i have what i believe an M-21 but i can't figure it out for sure. the tranny has my VIN the side but the code next to it doesn't jive with code books! anyone have info on whynot? and my 396 has had it's code ground off during a rebuid in the 80's. is there any other way to verify numbers? from everything else i have found on my 69 SS, it looks to be a 350hp/M-21/3.55:1 car.

i have what i believe an M-21 but i can't figure it out for sure. the tranny has my VIN the side but the code next to it doesn't jive with code books! anyone have info on whynot? and my 396 has had it's code ground off during a rebuid in the 80's. is there any other way to verify numbers? from everything else i have found on my 69 SS, it looks to be a 350hp/M-21/3.55:1 car.What is the code next to your CON VIN on the transmission? All 69-74 Muncies got a letter designator at the end of the tranmssion date code, A=M20, B=M21 & C=M22. Are you sure the CON VIN on the engine was ground off? KC & Atlanta stamped the CON VIN on the rough cast area by the oil filter. See http://www.chevellestuff.com/69velle/images/v8engine_stamp_location.jpg. If it's not a KC or Atlanta car the data are gone forever. A casting date on the block compared to the body date would at least confirm the engine was built before the car.

dale, thanks so much. but where is the tranny date stamp located? near the part of the VIN? and what does "CON" mean? and i will check the engine for a code near the oil filter. and i do have a kansas car. and does the engine have a date stamp or do i have to use the casting number? the engine code i'm looking for is on the protruding iron by the water pump on the ride side of the car. that's gone, it's just smooth now.

dale, thanks so much. but where is the tranny date stamp located? near the part of the VIN? and what does "CON" mean? and i will check the engine for a code near the oil filter. and i do have a kansas car. and does the engine have a date stamp or do i have to use the casting number? the engine code i'm looking for is on the protruding iron by the water pump on the ride side of the car. that's gone, it's just smooth now.Sorry about the abbr., CON is short for "Confidential" or "Concealed", although it's not really 'concealed' in many cases. The CON VIN on the engine won't have a date stamp but rather it'll be like the one on the transmission, i.e., 19K3xxxxxx, and may be difficult to read due to the location.

Transmission date stamping could be on any flat surface (like the flange where it bolts to the bellhousing or where the tailshaft bolts to the main case) but normally near the CON VIN. Format of the date code is something like P9C01B for Muncie (P), 9 (1969), C (March), 01 day and B for M21. Month letters used are on this page: http://www.chevellestuff.com/generic/muncie.htm

The engine pad that you indicate is blank is where Tonawanda would have stamped their date and ID information so it that's smooth there's no way to know when the engine was assembled or what horsepower rating (325/350) or what transmission it was destined for. If you find the CON VIN stamped by the oil filter and if the sequence number portion doesn't begin with 3xxxxx then it could be an engine from a Camaro (5xxxxx) or passenger car (0xxxxx). The plant designator would be different as well but too many to list. Bottom line, IF the CON VIN is there and it's (1) not a 69 (with the number 9) or the letter K (for Kansas) then the rest doesn't matter, it's not original to the car. Here's a CON VIN engine stamping for a 69 KC SS Chevelle. http://www.chevellestuff.com/69velle/engines/vin_location.htm

Bottom line, better to see if it's there and report what you find than me confusing you with all the possibilities. :thumbsup:

thanks, i'll check it out tonight around 530 pm PST and write in. thanks