Getting Ready for the Magnum Swap. (help?)

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BigWhi

BigWhi

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So I am trying to get a parts list together and trying to figure out how much I need to save to do this swap. I already have a 5.9 Magnum engine and 518 Transmission pulled out of a 96 Dodge 2wd truck. Any help or advice will be appreciated.

1971 Plymouth Scamp "I just want a cruiser"

This was a /6 Scamp but I have a 73 parts car that has V8 K-member and disc brakes that I will be rebuilding and swapping in.

List of parts and estimated prices
1. Intake RPM Air Gap $350.00
2. Carburetor "Not sure what to buy on this one"
3. Oilpan "Not sure what is best/cost efficient on this as well.
4. Distributor "Not sure on this one either"
5. Headers "There are so many different opinions on this I'm lost"

I'm not a mechanic but my best friend who is helping me is. I'm just trying to get as much information as possible on what I need to buy before we get started. I have read so much that it just gets confusing on what is the best way to do things.

38471075_2165301280425253_4878152996426350592_n.jpg
 
OH, man there are so many variables in that.
Things like ignition, carburetion and headers have so many possibilities it endless.

There's throttle body injection.
Port fuel injection.
Then straight carburetion for some basic answers on that subject.

Then there's EFI controlled timing. (physically locked out electronically controlled distributors)
Distributors with and without vacuum advance.
Capacitive discharge and HEI ignitions.

If you want to keep it basic and run a standard ignition and carburetion (called naturally aspirated) you can run a standard type electronic (factory style) distributor and some sort of HEI style ignition. or MSD box.
Or even one of the many styles of home made high powered ignitions, like you have probably seen on here that guys have done WAY cheaper than off the shelf branded parts.

A basic 5.9 can be done pretty inexpensively carbed with an electronic distributor.

Make sure to keep or get a compatible flywheel/flex plate to mate the 5.9 to your 518.
The factory 5.9 flex plate works just fine.
A carb in the 600 to 750cfm range works. (600 being a hair on the small side, but gets decent mpg)

You will for sure be doing some floor cutting for that 518, and you need to consider how to you want OD and lockup controlled.
There are aftermarket computers for this but they aint cheap.
An automatic shifting system controlled by the governor in the trans can be built at home a lot cheaper.

Just a ton of options are available, so I would start by deciding the basics first.
Carbed or EFI?
Basic OEM style ignition or spend hundreds on something else?
Electronic or physically (distributor) controlled timing?

Then we might be able to narrow down the choices for you.
 
Your transmission is probably not a 518, more likely it's a 46RE and is electronically shifted by the PCM. Might want to check into that
 
TrailBeast said:
OH, man there are so many variables in that.
Things like ignition, carburetion and headers have so many possibilities it endless.

There's throttle body injection.
Port fuel injection.
Then straight carburetion for some basic answers on that subject.

Then there's EFI controlled timing. (physically locked out electronically controlled distributors)
Distributors with and without vacuum advance.
Capacitive discharge and HEI ignitions.

If you want to keep it basic and run a standard ignition and carburetion (called naturally aspirated) you can run a standard type electronic (factory style) distributor and some sort of HEI style ignition. or MSD box.
Or even one of the many styles of home made high powered ignitions, like you have probably seen on here that guys have done WAY cheaper than off the shelf branded parts.

A basic 5.9 can be done pretty inexpensively carbed with an electronic distributor.

Make sure to keep or get a compatible flywheel/flex plate to mate the 5.9 to your 518.
The factory 5.9 flex plate works just fine.
A carb in the 600 to 750cfm range works. (600 being a hair on the small side, but gets decent mpg)

You will for sure be doing some floor cutting for that 518, and you need to consider how to you want OD and lockup controlled.
There are aftermarket computers for this but they aint cheap.
An automatic shifting system controlled by the governor in the trans can be built at home a lot cheaper.

Just a ton of options are available, so I would start by deciding the basics first.
Carbed or EFI?
Basic OEM style ignition or spend hundreds on something else?
Electronic or physically (distributor) controlled timing?

Then we might be able to narrow down the choices for you.
Click to expand...

Yes, I really want to keep it basic. I figure the distributor and msd would be the way to go.

Also, I was thinking about just trying to find a 904 to use instead of the 518 because I really didn't want to cut any more than I have to. We are already replacing the roof skin and patching a floorboard, so I really don't want to get into any more body work than I need to lol.
 
replicaracer43 said:
Your transmission is probably not a 518, more likely it's a 46RE and is electronically shifted by the PCM. Might want to check into that
Click to expand...

