5.9 Magnum Torque motor build?

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MoparTrucker

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I have a 1983 dodge d150 4wd 4 speed has the 318 ALL stock. I'm wanting to make a low end torque grunt street vehicle on a $2,000 budget. I've talked about it and thinking about swapping out to a 5.9 Magnum.

On the 5.9 Magnum I want to know what I can do to get more lower end torque abstaining from a stroker build? how much can the rear and trany take?
 
I have a 360 LA motor with Magnum style heads by EngineQuest that wer prepped by IMM Engines in Indio, CA and the engine was dyno'd at about 438 lbs of torque around 2,500 RPM (I'll have to look at the graph to be 100% sure on that but definitely more than 400 lbs). But my build was more than 2,000 bucks.

What you need is a good heads, decent compression, good intake, and a decent cam. You don't have to go too big on cam either. Arguably, you'll be able to get a better cam since the Magnum block uses a roller cam. What you want to do is doable, but I think you need to expand that budget.

As far as budget goes, it also depends on what parts you have on hand already. Also, you need to determine what front cover you're going to run. Are you going to run the LA style front timing cover, or Magnum style with the serpentine belt and accessories?

Are you going to use actual Magnum heads? Remember those have a different intake bolt pattern are are limited to either the factory EFI intake, a CrossWind Air-Gap style dual pattern intake, or the Edelbrock Air-Gap Magnum intake. You can do like I did and run the EQ Magnum heads with the LA intake bolt pattern and use typical LA intakes. I believe my heads were about $1,500 bucks (give or take). That right there eats up most of your budget.

You can find more information here: Magnum Swaps
 
I have a 360 LA motor with Magnum style heads by EngineQuest that wer prepped by IMM Engines in Indio, CA and the engine was dyno'd at about 438 lbs of torque around 2,500 RPM (I'll have to look at the graph to be 100% sure on that but definitely more than 400 lbs). But my build was more than 2,000 bucks.

What you need is a good heads, decent compression, good intake, and a decent cam. You don't have to go too big on cam either. Arguably, you'll be able to get a better cam since the Magnum block uses a roller cam. What you want to do is doable, but I think you need to expand that budget.

As far as budget goes, it also depends on what parts you have on hand already. Also, you need to determine what front cover you're going to run. Are you going to run the LA style front timing cover, or Magnum style with the serpentine belt and accessories?

Are you going to use actual Magnum heads? Remember those have a different intake bolt pattern are are limited to either the factory EFI intake, a CrossWind Air-Gap style dual pattern intake, or the Edelbrock Air-Gap Magnum intake. You can do like I did and run the EQ Magnum heads with the LA intake bolt pattern and use typical LA intakes. I believe my heads were about $1,500 bucks (give or take). That right there eats up most of your budget.

You can find more information here: Magnum Swaps

So far my inventory is at 0 I have none bought yet. On heads I was thinking about the 302 swirl ports? I knew aftermarket heads would really use up the budget so I thought about used heads and port them if that's a good idea? Then cam advance? I plan on using the stock front end if that dosnt harm anything, I planned on buying a complete engine and adjusting what needs adjusted to get it installed if that dosnt harm anything?
 
Buy a good running magnum 360 throw on an AirGap intake,carb and a re-ground cam. I can’t think of a way to build a better small block Mopar on a $2000 budget
 
Buy a good running magnum 360 throw on an AirGap intake,carb and a re-ground cam. I can’t think of a way to build a better small block Mopar on a $2000 budget
Getting one with 90,000 miles for 200$ herein Phoenix. Hope you can find them cheaper. Some people are delusional with the prices they’re asking.

Jake
 
With the swap what do I need to be expecting? What parts should I expect to buy and how much will I be spending to swap it? With any budget left over what are some suggestions for more low end torque power performance parts? Also should I run stock cam if I do cam advance?
 
With the swap what do I need to be expecting?
Expecting as far as what?

