M318 or LM318?

[TonyJ1961]

I am in the process of closing a deal for a '73 Correct Craft Mustang equipped with a 318.

My question is: when was the M318 last used? Could this '73 have a M318 or might it have the LM318?

Any help would be appreciated. I know there are differences in the heads and rocker covers, but I have not seen the engine yet.

Thanks,

Tony

 

[Tahoerover]

73 would be a typical LA318. Are you asking about a POLY 318 vs a LA318?

 

[TonyJ1961]

I am familiar with the differences. The A318 is about 50 lbs heavier and uses a polyspherical cylinder head. The LA318 (or Light A) uses a wedge head design. Chrysler went to the LA design to save weight and it was cheaper to build.

 

[Tom_Witt]

Chrysler stopped production of the M318 with poly heads in 1966. The LM318 with hemi heads came right after. I found this out the hard way-my 1967 Tollycraft had Dec. 1966 M318's installed. Easiest way to tell is the M318 exhaust manifold ports are evenly spaced while the center two exhaust ports on the LM318's manifolds look like they share one outlet.

 

[Tahoerover]

LM uses a wedge head not a hemi head.

 

[Tom_Witt]

My mistake, thanks for the correction.