Yep, 96 was the change year.
It could be either a 46RH (A518 hydraulic) or a 46RE (A518 Electronic)
The RE versions MUST have a computer, either aftermarket or OEM.
I almost missed that completely, thanks.

BigWhi said:
Yes, I really want to keep it basic. I figure the distributor and msd would be the way to go.

Also, I was thinking about just trying to find a 904 to use instead of the 518 because I really didn't want to cut any more than I have to. We are already replacing the roof skin and patching a floorboard, so I really don't want to get into any more body work than I need to lol.
Click to expand...

The 904 would bolt right up to the Magnum, or you could go with a 95 and down A500 (42RH) and that would take minimal mods and give you OD and lockup. (which is really nice to have for a driver car)

A holley or Edelbrock 700-750 would be a nice match, as would an MSD distributor and ignition if the budget allows.
There are also, as I mentioned some pretty nice DIY HEI conversions out there as well that work great with the OE small block distributor (which fit the Magnum perfectly)

One other thing to pay attention to is that the Magnum is a truck motor and has a mount boss on the drivers side of the block that can interfere with some brands of headers when installed in a car.
It's a lot easier to trim it off before the headers are in the way.

I think it was this one, and the small red line would be the cut.
A cutoff wheel on a 4" grinder gets it done pretty quick.

5.9Block.JPG
 
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Before you spend a lot of money on this engine, I would suggest having the cylinder heads checked first. BTW, TTI is a great choice for headers for this motor/body combo.
Good luck with your project and keep us posted.
 
BigWhi said:
1971 Plymouth Scamp "I just want a cruiser"

2. Carburetor "Not sure what to buy on this one"
3. Oilpan "Not sure what is best/cost efficient on this as well.
4. Distributor "Not sure on this one either"
5. Headers "There are so many different opinions on this I'm lost"

View attachment 1715213818
Click to expand...

I'm at about the same step of the process for my 72 Dart.

For a carb, you can pretty much go with your choice of most any carb in the 650 - 750 CFM range. Most people have a preference for either Holley or Edelbrock, and will pick accordingly. If you are looking to save some $$$ (who isn't?), used is always an option, but you might be buying someone else's headaches or mistakes. One option is to buy a refurb factory direct from Holley, which sells them on eBay (for example: Holley 0-83670 670CFM Factory Refurbished Aluminum Street Avenger 4bbl | eBay). Another option is buying from a reputable rebuilder like EDELBROCK 750 CFM CARBURETORS - I've bought from both of these vendors for other projects and both times it worked out great.

For an oil pan, you just need an LA small block 360 mid-sump pan and pickup that fits your car. If you are using the Magnum timing cover, you can use the Magnum oil pan gasket with an LA pan. You can go with a junkyard pan or a cheap aftermarket pan, but a lot of people report fitment and sealing issues with the $50 - $60 cheapies, like the Summit house brand stuff. But they do work.

Distributor is super easy. Most any LA small block distributor will work. You can go with a junkyard, used, or re-manufactured unit, a Chinese knock-off, or spring for the big-name stuff.

For headers, you just need LA small block headers that fit your car. TTI and Doug's generally have the best reputation for fit, but you can make most anything work with sufficient determination.
 
I really appreciate the information you guys are giving me.
 
67Dart273 said:
??? 46R is an A518
Click to expand...
Let me help you out..... the A518 came out about 88, and was made till about 94 or 95. It is hydraulically shifted, You have the 46RH, which is essentially the same, and then you have the 46RE, which is electronically shifted
 
BigWhi said:
List of parts and estimated prices
1. Intake RPM Air Gap $350.00
2. Carburetor "Not sure what to buy on this one"
3. Oilpan "Not sure what is best/cost efficient on this as well.
4. Distributor "Not sure on this one either"
5. Headers "There are so many different opinions on this I'm lost"
Click to expand...
Sorry I’m late to the thread but this is what I did on my B body. I’ll make adjustments for the A body.

1 & 2: I did the same intake. Your carb choice should be in the 600 - 650 cfm area. I used an AFB at first and then swapped to the Thunder AVS which was a tiny bit better for the secondary air door tuning BUT both worked excellent. Jet it, set it, forget about it. Clean the air bleeds once a year with carb cleaner at spring tune up time.

