looking at the numbers on the motor that I got out of a 81 D150

head part number 4104362, so that is a 79-80 mechanical lifter head
block casting number is 2806830-7, that makes it a 68-75 RG block

the serial number stamped on the pad behind the alternator has

4225 T 312

I'm confident the 225 means it is a 255
what about the 4,, would that mean 1974?
any idea on the T
is the 312,,, March 12th?

thanks

T is for truck?

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50 chrysler,54 Plymouth, 64 Valiant conv 4 speed, 66 Valiant V8 wagon, 70 Challenger R/T 440+6 conv 4 speed,80 Colt, 98 Neon ACR,84 Honda V45 Magna
Taking care of 57 300C conv,48 T&C conv. Missing my 67 GTX and 36 Ply coupe

T= Trenton Plant

_________________
Scrapple: Because a mind is a terrible thing to waste.
73 Duster - Race Car
66 Dart Wagon - DD
178" FED
82 D150
All Slant powered

found the magic decoder info at this site
http://www.yearone.com/updatedsinglepag ... bers3.html

from this it does appear the the
4 does indicate 1974
225 certainly is 225

the text indicates that the T for truck is after the year and before the displacement, at least on the V B/RB blocks,
so perhaps this is a Trenton engine,,