motor number gurus 3.oL SC
 

in doing some research here I ran across some of grady's old posts on engine numbers and have a question maybe someone can clear up. in the example posted the 80 SC motor number was as follows 6401025

as described the 6= 6 cylinder, 4= engine type (more on this later), 0 = an 1980 3.ol & the last four the sequential motor serial number.

so, does the "4" engine type reference the higher compression, smaller heads & O2 sensor of the 80-83 models?

I ask this because looking over the cert of authenticity from my old 78 3.oL ive found the following number ID, 6580083. as I decode this I find the 6 cylinder motor, but the motor type, 5 has me wondering does this designate the 78-78 3.oL motor with air pump & the bigger heads? additional info, this was a California car so maybe the 5 has something to do with that? ive noticed in my research that the 74-77 middies have a specific CA specific motor designation numbers. did the 3.oL power plants have the same differing designation for CA models? also, as I understand it by 1980 all the SC had the 50 state designation. any truth to this?

per the rest of my old 78's numbering makes perfect sense, the 8= a 78 and the sequential number of the 83 3.oL produced. fun fact, my older 78 had the vin number of 9118200049, meaning the 911 model, 82 designating a coupe, and the sequential being the 49th SC coupe produced. I really should not have cut up & caged it to go racing in such a car with 80k miles,,, eh?

I ask because I'm going to look at a transplanted 3.oL car tomorrow that the guy has no idea as the year of the motor is.

any help would be great, it's times like these I really miss not being able to email grady directly... RIP sir!

t

great share. I actually registered my old 78 at the site some years ago. last I looked it was the 2nd oldest SC registered there.

that chart also confirm my assumption that the "5" motor designation is for the 78-79 big head version & the "4" is for the 80-83 02 sensor, higher compression models that closed out the 3.oL run...

t