(But If a Holley is more of your style carb, a simple 4160/4150 - 600cfm carb will work just as well.)

Use the thick Edelbrock gasket under the carb to resist heat soaking and boiling the fuel in the carb.
A drop base air cleaner may have to be used. I went to Mancini Racing for a drop base for the ribbed MP filter.

While you could use a 750 carb, your stock engine, even if mildly cammed would be hard pressed to use it all. The smaller carb, I have found better for a driver/cruiser (even if some performance parts are sprinkled on the engine) because it retains a crisp throttle response and offers an edge in mileage due to the smaller primaries. Overall it gives up very little on the top end.

3: A standard oil pan will do the trick for a driver/cruiser.

4: A standard unit will do the trick or you can upgrade to a nicer unit like the one offered from Pace Performance. I use there “Ready to run” unit which is the same as MSD’s. But crazy cheaper.
Works excellent.

5: This is always a good question and a lot depends on the wallet. While standard headers of the normal style that have been in production half way to forever now, are cheap, I hate hate hate the issue of low ground clearance with 3 tubes going under the steering linkages.

Do yourself a huge favor and save for ether the Doug headers or the TTI headers. The nice thing about the TTI header company is they also have exhaust pipes from header to bumper that include Dyno Max Super Turbo’s. A very good muffler that is reasonable enough to cruise with and has a good sound when the power pedal is pushed.

I have the TTI headers and exhaust.

If the cheaper headers are used, fitting them could be a hammer denting fest or not. Quality control is low on the typical units. If cheap exhaust is also going to be done, AKA not a full exhaust, then a simple design and low cost option is just 2 lengths of 2-1/2 pipe @ 4 feet long cut down to size with 2 of your choice mufflers and hangers. I still suggest an “H” pipe to be used. There cheap at Summit or Jegs. EZ to install.

All parts listed are used and approved by the author.
 
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rumblefish360 said:
Sorry I’m late to the thread but this is what I did on my B body. I’ll make adjustments for the A body.

1 & 2: I did the same intake. Your carb choice should be in the 600 - 650 cfm area. I used an AFB at first and then swapped to the Thunder AVS which was a tiny bit better for the secondary air door tuning BUT both worked excellent. Jet it, set it, forget about it. Clean the air bleeds once a year with carb cleaner at spring tune up time.

(But If a Holley is more of your style carb, a simple 4160/4150 - 600cfm carb will work just as well.)

Use the thick Edelbrock gasket under the carb to resist heat soaking and boiling the fuel in the carb.
A drop base air cleaner may have to be used. I went to Mancini Racing for a drop base for the ribbed MP filter.

While you could use a 750 carb, your stock engine, even if mildly cammed would be hard pressed to use it all. The smaller carb, I have found better for a driver/cruiser (even if some performance parts are sprinkled on the engine) because it retains a crisp throttle response and offers an edge in mileage due to the smaller primaries. Overall it gives up very little on the top end.

3: A standard oil pan will do the trick for a driver/cruiser.

4: A standard unit will do the trick or you can upgrade to a nicer unit like the one offered from Pace Performance. I use there “Ready to run” unit which is the same as MSD’s. But crazy cheaper.
Works excellent.

5: This is always a good question and a lot depends on the wallet. While standard headers of the normal style that have been in production half way to forever now, are cheap, I hate hate hate the issue of low ground clearance with 3 tubes going under the steering linkages.

Do yourself a huge favor and save for ether the Doug headers or the TTI headers. The nice thing about the TTI header company is they also have exhaust pipes from header to bumper that include Dyno Max Super Turbo’s. A very good muffler that is reasonable enough to cruise with and has a good sound when the power pedal is pushed.

I have the TTI headers and exhaust.

If the cheaper headers are used, fitting them could be a hammer denting fest or not. Quality control is low on the typical units. If cheap exhaust is also going to be done, AKA not a full exhaust, then a simple design and low cost option is just 2 lengths of 2-1/2 pipe @ 4 feet long cut down to size with 2 of your choice mufflers and hangers. I still suggest an “H” pipe to be used. There cheap at Summit or Jegs. EZ to install.

All parts listed are used and approved by the author.
Click to expand...
Excellent real world response, Robert.
 
rumblefish360 said:
Sorry I’m late to the thread but this is what I did on my B body. I’ll make adjustments for the A body.

