La to Magnum parts list??

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j par

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I think I'm going to do a magnum serpentine setup on my truck project. It's going to have AC and power steering so I'll need everything for the most part...
I'll probably buy a new water pump and I will not connect the fan as I'll probably use an electric one...
I know I need the main bracket and I don't think I can use a mechanical fuel pump as I'm under the impression it will get in the way of something?.. put my biggest question to start with at this point is can I still use my la style timing cover?..
 
Also if anybody knows if the 4.7 has all the same serpentine stuff as everything else small block?..
 
Timing cover is different than LA and is required for the bracket. So if you want to run the serpentine belt, you need it all and will not be able to run a mechanical fuel pump.

Not absolutely certain, but pretty sure the 4.7 stuff has no relation to the LA stuff and nothing will interchange.
 
I think I'm going to do a magnum serpentine setup on my truck project. It's going to have AC and power steering so I'll need everything for the most part...
I'll probably buy a new water pump and I will not connect the fan as I'll probably use an electric one...
I know I need the main bracket and I don't think I can use a mechanical fuel pump as I'm under the impression it will get in the way of something?.. put my biggest question to start with at this point is can I still use my la style timing cover?..

I don't think so. The LA cover doesn't have the mounting bosses for the serpentine belt system. Also, I believe oil pan gaskets are different .
 
I should add that the cover is not just different in that it has mounts for the bracket, but the water pump is reverse rotation so the water pump mount area is completely different as well.

All or nothing.
 
Also, I believe oil pan gaskets are different .

Pan gasket is different but it's not related to the TC. The Magnum pan gasket is a one piece gasket and did away with the big rubber segment in the corner of the front seal where you pull the nipple through the pan to hold it in place. Because the Magnum gasket doesn't have that, it will not seal an LA oil pan unless you plan for it and fill it with RTV and you put it together.

Either way, the bottom of a Magnum timing cover is identical to an LA one in that area.

And FYI, all the water pump to block and TC to block bolt holes should line up as well.
 
Looks like the power steering pump will be an issue if you run LA heads. The Magnum heads have bosses that the LA heads do not that are used to mount the pump.

Not running PS is a bit of an issue as belt routing seems to be difficult without the pump. Don't think it is impossible, it would fix the issue with the lack of bosses on the heads. Just saying that it seems like there are difficulties with it.

There is also the issue of the tensioner as it bolts to bosses on the head that are missing on an LA head.

I've seen pictures of a kit by Magnum Mopars where they built a mount to put the tensioner over the top of the water pump. This would solve both issues with the missing bosses, assuming you want neither AC nor PS.

Just a heads up.
 
Forgot to mention that a 1991 Dakota with a V8 used a serpentine setup. Pretty sure the PS pump bracket bolted to the TC cover instead of the cylinder head in that setup.

Besides it being a one or two year only part, the belt routing and tensioner almost require that the smog pump is included. I tried to find a way to get rid of it on my Dakota, but gave up when it finally stopped squeaking. I found posts where people said they got rid of it, but I never found info on how.

And the tensioner is made of unobtanium so if they go out you are kind of stuck. I got lucky and found one in a JY that was still good when mine went bad.

I will check later today and verify that the pump does indeed bolt to the cover.

Just an idea.
 
Not worth it unless you buy a parts truck with everything.
 
I’m expecting to do this swap this winter at the same time I do a Magnum EFI swap and just realized that another issue with the Magnum serpentine setup is the fan. They use a screw on mechanical fan setup and have no option for the old style 4 bolt fan. Maybe the Magnum fan works? Or maybe this will require an electric fan.

Just something else to look into.
 
I’m expecting to do this swap this winter at the same time I do a Magnum EFI swap and just realized that another issue with the Magnum serpentine setup is the fan. They use a screw on mechanical fan setup and have no option for the old style 4 bolt fan. Maybe the Magnum fan works? Or maybe this will require an electric fan.

Just something else to look into.
That fan puts tremendous stress on the water pump and it's probably a great contributor to them going out.. I always use electric fans on everything now...
 
I’m expecting to do this swap this winter at the same time I do a Magnum EFI swap and just realized that another issue with the Magnum serpentine setup is the fan. They use a screw on mechanical fan setup and have no option for the old style 4 bolt fan. Maybe the Magnum fan works? Or maybe this will require an electric fan.

Just something else to look into.
'90-'91 Dakota.
43033-1_ANG_A__ra_p.jpg


It was a two- year only crossbreed between the old standard-rotation pump and the upcoming reverse-rotation Magnum pump.
 
'90-'91 Dakota.
View attachment 1715802147

It was a two- year only crossbreed between the old standard-rotation pump and the upcoming reverse-rotation Magnum pump.

Nice! I have a 1991 Dakota with the 318 and was familiar with similarities but never noticed that the water pump still used the 4 bolt mount. Just need the pulley to go with it.

For what it's worth, Ehrenburg used a thread-on mechanical fan on project Savvy Savoy so they must work as well.

Been reading back tech articles about some of this stuff and randomly saw that after I posted the issue. Ironically, in the same build, Ehrenburg checked to make sure the fuel pump eccentric fit under the Magnum TC cover, which is where I read that they do so many years ago.
 
Just need the pulley to go with it.
Pulley AND fan- remember, reverse rotation; LA fans might fit but won't work.
And it has to be paired with the Magnum-style timing cover- the revised inlet angle will interfere with the fuel pump/pump mounting boss on the LA style cover.
 
Also if anybody knows if the 4.7 has all the same serpentine stuff as everything else small block?..
Don't think so, I have an extra few magnum parts you will be needing. Actually probably everything &. Harness for mpfi if needed
 
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