Magnum swap

[MoparMedic91]

Hey guys, I know this gets asked a lot but I'm new to the forum. I was wondering how difficult it would be to take a fuel injected mangum 5.2/5.9 and place it in my '83. My '83 is currently 318 w 4 speed manual. I want to run the fuel injection on it. I was also curious about the clutch set up as well. Would the 318 clutch work on it if I did put 5.9 in its place? Ive done similar swap in my '86 but it was carbed and auto.

 

[reek]

I'd go 5.9 over 5.2 if you have the choice, it's essentially the same swap. The transmission should bolt right up to the magnum.

biggest thing to do would be to add a fuel pump with enough pressure for the EFI as well as a return line if you don't have one. you could add an in line pump as this would be easiest. I got a tank off an EFI truck, it was a bigger one so that was an added bonus.

The ignition would be the other hurdle. you would need the ECU for the motor.

a much easier way would be to just add a bolt on EFI if you're just after EFI. Fitech or Holley ****** would be my recommendation. if @crazzywolfie chimes in he'd have more info as he has done the Fitech.

 

[crazzywolfie]

i don't know if a magnum fly wheel would work with the older style clutch setup but if you want a magnum MPFI setup you would likely need the magnum flywheel. you can purchase hotwire kits and get a pcm programmed to work with the setup if you want but it is not really cheap.

i don't have that much experience with my fitech. had the cam wipe a lobe or something and haven't got around to fixing it. was thinking about swinging it onto my elcamino but haven't got around to it yet. if you do go fuel injected don't buy a inline pump or at least not the fitech one. go for in tank pump. heck even a stock fuel injection fuel pump off almost any 90's vehicle should likely put out enough fuel pressure to run fuel injection.

 

[EvilSpirit]

Welcome to the forum.

I don't think that 5.2 and 5.9 flywheels interchange due to balance issues.

Even if they would, you also will have an issue with the crank trigger - it bolts to the back of the block and reads the flywheel through a hole in the top of the bellhousing that will not be there on your '83 bellhousing. It would be a good time to consider swapping in the Mag's 5 speed trans too. The ECM will also need to see a pulse from a VSS that you may not be able to get from your 4 speed.

Not sure if a fuel return line is necessary - in 1994 they went to a single line fuel system regulated at the pump. My 94, 96, 97, 99 and 02 Mag engines all used single line systems.

The OEM computer would work fine for stock engine. If you want to do any mods, like a cam, I'd go to a self tuning aftermarket EFI.

Hope this info helps.

 

[MoparMedic91]

I'm prolly just gna go w carb and put manual style timing chain cover on so I can do mechanical pump. That would possibly be simplest scenario. I was just curious.

 

[MoparMedic91]

This is a clip of my '86. It has 5.9 from 99 ram. It has big cam and a lot of headwork done to it.

 

[crazzywolfie]

i would recommend going electric fuel pump even if you go carbed. keep the timing that comes with the magnum so you can keep the higher amperage alternator and serpentine belt setup it has. it would also even give you the ability to upgrade to even higher amperage alternator in the future if you wanted. 90 amp alternators were pretty common on the magnums which is better than the 65 amp ones you usually find on the older trucks.

 

[MoparMedic91]

Would the newer style alternator work with current voltage regulator or would I need to change?

 

[crazzywolfie]

yup it all hooks up the same. dodge is at least good about that

 

[MoparMedic91]

Awesome thank you. You just made my life a lot simpler.

 

[EvilSpirit]

I'm prolly just gna go w carb and put manual style timing chain cover on so I can do mechanical pump. That would possibly be simplest scenario. I was just curious.

Not sure it's that simple. Mag engines have different cams with shorter noses and timing chains to fit under the shorter cover. I don't know if anyone makes an adapter to run a fuel pump eccentric on a Magnum cam.

 

[reek]

i don't know if a magnum fly wheel would work with the older style clutch setup but if you want a magnum MPFI setup you would likely need the magnum flywheel.
i don't have that much experience with my fitech. had the cam wipe a lobe or something and haven't got around to fixing it.

didn't even think about the flywheel. was just thinking bolt pattern.

didn't know about the cam issue, must have missed this part of the story. hope it works out.

 

[reek]

Not sure if a fuel return line is necessary - in 1994 they went to a single line fuel system regulated at the pump. My 94, 96, 97, 99 and 02 Mag engines all used single line systems.

was thinking if changing to an EFI tank for the pre 93 trucks, there are provisions for a return line. but yeah, no return line is a lot less work.

 

[reek]

if you end up with a newer Magnum, the voltage regulation occurs through the ECU. you can however 'retro fit' the newer units and use your current external regulator with some re-wiring. Don't know if I'm allow to link to a different site, but there's a great write up on another forum. you can PM me if you want the link.

 

[crazzywolfie]

didn't know about the cam issue, must have missed this part of the story. hope it works out.

i don't know if i have really mentioned it too much since i really don't know if it is worth repairing or not. been thinking about just replacing the truck with how much work it needs. i got a used cam and set of lifters i was thinking about taking the gamble but may be a waste of gaskets. i do got all parts needed to fix the engine. now the body on the other hand is beyond saving lol.