Engine is stock 94 5.2 magnum. Would there be a power gain swapping from the stock throttle body/barrel style intake manifold to an air gap style intake with carb? Thanks in advance.

Check out Hughes engines they have been doing some magnum stuff

Above 3700 rpm the Mopar Performance MPI intake has shown horsepower gains

http://www.steigerperformance.com/docs/MPIIntakeManifoldInstallationGuide.pdf

Long discontinued, so it's Ebay or similar.

As stated above the old Mopar M1 intake was good if you can find it. My old 5.9 R/T ran in the mid 13's with that intake and other bolt-ons.

The long tuned length runners on the OEM magnum intake are optimized for cruising speed so you might lose a bit of bottom end/low speed efficiency. My memory is hazy but I think they were setup for peak efficency at 1800rpm. I think anything above 3000rpm you will begin to see gains with an aftermarket intake. I know mopar performance made several ECU options of the OBD-1 system in your 1994 but I don't recall if any of them were calibrated for the mopar high rise magnum intake.

Best bang for the buck is a cam swap. I put the baby Hughes Roller in my 5.9. Night and day difference.

Check out www.utawesomeperformance.com

The stock “beer barrel” intake runners are 15.5 inches long at the centerline of the runner. There is another 3 inches in the cylinder head for a total of 18.5 inches. This length tunes to resonance between 3200 and 3800 rpm. That matches the 5.2 but is not optimum for the 5.9 V8.

The 8L V10 has a 25 inch runner length and double resonates, first at 1750 rpm and then at 3200-3600 rpm.

The longest path of the variable 5.7 Hemi is about 27 inches.

Cutting back the beer barrel runners like the excellent pictures at utaperformance show will boost higher rpm torque and hp.

Me personally I thought about lengthening the beer barrel runners by adding 4” of aluminum tubing to move the entrances to the opposite side of the plenum, but the new 22.5 inch length would not move the resonance to the 1500 to 1800 rpm cruise range for better hill climbing.

I wish a V10 style manifold had been made for the 5.9 V8.

Here’s a M1 intake for sale.

https://www.facebook.com/groups/716...980529075/?sale_post_id=3595265980529075

Cut two runners off.

What would be the short path length of the 5.7?

From your description, it almost appears to Me that the Magnum intake is the best compromise for idle to 5000rpm?

sample quote

Chrysler installed the “active intake manifold” that varied the length of the intake runner “to expand the engine’s torque and horsepower range” on some, but not all, applications. When it’s activated, the butterflies in the intake runners open up at 4,000 RPM to create an intake path that’s half as long, so the engine makes an additional 25 horsepower without losing any torque and ends up with 390 horsepower. You can actually feel the difference when the short runner valve switches over in my pickup truck.

end quote

from
https://www.knowyourparts.com/technical-resources/engine/57l-hemi-anatomy/

It is possible that cutting a second entrance in the bottom of the intake runners of the beer barrel Magnum intake manifold would create an improved performing manifold where the airflow “would decide for itself which opening to enter” based on rpm. Ford discovered something like this on an intake that originally designed with a mechanical valve to vary runner length. Ford engineers discovered the airflow “naturally” chose the correct entrance. I cannot tell you the shape of that new entrance: maybe round hole, maybe centered rectangular slot, maybe offset long slot on the side that enhances swirl.

The beer barrel Magnum intake was designed for the Magnum 5.2 and suits it pretty good.

I speculate that the 5.9 V8 needs runners that are greater in cross sectional area, and double resonate, ideally at 1700 and 4100 rpm.

I thought the 0.69 overdrive of a 46RH is right for a 5.2 Magnum,
but a 5.9 V8 needs a .62 overdrive
and a 8L V10 needs a .50 overdrive

To the original poster instead of small mods to a Magnum 5.2
he should consider transplanting in a 5.7 Hemi.
Way greater bang for the somewhat bigger bucks.

The guy came here inquiring about a $200 intake swap and is getting recommended $6k motor swap instead?

To the original poster: we need more information. Is this motor being swapped into something else, or is it in the original vehicle? That beer barrel intake is designed to operate off idle to probably 5,000RPM. An Edelbrock Air-gap or similar operates at 1500-6500RPM. You would probably see a peak gain while also losing down low without matching other parts. Need to know what chassis the motor is in, intended usage, rear gear, etc to give a proper answer.

Would it really cost $6000 to transplant a 5.7 Hemi into a 94-95 Ram?
I have been considering it using used parts and ballpark $2500 seemed possible.

Chrysler’s original press release claimed the 5.7 Hemi was 6% more fuel efficient too.

Is my fuzzy memory wrong that a few years ago Sergio publicly stated a $6500 new parts kit would be offered to put “clean emissions” 5.7 Hemi transplants into vintage automobiles?

Didn’t Tom LaSorta brag a few years ago that what was truly great about the Hemi 5.7 was that Chrysler was building it at Satillo Mx at an internal cost of $850 each.

The 2-barrel M1 intake listed above is being offered at $550.

I do agree that the runners of the beer barrel intake manifold could be cut shorter for ballpark $200.