5.9 Magnum Dart

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Sinister.

Sinister.

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I've been looking into this for a while but want a little bit more information before I make a purchase.

I am keeping the fuel injection, as well as the serpentine belt and I'm going to couple it to a 727.

What will I need to complete the swap? Any special motor mounts, manifolds, etc?

Parts list:
5.9L Magnum Intake to pan, wiring harness, and computer
360 Torque Converter
High volume fuel pump and fuel lines
Radiator w/ electric fans
 
I can't help you on the FI or Serpentine part, your on your own there lol, but you'll need a drivers side 360 A body Mount, a 360 car oil pan, i just did this swap, but went carb'd, i went with the summit headers & manual steering.
 
first off thanks for the help, i appreciate it. What passenger side motor mount will i need? I need the LA 360 pan but the magnum gasket, correct? Do they make headers that work with power steering? Or could i reuse the headers on the 318 in the car?
 
I am thinking about doing the same swap, non-EFI to start, into a 71 Scamp. I have small chamber 360 heads, a center sump pan to clear the K member on the Scamp and have 340 exh manifolds on the 318 now - wondering if they will transfer to the magnum head? I suspect not based on the bolt ex patterns on the heads...

Othewise I am looking for headers too
 
The summit headers are the best bang for the buck, i was really surprized how well they looked for a cheap header with nice solid construction, Keeping the PS will limit the fitment i'm sure, at least on the earlier "bisket" style mounts, you can re-use the pass side 318 mount, Sinister, you need to run the LA oil pan gasket with the LA pan, what year is this dart? Octanejunkie, i don't know if the manifolds will fit.
 
it's a 72. K-frame is out of a 73 and I have an assortment of motor mounts.
 
Semi-local junkyard quoted me $500 for engine, harness and computer, what do you think?
 
Too much, unless you here it run & it basically has no major issues, i will tell you this, I'll garuantee the heads are cracked, ALL of the 360 magnum heads crack between the valve seats, its a given, but that doesn't mean they've hit water yet, you take a chance on all these used 360 magnums, it sucks, how many miles are on it, & does it run??

Now from what i've heard, the FI intakes "suck" big time, the cam is poo-poo, IMHO, i'd just convert it over to run a carb., by the time you run all that wiring for the computer, you may not be too impressed with the results, & if you plan on any gears, forget about the cam/intake, they are gone at 4000 rpm, If you were close to me, i'd say once you hook up all the EFI set-up, i'de run you heads up against my carb'd magnum, i'll bet i'd win lol.

Not trying to discurage you in any way, i only have alittle over 1800.00 in mine, & thats with a "brand new" set of RHS Indy heads, re-ground cam, Crosswind RPM intake, i'm very-very impressed with this 360 magnum for a basic build with a stock bottom end, can't wait to get the gears installed, i'm going from 2.76s too 3.73s, i'm sure it'll wake it up, but it flies at it is now.
 
idk but unless its a 5.7 hemi i wouldnt waste your time doing efi swaps just my .02cents or if you wanna get frisky get a 6.1 theres a dart on here thats done it so it can be accomplished
 
My issue is gas mileage. I'm going to college next summer and will be regularly driving 150 miles a week and my current 12 or so combined mpg isn't going to cut it. As far as power goes, it should be just about where the 318 in my car is and that is fine.

As for the hemi, money IS an issue, so much that I could not possibly afford to do a 5.7L swap
 
I've been going thru a lot of head scratching about EFI as well. From what I can gather, the OEM EFI is not a very friendly setup. Might be better and easier to look at a megasquirt box. As to mileage and power, well, that 5.9 Magnum will run circles around your 318. 12 mpg sounds pretty thirsty. Years ago, I had a '71 360 2bbl in an A body and I could get high teens for mileage if I kept my foot out of it.
 
the 318 is a mild street build so it sucks a bit more gas ;)

I haven't heard much about the difficulty of the OEM EFI. In the future I do plan on going to a megasquirt system but I do now have the funds and the OEM EFI will be a functioning setup so I think it will be work the hassle
 
If you have a 318 thats only getting 12 mpg,then the 5.9 is gonna get 8mpg.The .030 318 in my dart gets about 16mpg or better,and it has somewere around 350-375hp.Your combination of parts must be off somehow.The magnum motors are even worse on gas.A 318 can be very efficient on gas,with the right combination of part,close to 30 mpg if you keep your foot out of it,and just cruise.My 73 charger se,with a 86 318,summit headers,eddy performer intake,and 600 holley got 28 mpgs on a trip.It had a 727,8.25 rear with 2.76 gears and was a heavy car for a 318,but felt pretty peppy to be so good on gas.The 302 casting heads are very efficent cylinder heads for gas milage.
 
Sinister, i'll agree, if your 318 is only getting 12 mpg, then something is way off, they'll pull 22-24 pretty easy on a good tune, 360s can push upper teens, but you'll sacrafice Performance abit, unless you spend $$$ & get a good computer, the stock computers for those 360 magnums are tuned for the Dakodas/Rams/Durangos @ there weight/gearing, alot different from a dart, i'm sure you know that you'll need a high pressure fuel pump too, don't know how tight your funds are, but i'm sure theres more involved in this swap then meets the eye, & your pocket will run dry quik. Do you have a base $$ of what your willing to spend on doing this?
 
