Mopar 360/320 Crate Specs

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EdM

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I received a box of documentation for my recently acquired 70 Dart Swinger (my first Mopar). There is a Summit receipt for a Mopar Performance Magnum 320 (P4510852). I have done a pile of searching and, surprisingly, find little about the motor. Can someone please provide info such a cam specs (Hyd roller?), head quailty/valve size, CR, rod and crank info, etc. It has TTI headers, runs great, pulls pretty well. Great street motor it seems. TIA.
 
I found this from an archive section of another forum, looks like it was copied from some other source like a web, or catalogue listing. I can't say how accurate it is, but may be useful.

Part # P4510852
360 MAGNUM CRATE ENGINE
320 HORSEPOWER
385 Ft. Lbs. Torque

Why take the time and expense to rebuild your old small block when you can bolt in a 320 horsepower Magnum engine for about the same cost? Dyno testing produced 320 Horsepower at 4750 rpm. Torque output is over 385 ft.-lbs. at 4000 rpm. Engine now comes standard with new Magnum R/T Big Valve Cylinder Heads. Mopar Performance recommends the use of a 750 cfm Holley Carburetor (P4349228- Available through BPE) and 1 5/8" Exhaust Headers.

Specifications:
* Built with all - new components
* New Magnum R/T Big Valve Cylinder Heads
* Distinctive Mopar Performance Cast Aluminum Valve Covers
* High-Strength Stainless Steel Valves - 2.02" Intake and 1.62" Exhaust
* Heavy-Duty Valve Springs
* Hydraulic Roller Camshaft - 250°/264° duration, 0.385"/0.401" Lift
* Dual-Plane, M1 4-bbl Aluminum Intake Manifold
* High Volume Oil Pump
* Mopar Performance Electronic Ignition Kit with Distributor
* Does not include accessory brackets (Sold Only Here At BPE)
* Not Recommended For Factory MPI Installations
 
DrEamer said:
I found this from an archive section of another forum, looks like it was copied from some other source like a web, or catalogue listing. I can't say how accurate it is, but may be useful.

Part # P4510852
360 MAGNUM CRATE ENGINE
320 HORSEPOWER
385 Ft. Lbs. Torque

Why take the time and expense to rebuild your old small block when you can bolt in a 320 horsepower Magnum engine for about the same cost? Dyno testing produced 320 Horsepower at 4750 rpm. Torque output is over 385 ft.-lbs. at 4000 rpm. Engine now comes standard with new Magnum R/T Big Valve Cylinder Heads. Mopar Performance recommends the use of a 750 cfm Holley Carburetor (P4349228- Available through BPE) and 1 5/8" Exhaust Headers.

Specifications:
* Built with all - new components
* New Magnum R/T Big Valve Cylinder Heads
* Distinctive Mopar Performance Cast Aluminum Valve Covers
* High-Strength Stainless Steel Valves - 2.02" Intake and 1.62" Exhaust
* Heavy-Duty Valve Springs
* Hydraulic Roller Camshaft - 250°/264° duration, 0.385"/0.401" Lift
* Dual-Plane, M1 4-bbl Aluminum Intake Manifold
* High Volume Oil Pump
* Mopar Performance Electronic Ignition Kit with Distributor
* Does not include accessory brackets (Sold Only Here At BPE)
* Not Recommended For Factory MPI Installations
Click to expand...

Great. Thanks a bunch.
 
2007 Mopar Performance catalog

screenpic 5.jpg
 
Yeah, that's a really tame cam,not much different than a stock 2bbl. Should make pretty good fuel mileage.
I think the C/R was 9.1:1 with iron Magnum heads.
I've seen the dyno graph published with that engine; the power plateau is almost dead-flat from 4250 to 5250, with a torque peak similarly flat from 3500 to 4000. Very nice for a streeter.

Those Swingers were pretty lightweight; Mine with a 340/A833 came in at 3330 with me in it, back in 71. I mightabin 135 soaking wet, making the car a tic under 3200.
The biggest problem with that body is getting decent tires under it. After I learned to drive with the E70-14s,I really really liked that car. But with the power on,she was a handful in anything but a straight line. Later on with G60s and 4.10s things were a lil better,lol.
That 360/320 only needs 3.91/4.10s and an A518 to give your Ford a bit of a workout, while still keeping the fuel economy.:) Heck, that 320hp could/should get her into the 12s at over 106mph. And 385ft lbs with 3.91/4.10s and an A518 would be a killer street combo, if you can figure out how to keep her from frying the skinny tires.

Congrats on a fine acquisition.
 
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