Head Identification

[cuba_pete]

'72 commando with EFI intake manifold but with the Carter carb...okay...think it's from somewhere around '82...not for sure. Went to put new plugs in it, but Advance Auto gave me 13/16" plugs and they don't fit. I had 5/8" plugs in it, but didn't check when I went to get the new ones.

Question: where are the casting numbers for the head, and where can I cross this to a year so I can get the correct plugs? All of Advance's numbers cross to 13/16" (Champion p/n 405) plugs--except around '82 5/8" (Champion p/n 84), lucky guess.

Easily visible on the head is the number 84 stamped on the horizontal area between #1 intake and #1 exhaust ports.

The block has 409C05 stamped on the passenger side between #2 and #3 cylinders.

Is this even a 258, as the valve cover suggests, or does that head fit on the 232 also?

The intake manifold has EF3237858 stamped on it by #3 intake port. Where can I cross that?

Any assistance appreciated.

 

[SteelHeadz]

Sounds like a Heinz57. I suggest that you take 1 of the old plug to Advance and have it matched. Hard to tell on the cylinder head for identification. It's usually identified by looking at the valve size, intake and exaust port shape and size, at least that's how i I.D. them.

 

[cuba_pete]

Yeah...I kind of got that....unfortunately, I swapped out the plugs when I got it, and put in those pulstar plugs, p/n BE1, which fit a crapload of applications. They actually are just short of the .750" reach, but did have the 5/8" shell. They didn't seem to have any effect whatsoever, and are running rich, even though the carter is leaned out as far as I can get it, and timing is fine. It has several odo-rollovers so I was trying to find a hotter plug for it to compensate. But, if I didn't have the proper plug when I bought it, I don't want to put in a plug with too high of a reach and slam the pistons. I am not sure how close they are, since I haven't had the head off. I don't want to mod it, I just wanted a slightly hotter plug. I think id'ing the head is my best bet.

 

[54cj3b]

kinda sounds like the engine from a old rambler or hornet 13/16 was common in the rambler the one I had about 25 years ago hade them it was a 68 or 69 cant remember so long ago