Something I just Need to Talk About

Sorry, this is not strictly A-Body related but this is where I post so some of you already know me a little. When my brother died last year he left seven non-running cars on his tiny property. I have managed to resurrect four of them so far and now I am digging into the fifth, a 1962 Chrysler 300. It's the non-letter Sport model. It originally had the 413 with the in-line dual-quad arrangement but now I believe it has a RB 426 wedge engine. It has the dual-point, mech tach drive, and the block ID pad next to the distributor has a "42" and a "HP" on it. I have not yet pulled a valve cover to see if it has mechanical adjusters. It currently has a Wieand dual quad manifold and the exhaust manifolds look like they're from an earlier 413 with the cross ram (they have the attachments for the heat stoves under the plenums).
View attachment 171557273220200731_115039 by Jim Harris, on Flickr
View attachment 171557273320200731_115054 by Jim Harris, on Flickr
So my only question at this point, what is the significance of the "HP"?

PS - I am also selling his NOS SR1 Viper replacement engine currently. All proceeds are going to my niece to refurb the house.
View attachment 171557273420200702_104643 by Jim Harris, on Flickr

Great for helping out the family for sure.

Not usually a fan of pre- 63 mopar anything but that thing is cool and sleek lookin as hell.
Keep us up to date. Love to see more of that beast.....lol.

Dave