1 & 2: I did the same intake. Your carb choice should be in the 600 - 650 cfm area. I used an AFB at first and then swapped to the Thunder AVS which was a tiny bit better for the secondary air door tuning BUT both worked excellent. Jet it, set it, forget about it. Clean the air bleeds once a year with carb cleaner at spring tune up time.

(But If a Holley is more of your style carb, a simple 4160/4150 - 600cfm carb will work just as well.)

Use the thick Edelbrock gasket under the carb to resist heat soaking and boiling the fuel in the carb.
A drop base air cleaner may have to be used. I went to Mancini Racing for a drop base for the ribbed MP filter.

While you could use a 750 carb, your stock engine, even if mildly cammed would be hard pressed to use it all. The smaller carb, I have found better for a driver/cruiser (even if some performance parts are sprinkled on the engine) because it retains a crisp throttle response and offers an edge in mileage due to the smaller primaries. Overall it gives up very little on the top end.

3: A standard oil pan will do the trick for a driver/cruiser.

4: A standard unit will do the trick or you can upgrade to a nicer unit like the one offered from Pace Performance. I use there “Ready to run” unit which is the same as MSD’s. But crazy cheaper.
Works excellent.

5: This is always a good question and a lot depends on the wallet. While standard headers of the normal style that have been in production half way to forever now, are cheap, I hate hate hate the issue of low ground clearance with 3 tubes going under the steering linkages.

Do yourself a huge favor and save for ether the Doug headers or the TTI headers. The nice thing about the TTI header company is they also have exhaust pipes from header to bumper that include Dyno Max Super Turbo’s. A very good muffler that is reasonable enough to cruise with and has a good sound when the power pedal is pushed.

I have the TTI headers and exhaust.

If the cheaper headers are used, fitting them could be a hammer denting fest or not. Quality control is low on the typical units. If cheap exhaust is also going to be done, AKA not a full exhaust, then a simple design and low cost option is just 2 lengths of 2-1/2 pipe @ 4 feet long cut down to size with 2 of your choice mufflers and hangers. I still suggest an “H” pipe to be used. There cheap at Summit or Jegs. EZ to install.

All parts listed are used and approved by the author.
Click to expand...


Thank you so much for this information. I really appreciate it.
 
I love threads like this because it goes to show/prove how cheaply (and EASILY) you can stab a Magnum into an A-Body. This was my "Original" plan for my Swinger but then I got swifted away with the hopes/wants of a New Gen Hemi but at that cost point I then was attracted to the LS swap - so I have been torn. I want "NEW" or newer technology in the motor swap but as cost effective and least amount of cutting and fabrication as possible since I will be doing 90-95% of the work myself. and I "ALWAYS" come back to the Magnum Swap. Following your thread for more information - Keep up the good work.
 
@prican_2000

The Magnum swap is the most cost effective swap to do. However, the amount of power you want/need/desire, LOL, may not be an easily obtainable amount (big power wise) with a LA or Magnum. This is where the people do the LS or HEMI swap for the leg up on power production on stock equipment.

Obtaining 800 - 1,000 hp from an LA or Magnum with there stock components isn’t a wise maneuver.
:lol:

I did a Magnum swap into my ‘79 Magnum. It just required (for me and my route) a carb intake and a carb, headers were Hooker super comps, a stock distributor and a ignition which was a MP chrome box. I had everything laying around except the intake. Which require little. Just a drill and tap of one spot.

Oh! Almost forgot, the Magnum block, being it doesn’t oil through the heads for the rocker gear can be a stumbling block for some. You can convert to pushrod oiling ez enough. And at that point, it could be worth considering a head upgrade if your going past Edelbrocks Magnum heads ability. W2-W5....
 
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@prican_2000

The Magnum swap is the most cost effective swap to do. However, the amount of power you want/need/desire, LOL, may not be an easily obtainable amount (big power wise) with a LA or Magnum. This is where the people do the LS or HEMI swap for the leg up on power production on stock equipment.

Obtaining 800 - 1,000 hp from an LA or Magnum with there stock components isn’t a wise maneuver.
:lol:

"Magnum Swap is the most cost effective swap to do" - Is it really?!?!?!?!!?
When taking into account that you will have to replace the heads, if you go with the Hughes heads they're $1200!!!!

Which brings me to a question - are "ALL" the 5.9 heads prone to the hereditary cracking? or is this specific to certain years Magnum motors or head manufacturing number???????

But back to the cost effective swap statement - if you buy a 5.9 for approx. $500 then add the $1200 for heads and whatever other expenses to rebuild, gaskets etc addressing any "possible" issues before stabbing the motor in - that puts you in the $2K territory which is New Gen Hemi pricing (used 5.7). Am I missing something here?

