Magnum 360 ?

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340inabbody

340inabbody

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Hey guys. I might have an option to get a Magnum 360 to play with for my 1970 Sport Satellite. Its drive train is set up for a LA Small Block.

Other than an intake manifold and carb, cam what else would I need to make it work?

I currently have a 340 in there with headers. I assume the headers are not compatible LA to Magnum?

Thanks for your replies!
 
340inabbody said:
Hey guys. I might have an option to get a Magnum 360 to play with for my 1970 Sport Satellite. Its drive train is set up for a LA Small Block.

Other than an intake manifold and carb, cam what else would I need to make it work?

I currently have a 340 in there with headers. I assume the headers are not compatible LA to Magnum?

Thanks for your replies
Click to expand...
  • headers will work
  • The LA timing cover, and all brackets will work on the magnum.
  • You may need to buy a harmonic balancer, depending on which year of magnum you have IF you are running the V-belt. Running the serpentine belt set up is an option.
  • you'll need a 360 car oil pan and pickup tube
  • you'll need to decide how you are going to deliver the fuel. Electric fuel pump, or swap to a roller cam that has the long snout for the fuel pump eccentric, or use the Hughes adaptor on the magnum cam.
  • You'll need to make sure you have a neutral balanced converter AND the 5.9 flexplate.
 
Mock up the headers to the Magnum before you drop it in- some (not all) headers will hit the mid-block Magnum truck engine mount bosses. A little time with a grinder is all it takes to make it fit, but it's a LOT easier to do out of the car than when it's installed!
 
340inabbody said:
Hey guys. I might have an option to get a Magnum 360 to play with for my 1970 Sport Satellite. Its drive train is set up for a LA Small Block.

Other than an intake manifold and carb, cam what else would I need to make it work?

I currently have a 340 in there with headers. I assume the headers are not compatible LA to Magnum?

Thanks for your replies!
Click to expand...

This is what I did to my 5.9;

(Open) Air cleaner (Mine is a trap door from ‘72.)
750 cfm carb (Edelbrock)
RPM intake
Hooker Super Comp headers @ 1-3/4 (‘79 B body Magnum)
2-1/2 exhaust
MP distributor and Chrome box ignition

Get the flexplate with the engine or you’ll need a B&M (or other, like PRW) flex plate.

If you keep the Magnum front acc. drive set up, the lower radiator hose will work but not so easy to get just right.
The P/S pump hoses bolted right onto the P/S box.
I used an Edelbrock electric fuel pump designed for low pressure for carbs. No regulator needed.
Passenger car oil pan. The rear of the pan will require a bit of extra sealant.

Headers were not a problem. This is a 300hp engine all day long.
Camshaft later.
 
Wow this is really a doable swap for me. I didn’t think the headers would fit at all but if they will it’s a game changer for me. Even if I have to do some grinding!
 
I didn't see if you were running a 4-speed or automatic.

If 4-speed, make sure crank in 360 is drilled properly for bearing and input shaft length of 4-speed transmission.

Also, you may need cam eccentric to drive fuel pump if you want to stay with a mechanical one.
 
Pull the magnum heads off and put them on the 340. Best of both worlds!
 
340inabbody said:
Are they compatible? I’ll need a new cam for sure if I did. I need to recam the 340 anyway.
Click to expand...
Magnum heads have rocker oiling through the lifter/pushrods instead of through block and head passages like the LA.
It can be done if you use lifters and pushrods (custom length, too) that have the oil holes. Then you will have to get a Magnum-specific 4 bbl. intake (unless you get heads drilled for the LA pattern or have it done) and throttle linkage, and then compensate for the different 1.5 (LA) vs 1.6 (Magnum) rocker ratios when selecting your camshaft.
 
If the block is at stock height and the heads uncut, the pushrod length should be at or very close to 7.250. That’s close enough for minor variations in head gasket thickness. IIRC, that’s the length the MP parts catalog used to sell.
 
If you have the stock style Magnum heads and 340/360 headers there's a port mismatch and you will have a huge exhaust leak.
Can't say that's true for all headers but best to measure first.
 
bobscuda67 said:
If you have the stock style Magnum heads and 340/360 headers there's a port mismatch and you will have a huge exhaust leak.
Can't say that's true for all headers but best to measure first.
Click to expand...
Hooker Super Comps @ 1-3/4 tube for E & B bodies fit and work perfectly.
 
I've done a couple of magnum head to LA block swaps.... Not that hard
 
I'm pretty sure that most of the lifters these days will provide oil to pushrods too.
 
Mean416 said:
I'm pretty sure that most of the lifters these days will provide oil to pushrods too.
Click to expand...
It’s true, actual “MoPar” lifter are hard to find. Because they don’t oil through the pushrod. The industry simply see an AMC lifter.
Works for me.
 
rumblefish360 said:
It’s true, actual “MoPar” lifter are hard to find. Because they don’t oil through the pushrod. The industry simply see an AMC lifter.
Works for me.
Click to expand...
I wonder how much oil pressure loss they cause in non oil through applications?
 
I’ve never had or heard of a problem but that’s an interesting thought. That and the massive holes feeding the lifters from the gallery. The oiling system is addressed in the engines book once you start turning what MP considered high rpm. In which it would be high rpm for the stock system and not what others think high rpm is. IIRC this morning, MP said 6K?
 
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