Hemi VS Magnum
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Professional
Joined: Dec 2021
Posts: 221
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From: Florida
You could go with an aftermarket intake and holley efi setup, that might give you some hands on tunability - rather than working with someone who is over writing fuel settings in your stock computer. When I was considering modifying the 5.9 magnum in my 2000 3/4 ton, I went through the options for my intended usage and came to the conclusion that factory was really hard to beat - I'd just be wasting my money and time. The 5.9 is a solid engine, probably one of the most durable engines Mopar ever built.... they had that engine since the early 70s and kept making improvements.. I think the only real issue was the magnum head crack problem, but that was solved by the aftermarket.
Champion
Joined: Sep 2012
Posts: 4,868
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From: Central VA
As mentioned, the 5.9 magnum motor is hard to beat. They make a lot of torque in stock form. A great place to improve the motor is with the cylinder heads. The stock heads are prone to cracking over time. I luckily found a brand new pair of Edelbrock aluminum magnum heads that I'm planning to install onto a rebuilt short block, along with a mild camshaft and the most compression I can run while staying with regular fuel. I also picked up a used M1 2 barrel intake several years ago and may also use the intake with the new build, since the 4.10 gears should help make up for the slight loss in low end when using the M1 intake. My transmission was recently rebuilt and properly beefed up, so it should hold up to whatever I throw at it. I just use the truck for towing and hauling, but want to be able to keep up with most vehicles on the highway. Just wish I could find a way to keep the 5.9 out of fuel stations, however, its hard to have your cake and eat it too...
Grand Champion
Joined: Aug 2009
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From: MAINE
My opinion stick with the magnum…..I work in a shop and I’ve done tons of hemi engine swaps/ rebuilds because they blow, like broken valves, wiped camshafts, head gaskets, broken pistons, basically a lot of problems…..I’ve dealt with many bad hemis…
the magnum is a stout engine….my 95 had 245k when I traded, and I beat the hell out of it off roading, never left me stranded….my current 5.9, with 165k, had a lifter tick cuz I didn’t know I had a hole in timing cover and lost to much oil (which has all been fixed) and still runs like a top, and in my 15 years working on vehicles I never had a blown magnum to deal with
the magnum is a stout engine….my 95 had 245k when I traded, and I beat the hell out of it off roading, never left me stranded….my current 5.9, with 165k, had a lifter tick cuz I didn’t know I had a hole in timing cover and lost to much oil (which has all been fixed) and still runs like a top, and in my 15 years working on vehicles I never had a blown magnum to deal with
Administrator
Joined: Apr 2010
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From: Clayton MI
Looking at JUST the engine, you get more power per dollar from the hemi. But, then you spend yet more money adapting the engine to your truck. That is complicated by the fact that pretty much EVERYTHING in your dash is controlled by a computer. None of the gauges get a direct reading from their related sensor, it all goes thru the PCM, and the PCM tells the cluster what it should be doing..... Which strikes me as a good reason to stick with the 5.9. 
(your truck IS 98+ isn't it?? I seem to remember reading that somewhere. If it's 97 or older, this becomes a non-issue.)
Long runners are indeed good for low-end power. Have a look at the kegger manifold that cam stock on the magnum motors..... Of course, those long runners are also why the engine pretty much runs out of breath around 4000-4500 RPM too.
Hughes and M1 are just about the only choices for a bolt-on intake. They stopped making these motors just about 20 years ago, so, aftermarket support on the performance side is pretty much drying up. You can still find the M1 on the used market.... but, they are pricey. At this point, likely more than the Hughes manifold.... The hughes manifold will indeed cost your some bottom end, on a completely stock motor. Feed it a decent cam, a good exhaust, bored out throttle body, and you can gain all of that, and more, back.
As for tuning.... Just depends on where you want to spend your money. There are folks that will write you custom tunes, last I checked, that was in the neighborhood of 600 bucks. On the other hand, for a bit less money.... You can buy the HP Tuners software, (single vehicle license) and tweak your tunes to your hearts content. Learning curve there is pretty steep though. Dyno tune is likely the *best* option, but, not inexpensive, and you won't find anyone to do it in some areas. (I live about 80 miles from Detroit, so, everyone and their cousin does dyno tuning there. )
(your truck IS 98+ isn't it?? I seem to remember reading that somewhere. If it's 97 or older, this becomes a non-issue.)Long runners are indeed good for low-end power. Have a look at the kegger manifold that cam stock on the magnum motors..... Of course, those long runners are also why the engine pretty much runs out of breath around 4000-4500 RPM too.
