What makes a engine a magnum?

[Charlie71rt]

What makes a 1971 383 magnum different from any other 383

 

[beanhead]

Camshaft & some valvetrain parts, and compression ratio/piston height and type. I think that's it? Carburetor was different also, no 2bbls on magnums but that's technically not an 'engine part' so I don't know if it counts toward your question.

 

[PlymCrazy]

I was taught that the term “Magnum” is unique to Dodge high performance engines. Plymouth calls it a “Commando”.

 

[Ray70Chrg]

windage tray and possibly the left exhaust manifold. Not sure about a dual point distributor. 383 magnum engine had a HP stamped on it.

 

[dspur]

Not sure about 71, but in earlier years there were two versions of the 383. Mine is a 69. I'm sure there are some differences in internals, but there is only 5 hp difference. 330 hp and 335 hp. I have the 330 hp version and it has a four speed and factory air. I am sure Chrysler was disappointed that the hp differences were minimal

 

[Kern Dog]

The question is vague.
Ma Mopar put the "Magnum" name on several engines from the 60s/70s through the 3rd generation Hemi.
The classic 383 and 440 Magnum series always came with higher flow exhaust manifolds, different camshafts, windage trays, and 4 barrel carburetors. Then Ma Mopar revised the LA series engines from the 318 and 360 into the "Magnum" 5.2 and 5.9.

The printing is hard to read but this 2007 5.7 Hemi has "Magnum 5.7 V8" on the throttle body cover.

 

[Demonic]

I am sure Chrysler was disappointed that the hp differences were minimal

Probably not. Why would they be disappointed with something they designed ? That's the way they wanted it. The mind set of the time was sales. Even in the late 60's early 70's there was a considerable portion of the population that was resistant to high performance culture. Our parents and grandparents. Having both 383 and 440 4bbl engines AND 383, 440 Magnums, you can create a sales distinction. So a 440 in a C body or a 383 in an air conditioned Coronet appeals to a guy who wants to tow a boat and not go to the dragstrip.

 

[Kern Dog]

The ratings that they hung on their engines were not always accurate. Mopar Action magazine has printed articles where they felt that the published compression ratios and HP ratings were as much about deceptive marketing as anything else.
Anyone that has taken apart a stock engine and actually measured deck height, chamber volume and head gasket thicknesses can corroborate.
My '70 383 had a published C.R. spec of 8.7 to 1. The pistons were .076 in the hole, the chambers were almost 90 ccs. I think I calculated it at close to 8.12 to one with the stock .020 head gaskets and 7.85 to one with the common .039 Fel Pro gaskets.
The 440 4 barrel in C bodies was often rated at 350 HP, the Magnum was 375 because it had the hotter cam, the HiPo exhaust manifolds, windage tray and dual exhaust pipes.

 

[Ray70Chrg]

Not sure about 71, but in earlier years there were two versions of the 383. Mine is a 69. I'm sure there are some differences in internals, but there is only 5 hp difference. 330 hp and 335 hp. I have the 330 hp version and it has a four speed and factory air. I am sure Chrysler was disappointed that the hp differences were minimal

I believe there was 3 versions of the 383. You could choose a 383 with 2 bbl. carb and single exhaust. HP was 280 at its highest level.

 

[dspur]

I believe there was 3 versions of the 383. You could choose a 383 with 2 bbl. carb and single exhaust. HP was 280 at its highest level.

yes. 383 was used in a lot of vehicles including those big Chryslers.

 

[RemCharger]

What makes the Burlington coat factory better than other coat factories ?

 

[dspur]

Probably not. Why would they be disappointed with something they designed ? That's the way they wanted it. The mind set of the time was sales. Even in the late 60's early 70's there was a considerable portion of the population that was resistant to high performance culture. Our parents and grandparents. Having both 383 and 440 4bbl engines AND 383, 440 Magnums, you can create a sales distinction. So a 440 in a C body or a 383 in an air conditioned Coronet appeals to a guy who wants to tow a boat and not go to the dragstrip.

Understand. I had read that sometime back, can't remember exactly where, that they felt there would be more of a difference between the two. If I can find I will post a link

 

[kiwigtx]

A Magnum is only one quarter the size of a Methuselah if that helps at all.

 

[MoparLeo]

Cylinder heads, camshaft, intake and exhaust manifolds are the differences.
I stand corrected on the heads and intake.

Ultimate Chrysler 383 Mopar Engine Guide - Specs, Cars, & History

Guide to the Chrysler/Dodge/Plymouth 383 Mopar V8 engine used in Dodge Super Bee, Charger, Challenger, Plymouth Road Runner, 'Cuda, etc.

musclecarclub.com

"The High Performance and Truck Variants of the 383​

From 1968–1970, there was a high performance version of the 383 Magnum from Dodge and 383 Golden Commando from Plymouth. From 1968–1969, power output was 335 horsepower and 425 lb-ft of torque. The compression ratio was 10.0:1, and the exhaust valves were widened to 1.74” due to the new head. The carburetor was a four-barrel Carter AVS, which sat on top of a new dual-plane, high-rise intake manifold made from cast iron. In 1970, a four-barrel Holley unit replaced the Carter.

Part of what made the high output 383 so powerful was that it used parts from its larger Dodge 440 Magnum and Super Commando counterparts. This included the heads, intake manifold, camshaft, and exhaust manifold. Compression dropped from 10.0:1 to 9.5:1 in 1970, the last year the variant was available."

 

[3sloppydogs]

Not much but enough to differentiate
Example

 

[Kern Dog]

Cylinder heads, camshaft, intake and exhaust manifolds are the differences.

Sorry, man...the 383 and 440 all used the same heads and 4 barrel intakes on the Magnum engines as they did on the NON Magnum.
The C body 440 4 barrel intake was the same as what came on the 440 Magnums in the Challenger, Charger and Coronet R/T models.

 

[Demonic]

I believe the most prevalent answer would be:

Camshaft, valve springs, exhaust manifold, carb, air cleaner. Most everything got 906 heads at one point in the late 60's.

 

[JR_Charger]

Not sure about 71, but in earlier years there were two versions of the 383. Mine is a 69. I'm sure there are some differences in internals, but there is only 5 hp difference. 330 hp and 335 hp. I have the 330 hp version and it has a four speed and factory air. I am sure Chrysler was disappointed that the hp differences were minimal

What about torque?

 

[WileERobby]

One of the Monkees TV show.

 

[dspur]

What about torque?

Not sure. I’d guess a good bit less.