JoeDust451 said:
...I'll garuantee the heads are cracked, ALL of the 360 magnum heads crack between the valve seats, its a given, but that doesn't mean they've hit water yet, you take a chance on all these used 360 magnums
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That's exactly what my motor shop guy told me when I dropped my magnum heads off for a check up, turns out mine are NOT cracked, yet, and after $200 worth of love and kindness are ready to bolt on and go.

Now from what i've heard, the FI intakes "suck" big time, the cam is poo-poo, IMHO, i'd just convert it over to run a carb., by the time you run all that wiring for the computer, you may not be too impressed with the results
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Look at the bolt on EFI solutions from retrotek and FAST, both are very similar and are soup to nuts solutions for around $2000 complete, less the return line you have to run, I am putting a Powerjection+ Plus in my truck when it comes out and possibly one on my 71 Scamp too - they are self-tuning and set up their own base maps, and computer tuning of the fuel and spark curves is possible if you want to do it; though many guys don't and still get good results

Sinister. said:
My issue is gas mileage. I'm going to college next summer and will be regularly driving 150 miles a week and my current 12 or so combined mpg isn't going to cut it. As far as power goes, it should be just about where the 318 in my car is and that is fine.
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IME, gas mileage is determined by several factors, the first one is YOU. If you have good self control and can stay off the pedal and do 50 in the slow lane then you can get great gas mileage, otherwise it boils down to fuel delivery system efficiency, combustion/timning efficiency, gearing and environment.
 
Octanejunkie, you got VERY lucky on the heads, now are these mags off a 318 or 360? On that FI, i'm sure he doesn't have 2K to shell out for a "good" system, the factory set-up is just ok, i'm sure a carb'd set-up will run as strong if not better for alot less hassle & maybe even $$.
 
JoeDust451 said:
Octanejunkie, you got VERY lucky on the heads, now are these mags off a 318 or 360?
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The heads I got were off a 360, here are a few pics of them. As far as casting numbers, all I can find are "6671" so I have still to properly ID these heads, but the chambers do look aweful small, very similar to the vortec heads as another forum member pointed out
newfolder2146.jpg

newfolder2148.jpg

I do consider myself lucky in regards to these heads being sound, but I was guaranteed they would be...

Having new seals, a valve job and surfacing done then they go into storage for my future magnum 360 build - but first to figure out what I want from the motor

On that FI, i'm sure he doesn't have 2K to shell out for a "good" system, the factory set-up is just ok, i'm sure a carb'd set-up will run as strong if not better for alot less hassle & maybe even $$.
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Agreed, in the short term a carb is cheaper. In the long run, especially when 85 octane is the highest test we can readily get, $2K for bolt on EFI is going to look cheap once we are back to $5 a gallon and anything less than 25mpg is going to be painful and expensive - personally, I'll make the investment now and unlike a factory (read vehicle-specific) EFI solution, the aftermarket self-tuning systems can be easily moved from vehicle to vehicle using your the intake manifold of your choice
 
What is your total in those heads (honestly), i've got 930.00 (to the door) in my RHSs with alot of room to grow in the future, they flow 240/174 stock with 1.92/1.60 valves, tons of meat for milling & porting, they are heavy lol.
 
I have $1000 that I'm willing to spend... but I have another $2000 that I'm able to spend.

And like I said I do plan on going to a Megasquirt box in the future, but that will be a step I take after the engine is running in the car and I have more money.

Would there be a better transmission option over the 727?

I'm looking for reliability and efficiency on a budget.
 
Sinister. said:
I have $1000 that I'm willing to spend... but I have another $2000 that I'm able to spend.

And like I said I do plan on going to a Megasquirt box in the future, but that will be a step I take after the engine is running in the car and I have more money.

Would there be a better transmission option over the 727?

I'm looking for reliability and efficiency on a budget.
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If you're looking for efficiency then the 904 trans is the way to go. I have been told that the 727 uses up to 40 extra hp just to run. That would translate into a ton of fuel consumption. Plus, around town you might appreciate the shorter first gear ratio.
 
I agree with autopar3000, not sure if it'll chew up 40hp, but the 904 is much lighter, easier to install, has low 1st. gear, & can be built to handle some good HP without fail.

So your only wanting to spend 1000.00 at the momment, or are you willing to tap into the other 2K if needed? If your planning on getting a megasquirt down the road, i would just set it up for carb'd for now, then gather up (in time) all the stuff to convert it over, but you can still drive it, this way you can run your stock fuel system & pump, all you'll need is an intake/carb/dist., also, are you planning on running the surpentine pulleys? Heres a couple pix of mine.

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100_0959.jpg
 
Can tap the $2000 if NEED be. I figured I would so I could get electric fans. Are you at all familiar with the megasquirt system?
 
needsaresto said:
I must be lucky too.My mags arent cracked either.
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I'm sure there are some out there not cracked "yet", seeing this board covers the USA & all around, there are bound to be a + here & there on these heads, but 95% of them are cracked after 120xxx miles. Your in the 5% croud along with the other guy.
 
JoeDust, where've you heard about that problem with the magnum heads? This is the first I've heard about it... then again I'm not that knowledgeable about them
 
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