What parts should I expect to buy and how much will I be spending to swap it?
After you have the 5.9 in hand, I suggest the following parts:
Car oil pan, new oil pump and car pick up.
Exhaust - manifolds? Customs piping, check TTI web site.
Headers, go to Summit racing and shop for headers. Then ether a diy dual exhaust @2-1/2 inches or custom job.
Induction; Edelbrock RPM, 600 cfm carb
Ignition; vacuum advance distributor and a chrome box, wiring harness and ballast resistor.
Air cleaner

Have a great day

With any budget left over what are some suggestions for more low end torque power performance parts? Also should I run stock cam if I do cam advance?
Leave the cam alone.
Leave the 302 heads alone. They don’t bolt up!
You’ll have plenty of torque.
 
Expecting as far as what?


After you have the 5.9 in hand, I suggest the following parts:
Car oil pan, new oil pump and car pick up.
Exhaust - manifolds? Customs piping, check TTI web site.
Headers, go to Summit racing and shop for headers. Then ether a diy dual exhaust @2-1/2 inches or custom job.
Induction; Edelbrock RPM, 600 cfm carb
Ignition; vacuum advance distributor and a chrome box, wiring harness and ballast resistor.
Air cleaner

Have a great day

Leave the cam alone.
Leave the 302 heads alone. They don’t bolt up!
You’ll have plenty of torque.

Edelbrock RPM or Edelbrock Air-Gap for Magnum?

Intake options for Magnum heads (just to clarify):
  1. RPM Air-Gap Magnum Intake Manifold for S-B Chrysler w/ Magnum Heads 318-360
  2. Small Block Mopar V8 Crosswind Intake Manifold Polished
  3. 55026 - Small Block Mopar V8 Crosswind Intake Manifold Satin
The last two are dual bolt pattern to fit either LA heads or Magnum heads. The first, is only for Magnum heads.

There's also Mopar M1 intakes with the Magnum bolt pattern, but they are no longer in production so hard to find.

But pretty much everything @rumblefish360 mentioned is right on the money.
 
Hes putting it in a truck, no need to swap oil pans or oil pump pickups. And he could even use his original exhaust manifolds, although the magnums are better
 
Hes putting it in a truck, no need to swap oil pans or oil pump pickups. And he could even use his original exhaust manifolds, although the magnums are better

So... low mileage junk yard motor and the rear sump truck oil pan and stock magnum truck exhaust manifolds. Switch to a carb intake. Install a Mopar electronic distributor, MSD distribitor, or HEI distributor.

Hey @MoparTrucker does your truck have Air Conditioning? If so, and if you want to keep it then you'll really need to go with the Edelbrock Air Gap Magnum intake because as far as I know it's the only one that will allow you to keep the stock Magnum engine A/C compressor.

If you're pulling the engine from a wrecking yard, take the A/C lines that go to the compressor. You'll have to adapt it somehow to your stock A/C lines. There's a guy on there that did it. I believe he has Barracuda with a complete Magnum engine and adapted the A/C compressor lines. He's actually a local guy and I've seen his setup up close. It's pretty sweet!

If you don't have A/C then start looking for the non-A/C alternator bracket usually found on Dakota's with a Magnum V6 engine. Then you can use the lower cost intake alternatives (I picked one up this past weekend at the Spring Fling swap meet).
 
keep it simple
get the flywheel for the magnum balance and get the motor in the truck
see where the manifolds dump
if in the wrong place--Usually interfering with steering on drivers side, maybe clutch linkage- you can use Jeep manifolds which dump at a different place
 
You can get a reground roller cam with a torque building profile for about 150.00 from Oregon Cam Grinders.
You can use the OE roller lifters and rockers with it also.
 
5.9 already comes with about a 197@50 torque cam
save your money for later forget roller rockers- just do a new chain
ask dart19666 on this board
I would think max would be about 260@.006 128@200 with about 530 lift that's about 10 degrees bigger @50 --
but no way would I pull the trigger about moving torque curve up without some road miles on the stock cam
cuz you have to dial in the valve train- new springs -etc
 
So... low mileage junk yard motor and the rear sump truck oil pan and stock magnum truck exhaust manifolds. Switch to a carb intake. Install a Mopar electronic distributor, MSD distribitor, or HEI distributor.