Hughes and M1 are just about the only choices for a bolt-on intake. They stopped making these motors just about 20 years ago, so, aftermarket support on the performance side is pretty much drying up. You can still find the M1 on the used market.... but, they are pricey. At this point, likely more than the Hughes manifold.... The hughes manifold will indeed cost your some bottom end, on a completely stock motor. Feed it a decent cam, a good exhaust, bored out throttle body, and you can gain all of that, and more, back.
As for tuning.... Just depends on where you want to spend your money. There are folks that will write you custom tunes, last I checked, that was in the neighborhood of 600 bucks. On the other hand, for a bit less money.... You can buy the HP Tuners software, (single vehicle license) and tweak your tunes to your hearts content. Learning curve there is pretty steep though.
Dyno tune is likely the *best* option, but, not inexpensive, and you won't find anyone to do it in some areas. (I live about 80 miles from Detroit, so, everyone and their cousin does dyno tuning there. )
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Professional
Joined: Dec 2021
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From: Florida
It’s funny you say that about 4K-4500, because my truck with the 5.2 pulls really hard after 3K but is gutless lower than that which is why I think it’s on its way out. My truck is a 99 and I heard about those complications with converting. My concern about keeping the stock manifold is that I want to convert to a 4150 throttle body so I can adapt to an LS dbw throttle.
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Joined: Apr 2010
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From: Clayton MI
It’s funny you say that about 4K-4500, because my truck with the 5.2 pulls really hard after 3K but is gutless lower than that which is why I think it’s on its way out. My truck is a 99 and I heard about those complications with converting. My concern about keeping the stock manifold is that I want to convert to a 4150 throttle body so I can adapt to an LS dbw throttle.
Also, the whole 'lightswitch' thing at 3K is symptom of a blown plenum.
My 96 was like that too.... rather lethargic below about 3K, but, once it goes over? Hang on TIGHT. Also, one of THE BEST things I did for performance on my high mileage 5.9 (180K) was replacing the timing set. That made a major difference in how the engine ran.
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Professional
Joined: Dec 2021
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From: Florida
The 5.2 isn't pulling as much air, so, it will actually pull higher into the RPM band.
Also, the whole 'lightswitch' thing at 3K is symptom of a blown plenum. My 96 was like that too.... rather lethargic below about 3K, but, once it goes over? Hang on TIGHT.
Also, one of THE BEST things I did for performance on my high mileage 5.9 (180K) was replacing the timing set. That made a major difference in how the engine ran.
Also, the whole 'lightswitch' thing at 3K is symptom of a blown plenum.
My 96 was like that too.... rather lethargic below about 3K, but, once it goes over? Hang on TIGHT. Also, one of THE BEST things I did for performance on my high mileage 5.9 (180K) was replacing the timing set. That made a major difference in how the engine ran.
Legend
Joined: Nov 2014
Posts: 8,098
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My take....worth exactly what you paid for it.....virtually everyone I've ever known with strokers (with the exception of Chevy 383s) has had a host of issues. Idle, throttle response etc and overheating is a big one.
Rather than trying to make something it's not you'd be ahead to just do a crate motor or a "stock" swap from an existing platform. The idea of a blower sounds cool. The idea of a stroker sounds cool. In reality you'd likely make more power and actually spend less with a crate motor....Hellcat, Ford 7.3 gasser, GM 6.0 LS, even a twin turbo Ecoboost.....
Rather than trying to make something it's not you'd be ahead to just do a crate motor or a "stock" swap from an existing platform. The idea of a blower sounds cool. The idea of a stroker sounds cool. In reality you'd likely make more power and actually spend less with a crate motor....Hellcat, Ford 7.3 gasser, GM 6.0 LS, even a twin turbo Ecoboost.....
As for the intake I ran the Hughes intake with their aggressive cam that came with a tune, ported throttle body (their "Big Gulp") and an swapping to 5 something gears maybe 6 something with air lockers and trusted axles to safely turn my 42s. It was gutless for torque down low but above 3k it took off. I then send my intake to Marty to die his magic which includes his VRP plates and divider (welded) along with the thicker aluminum plenum plate welded to the kegger. I like the modified kegger better then the airgap when I ran it. Just pulls so strong down low. Now I went with a Hemi swap because to get a 408 with down low torque and high hp (500 at the crank) I was at $10,000 just for the parts, not including boring or the motor which my shop said is about $100 per .10 over. Now that $10K was for forged parts to handle boost from twin turbos and I just decided to Hemi swap it.
Tell me, if you want, what tire size do you want to run and what type of offroad? We taking mud trails, rock crawling, or a little but of everything. Depending on your answers and your location I can get you parts at cost but they have to be shipped to my shop.