[DAVID GAGNARD]

Tom;

Just my opinion for what it's worth.........

The 351-M is based on the CLeveland style heads,but they are not as good as the original Cleveland heads,maybe with a lot of money and work they could be as good..........

Most consider the block as a "big block" vs. a small block enigne even though it is a small block displacement.........

I have had a vehicle with this same motor and have driven quite a few over the years,my opinion is they are a big, fat, heavy, lazy engine and it takes way too much money to make them "run".........maybe that's why it was given to you.....around here you can get them running out of junkyards for as little as 50 bucks if you pull it.............

better off with a 351-W,more performance parts avaliable and they are still fairly plentiful in the salvage yards........

depending on what you want to install it in, it may or may not fit, as it is physically bigger than the 351-W motor and also heavier............

I know 3 or 4 guys that replaced running 351/400M's with 351-W's and actually could not give away the running M motors,they had to haul them to the scrap dealer to get rid of them..........

Just my .02 cents............

David