Hey @MoparTrucker does your truck have Air Conditioning? If so, and if you want to keep it then you'll really need to go with the Edelbrock Air Gap Magnum intake because as far as I know it's the only one that will allow you to keep the stock Magnum engine A/C compressor.

If you're pulling the engine from a wrecking yard, take the A/C lines that go to the compressor. You'll have to adapt it somehow to your stock A/C lines. There's a guy on there that did it. I believe he has Barracuda with a complete Magnum engine and adapted the A/C compressor lines. He's actually a local guy and I've seen his setup up close. It's pretty sweet!

If you don't have A/C then start looking for the non-A/C alternator bracket usually found on Dakota's with a Magnum V6 engine. Then you can use the lower cost intake alternatives (I picked one up this past weekend at the Spring Fling swap meet).

I don't use AC a whole lot and it's need recharged, porbably wont worry about it tho..
 
Expecting as far as what?


After you have the 5.9 in hand, I suggest the following parts:
Car oil pan, new oil pump and car pick up.
Exhaust - manifolds? Customs piping, check TTI web site.
Headers, go to Summit racing and shop for headers. Then ether a diy dual exhaust @2-1/2 inches or custom job.
Induction; Edelbrock RPM, 600 cfm carb
Ignition; vacuum advance distributor and a chrome box, wiring harness and ballast resistor.
Air cleaner

Have a great day


Leave the cam alone.
Leave the 302 heads alone. They don’t bolt up!
You’ll have plenty of torque.

Thanks
 
If the stock magnum exhausts dump the wrong place would your current exhaust fit till you figure out something better?
As I said Jeep 5.2-59 are different than Ram or Dakota IDK about Durango
 
Oh, one other thing... If you keep the Magnum front cover, you will NOT have a provision for a mechanical fuel pump. Just something to keep in mind.
 
If the stock magnum exhausts dump the wrong place would your current exhaust fit till you figure out something better?
As I said Jeep 5.2-59 are different than Ram or Dakota IDK about Durango

Yeah the manifold i have now could probably just bolt on

Oh, one other thing... If you keep the Magnum front cover, you will NOT have a provision for a mechanical fuel pump. Just something to keep in mind.

oh okay that would be sweet
 
Yeah the manifold i have now could probably just bolt on

oh okay that would be sweet

If you need a mechanical fuel pump, then you need to change the front cover to an LA style which means you'll need the LA water pump, crank pulleys, as well as the LA style alternator and power steering if you have power steering.
 
If you need a mechanical fuel pump, then you need to change the front cover to an LA style which means you'll need the LA water pump, crank pulleys, as well as the LA style alternator and power steering if you have power steering.

okay, its not a big deal if i do i do have all the front end
 
If you need a mechanical fuel pump, then you need to change the front cover to an LA style which means you'll need the LA water pump, crank pulleys, as well as the LA style alternator and power steering if you have power steering.

Which also dictates the cam type needed.
I knew I was going electric fuel pump, so I ordered the cam without the eccentric option.
There is a kit for the magnum cam that allows to add the eccentric for the mechanical fuel pump when using the LA chain cover.
 
lots of options
IDK if LA ex manifolds are a direct bolt on or not- anyone done it?
adapter plates needed? IDK just raising a potential gotcha
 
lots of options
IDK if LA ex manifolds are a direct bolt on or not- anyone done it?
adapter plates needed? IDK just raising a potential gotcha

I am running LA headers and gaskets on my Magnum, so I would have to say they do.
Since we know the spacing and bolt pattern are the same, then the only real difference I have seen is that the Magnum head has a slightly tapered edge on the two center exhaust ports that have no affect on fitment or sealing.

Check this out if you want to see the ports side by side so to speak.
#2---Magnum & LA Heads
 
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good to know- that's what I'd heard but not from someone who had done it
Easier to pick up HP at a higher RPM with the 318 rebuild option but harder to pick up as much grunt torque as 40 cu inches, a little more compression and a short roller cam does
And IMHO the 5.9 is just a better engine
 
Agreed. Another option i heard was using the low compression boosting the 318?? If I went with that I'd hate taking the engine apart just to regap the rings. New cam, springs, ring gap and call it? What are some thought on that
 
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