s- they're a different animal.
This will allow you to continue to use your (probably, but confirm this for yourself) 7.25 rear end, at least for a little while...
Don't use a trans from a magnum (overdrive) unless you're into frame surgery and structural fabrication.
Exhaust manifolds are easy- any '67-76 A body 340/360 manifold will bolt in, Magnum manifolds will fit with a little tweaking/grinding... Member @318willrun has reported good results using 360 B/E body manifolds, too.
 
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Professor Fate said:
Well it sounds like you've decided to go for a 360. If you find a package deal on a 360 with trans, go for it- it'll have all the bits & pieces already to make them work together.
If sourcing things separately, get a mid '70s or later a904 (or one of it's variants: a998, a999) as it will have the part-throttle kickdown on it. It will bolt in in place of your slant six 904; and use the same driveshaft, shift linkage, cooler lines, and speedo hookup as your current transmission. If it was originally backing a 360, you can use the torque convertor and flexplate that comes with it. If it came from a 318 application, you can use the 318 torque convertor with a B&M flexplate #10239 (to balance it to the 360 spec.) This all only applies to LA360s, not Magnum5/9/360s- they're a different animal.
This will allow you to continue to use your (probably, but confirm this for yourself) 7.25 rear end, at least for a little while...
Don't use a trans from a magnum (overdrive) unless you're into frame surgery and structural fabrication.
Exhaust manifolds are easy- any '67-76 A body 340/360 manifold will bolt in, Magnum manifolds will fit with a little tweaking/grinding... Member @318willrun has reported good results using 360 B/E body manifolds, too.
Click to expand...
Im a bit confused between the Magnum and LA motors LA motors were 2001 and earlier? and Magnum motors 1992 and up???
 
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