Some Discoveries
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Some Discoveries
I reviewed the VIN and discovered that I do NOT have the original 351 in my 81. VIN code is for a Windsor, but I'm seeing Modified/Clevland heads and fuel pump. Is there any easy way to tell what C6 id behind it (SB/BB) and has anyone done a Cleveland swap into an early 80's PU? Trying to double check everything before I start doing upgrades and rebuilds. Planning on taking care of the turn signal issues and brake issues (hopefully) this weekend.
~Critter
~Critter
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Ford used the same letter, "G" IIRC, to denote an M in 80/81 and a W in 82 and on. And 81 was the last year for the M, of which I have two, both with M's. And I've owned two 82's, both with W's. All had the same code for the engine.
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I reviewed the VIN and discovered that I do NOT have the original 351 in my 81. VIN code is for a Windsor, but I'm seeing Modified/Clevland heads and fuel pump. Is there any easy way to tell what C6 id behind it (SB/BB) and has anyone done a Cleveland swap into an early 80's PU? Trying to double check everything before I start doing upgrades and rebuilds. Planning on taking care of the turn signal issues and brake issues (hopefully) this weekend.
~Critter
~Critter
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While I agree fully with Dave about the 400, and in fact that's exactly what I'm doing, a properly built 351M gives excellent power. At one point I had two of the M's in two 1981 trucks. Dad's truck came with the M and never, ever had reasonable power. And, it got 10.5 MPG on the highway, in town, everywhere. Rusty's M has been warmed up with an RV cam and Edelbrock intake and 4bbl carb, and would run circles around Dad's and get 14 MPG doing it. So I really like M's and think you will if you either rebuild yours or go for a 400.
And, by the way, the difference between the two is scant - the 400 crank has 1/2" longer stroke and the piston pins are set 1/2" lower to compensate. The heads, intake, rods, pan, valve covers, and everything else are identical. So do like I'm going to do - call it a stroked 351M.
And, by the way, the difference between the two is scant - the 400 crank has 1/2" longer stroke and the piston pins are set 1/2" lower to compensate. The heads, intake, rods, pan, valve covers, and everything else are identical. So do like I'm going to do - call it a stroked 351M.
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Plans are on a 400 build, but using the block already in there. The data I have from LMC on decoding VINs said a different letter for the 351M. Also doing an emissions delete, since most of them are already gone. Also planning a 6-spd manual trans. Going to have to junkyard a lot of the cab parts. I was hoping that there was an easy way to verify if it's a 351 or 400. But I have to do the rear main anyway, so I'll check the crank then.
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Go see Dad's Engine thread for a discussion on the cranks. But if your engine will turn over pull the plugs and stick a straw in one cylinder and measure the stroke.
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If you do have a 6 speed that will fit the engine be careful, you will probably need the transfer case also. I know on the diesel six speeds they have a different output shaft so they need the transfer case that goes with them. And none of this has a place for a mechanical speedo so there is no place to hook your speedo up.
They broke what they had going before. Any Ford transfer case will mate with any 4x4 Ford tranny, until they came out with the 6 speed.
They broke what they had going before. Any Ford transfer case will mate with any 4x4 Ford tranny, until they came out with the 6 speed.
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If you do have a 6 speed that will fit the engine be careful, you will probably need the transfer case also. I know on the diesel six speeds they have a different output shaft so they need the transfer case that goes with them. And none of this has a place for a mechanical speedo so there is no place to hook your speedo up.
They broke what they had going before. Any Ford transfer case will mate with any 4x4 Ford tranny, until they came out with the 6 speed.
They broke what they had going before. Any Ford transfer case will mate with any 4x4 Ford tranny, until they came out with the 6 speed.