Is there a 400 'HP' engine?

[Challenger_7]

Hi all

Today, I was shown a 400 block which the chap owning it said it was an "HP" engine.
Upon asking him how is that, he showed me the HP stamp on the corner of the engine, see photo attached.
You can also see a funny shaped cross next to it as well as some sort of chinese looking mark.

Does anyone recognize this, and is there an HP 400 block?

Cheers

[John_Kunkel]

There was a HP 400, it used the same cam and exhaust manifolds as the HP 440 of an equivalent year.

[Challenger_7]

Hi John, and thanks for the input.

I would be interested in seeing a photo of the same section of the engine of an HP engine. Somehow I am not quite convinced that this is genuine. The letters of the HP are of different size to the rest of the lettering, and whats with the cross??

Farouk

[Nacho-RT74]

MAGNUM is HP

[John_Kunkel]

The pad stamping looks like most I've seen, the Maltese cross means it left the plant with .001" undersized crankshaft bearings.

Here's how it decodes:

4= 1974
T= Built at the Trenton engine plant
400= Displacement
11 15= Build date November 15, 1973

Can't make out the Chinese character, could be a crossed out misstamp or a casting flaw.

[73chgrSE]

Would they still have had the same horsepower/torqe?

[71butterbee]

Yeah its a HP block. I have a 73 ralley charger with a 400 HP and the stampings you have look just like mine. Im sure at least the block is HP!

[Challenger_7]

Thank you all for your input, so educative

Ok, just to add to my education, what makes an HP block HP. Is it the componenets, i.e. forged crank and maybe special pistons, valves etc or is the block actually structured differently.

Would appreciate some details.

Thanks, Farouk

[Nacho-RT74]

Magnum ( HP ) engines:
Double spring valves ( at least mine from factory ).
HP exhaust manifold.
4 Bbls intakes ( spreadbore in 400 case )
windage tray.
"HP" camshaft, except as far I know on 74.


Steel crank untill 71, however some 72 have them and I have known some 73 with 4 speeds

[Charger1973]

Heres mine.  Its in my 73 but its a 74 HP motor

[69CoronetRT]

...what makes an HP block HP. Is it the componenets, i.e. forged crank and maybe special pistons, valves etc or is the block actually structured differently.

There is no difference in an HP verses non HP block but there are some differences in the components.

[K9COP]

I've just been gifted a 3rd gen with "magnum400" callouts on the hood...

[Charger1973]

I've just been gifted a 3rd gen with "magnum400" callouts on the hood...

You can gift it to me if you dont want it   

[K9COP]

Now come on, we spoke about this car already. If you think it's worth shipping from Grand Cayman, talk to me. However, I never really knew what the 3rd gens looked like till I found this one, and the two cars in your signature look so cool, I may keep it and restore it after I finish my 68. I'd like to do something rad to it..

[Charger1973]

Im just kidding, I think you should fix it up.  They make awesome drivers and theres alot you can do with them. 

[Challenger_7]

Thanks guys for all your input and taking the time to comment, much learned here again And thanks Charger 73 for making the effort to post the pic.

Its just I have seen "383 magnum" and "440 magnum" hood name plates but had never seen a 400 magnum.
I just logged onto "yearone" and discovered they have the 400 magnum nameplates in stock.

Cheers

[K9COP]

Here you go, if you like you can buy the Charger it's attached to..