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I know a guy who wants to sell his project truck, its a 77, supposedly complete for $1000 bucks. But what i need advice on is the 400M engine. He has a 400M engine and C-6 Tranny both professionally rebuilt, still wrapped in plastic (I know the shop and its legit) that I need for my truck. I need a new engine and tranny. HOWEVER i have heard mostly poor things about the 400M, someone even referred to it as a misplaced anchor.... so my question is, how bad is this engine? Will the HP drop be insane? This is a steal for the parts i need but will i regret it later having this engine? Im looking at it in the morning so any quick advice is appreciated. Thanks
Oh p.s. I currently have a 460 and 4 speed in case you havent seen my truck.
If it is built to stock '77 specs, it's at about 149 hp, give or take.
If it is built with straight up cam timing, a better cam, & some compression, then some head work or new heads, a manifold, headers, and the usual hot rod stuff can get it into 300 or even 400+ territory.
So I would find out what spec it's built to. My guess is stock 7something CR and a retarded, roundish cam....
BTW, it's just "400". The 351M, derived from the 400, is the only "M". Some think it means "Modified". Matters not, as that is even weaker than the 400, and the only "fix" is to make a 351M into a 400, and add the other items previously mentioned.
You could just buy his transmission and get another 460 if you don't like the 400. In stock form they are thirsty and gutless, ask to see some receipts and see how it was built they can perform as mentioned above and really they weren't any more gutless than the 460s of the same era.
-Johnboy
68, Most of us here don't care for the 400, they are alright engines, gas hogs, etc. But one can be rebuilt to be respectful, I know guys that run them and are happy. It isn't a FE or a 460 but, new rebuild engine and C6 tranny + truck for $1000.00 is something that I would consider, (if I had the jingle) and think you should too. IMHO
my dad has a 400 4spd in his 79 F-350 and it has pulled over 10,000lbs with no problem. It is not fast of the line but it is great for a truck motor. He has had it for 11 years and has only done small stuff to it
Well i went to look at it and i have mixed feelings. The engine is in fact a 351M, something redone to it to make it a 400. (According to this guy) Idk , he didnt really know what he had, was his brothers truck. But it was professionally rebuilt 3 yrs ago, and is still in the package. The C-6 was rebuilt under the table by a friend who works at a tranny shop. However, the metal all looked really good its even stripped and primed, has new lift kit in the box, engine stand, paint, paint gun, and all the other parts for the 77 for $1000. Seems like a good deal to me.
I have mixed feelings though where that will leave me. Ill have a 77 in parts, a 68 with a broken 460 and an emptier wallet. Not sure what the best strategy is... Im not sure if ill be happier with the 68 or 77 in the long run or how to get either of them to a happy vroom vroom stage oO
Back to your engine. If you can't find out how it was built, it's a crap shoot. BUT, USUALLY, if someone goes to the trouble of upgrading to 400 cubes on a 351M, they USUALLY, MANY TIMES, MIGHT HAVE, SHOULD HAVE, upgraded at least the cam timing, MAYBE the compression. Can you contact the shop that did the work? If you have the guys name and the approximate date, maybe a tag off the motor....who knows, maybe they have a copy of what they did.