gtuplin

This must be the most confusing thing ever! Where they all on drugs in the factory when they built these things?
I read and read and find so many conflicting arguments regarding the casting numbers on these Cleveland blocks that I am clearly uncertain who to put faith in!
Seems like a simple request, just need info but you dive into it and nothing makes any sense at all!
I will make it short, I have a "M" code 71 convertible XR7, been parked for 19 years and has 60K I have service records but honestly cant be sure if they are complete but no reason to doubt them. Had small items done at the dealer when new ect but nothing serious as with the rest of its mobile life. I will be restoring the car, engine is stock and have pulled it to see what it needs but the cast number on the block is D0AE- there is no letter following it and the production date is Dec. 5th 1970. it has the 4* closed chamber heads and does have 4 bolt mains. I read on many sites that this casting number was also used as Boss block, but find it hard to believe a 71 cougar would end up with a BOSS block! So what do I have?

CJR09

yeh all the codes I have - have a letter after the DOAE-, as in I think from the information I have there is no code of just DOAE-, that isn't to say my information isn't lacking.

From what I understand the '71 xr7 m code should have block casting code DOAE-L, which as you say is the same for the '71 351 Boss.

interesting that cast date is '70 year - maybe pre Boss - Boss?

are you sure it is the factory block - do you guys have any way of determining that it is correct block through vin/chassis stampings or sido's?

maybe an assembly line screw-up? where doae- casting maybe wasn't clear and mistakenly put in wrong chassis?

sorry cant be of greater help

gtuplin

The car manufacture date matches the block cast date by 3 months so would think we are safe to assume it is original and again no records of work done. Main cap has casting number DOAE D and all 5 caps are 4 bolt where I understand some later years only 4 were 4 bolt. Not sure I understand or believe that but did read it at one time.
It is a nice clean engine still STD so it will make a nice new beginning for a restoration.

mil1ion

Remember the 1971 models started to be built in August of 1970.

So a block/heads/manifolds date casting as early as of *0F20* is possible for a August built 1971 car.

Since O in 1970 stands for a Torino for which the 351C was initially designed for, your numbers match

mil1ion

Does this help any? It is from Tom Monroe's Book.