^^^ That is mainly the reason why I have not bought anything yet or decided on which powerplant to go with. I am not looking for a Race Car - I mainly want a Cruiser with good street manners but still have a respectable HP. And I tell you what I have a 2006 300C that previously had a 5.7 with a mild Cam and that thing was AWESOME!!!! HP on demand (low 12s in the 1/4) and that was with a 4500lb Whale of a car - I cant imagine what that same power plant would do in a car that is almost half that weight. hmmmmmmmmmmmmm
 
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All the magnum heads are cracked, and it doesn't really matter, they still run 300k quite regularly around here. I've done about 10 magnum swaps over the years, buy at junkyard after hearing run, pop a carb intake on there, use the hughes engines cam snout extension, and done. Cheap, easy,
 
replicaracer43 said:
All the magnum heads are cracked, and it doesn't really matter, they still run 300k quite regularly around here. I've done about 10 magnum swaps over the years, buy at junkyard after hearing run, pop a carb intake on there, use the hughes engines cam snout extension, and done. Cheap, easy,
Click to expand...


well DAMN!!!! That's good to know, as I thought that once they cracked - they required immediate replacement. Thanks for the info
 
prican_2000 said:
well DAMN!!!! That's good to know, as I thought that once they cracked - they required immediate replacement. Thanks for the info
Click to expand...
Nope, there are 10s of thousands ram trucks, durangos, Grand Cherokees, and Dakota trucks running around with factory heads, no issue.
 
And in your junkyard 5.7 comparison, you forget it requires about a $1000-$1500 wiring harness and computer to make it running, crazy expensive headers, aftermarket oil pan and mounts ect. Ect. and LOTS of those 5.7s have camshaft and lifter failure...a magnum 5.2 or 5.9 can be done in a weekend easily
 
prican_2000 said:
@prican_2000

The Magnum swap is the most cost effective swap to do. However, the amount of power you want/need/desire, LOL, may not be an easily obtainable amount (big power wise) with a LA or Magnum. This is where the people do the LS or HEMI swap for the leg up on power production on stock equipment.

Obtaining 800 - 1,000 hp from an LA or Magnum with there stock components isn’t a wise maneuver.
:lol:

"Magnum Swap is the most cost effective swap to do" - Is it really?!?!?!?!!?
When taking into account that you will have to replace the heads, if you go with the Hughes heads they're $1200!!!!

Which brings me to a question - are "ALL" the 5.9 heads prone to the hereditary cracking? or is this specific to certain years Magnum motors or head manufacturing number???????

But back to the cost effective swap statement - if you buy a 5.9 for approx. $500 then add the $1200 for heads and whatever other expenses to rebuild, gaskets etc addressing any "possible" issues before stabbing the motor in - that puts you in the $2K territory which is New Gen Hemi pricing (used 5.7). Am I missing something here?

^^^ That is mainly the reason why I have not bought anything yet or decided on which powerplant to go with. I am not looking for a Race Car - I mainly want a Cruiser with good street manners but still have a respectable HP. And I tell you what I have a 2006 300C that previously had a 5.7 with a mild Cam and that thing was AWESOME!!!! HP on demand (low 12s in the 1/4) and that was with a 4500lb Whale of a car - I cant imagine what that same power plant would do in a car that is almost half that weight. hmmmmmmmmmmmmm
Click to expand...

I must be missing something. You just copied my post.
 
prican_2000 said:
well DAMN!!!! That's good to know, as I thought that once they cracked - they required immediate replacement. Thanks for the info
Click to expand...
Absolutely not. That is a misnomer. However, if the engine shows signs of heavy oil consumption, blow by, poor running, oil fouled plugs, overheating due to coolant loose, if it is the head, then the head is way cracked and needs to be replaced.

The head cracking issue is (relatively) well known.

If it is as bad as everyone makes it out to be, (and many never owned or opened up a Magnum engine, there just repeating wht they hear/read.) then my trucks heads are for surely cracked. I’m north of 260,000 miles but yet it runs absolutely fine. Good mileage, smooth running, no oil loses, inside looked good.
 
rumblefish360 said:
I must be missing something. You just copied my post.
Click to expand...

Sorry for some reason the board just attached my comments under your post and made it all seem as though it was your original post but if you read a lil lower - I made some comments.
 
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