the truth
Freshman User
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the truth
i had a argument with a person today about the 400M. she said that it was a big block. now i have a 400m in one of my trucks and know from experiance that it is a small block. did ford make a 400m bigblock or is she just bull ##### and dosen't know what she is talking about.
Senior User
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the truth
A rule of thumb that I heard onces was:
i) anything under 400 cu.in. is a small block
ii) anything over 400 cu. in. is a big block
there are a few acceptions to this though (i.e. the 332 was a big block). The 400 ford is in a family of engines that are considered small blocks but the 351M/400 uses big block transmission bolt pattern.
My conclusion: it's a hybrid!!
Fordy
i) anything under 400 cu.in. is a small block
ii) anything over 400 cu. in. is a big block
there are a few acceptions to this though (i.e. the 332 was a big block). The 400 ford is in a family of engines that are considered small blocks but the 351M/400 uses big block transmission bolt pattern.
My conclusion: it's a hybrid!!
Fordy
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the truth
[updated:LAST EDITED ON 08-Apr-02 AT 01:10 PM (EST)]Okay,I finally found it.
Show that person this photo.
This is a Ford Performance reference book that they published hundreds of thousands of.
BTW< It's a 400 not a 400M
The only M motor was the 351M
https://www.ford-trucks.com/user_gallery/sizeimage.php?&photoid=3595&.jpg
[i][font color=blue]Dennis[/font][i]
[font color=red]Calgary,Alberta,Canada[/font]
http://www.clubfte.com/users/mil1ion/Minimorleytruck.JPG
[i][font color=green]
http://www.clubfte.com/users/mil1ion/Mil1ion.html [/font][i]
[font color =green] Please Don't Ask Me Any Tough Questions,
"I'm Saving My Memory For When I Develop Alzheimer's" [/font]
[font color=blue]78 F-150 429CJ,Silver,Explorer Pkg.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon [/font]
Show that person this photo.
This is a Ford Performance reference book that they published hundreds of thousands of.
BTW< It's a 400 not a 400M
The only M motor was the 351M
https://www.ford-trucks.com/user_gallery/sizeimage.php?&photoid=3595&.jpg
[i][font color=blue]Dennis[/font][i]
[font color=red]Calgary,Alberta,Canada[/font]
http://www.clubfte.com/users/mil1ion/Minimorleytruck.JPG
[i][font color=green]
http://www.clubfte.com/users/mil1ion/Mil1ion.html [/font][i]
[font color =green] Please Don't Ask Me Any Tough Questions,
"I'm Saving My Memory For When I Develop Alzheimer's" [/font]
[font color=blue]78 F-150 429CJ,Silver,Explorer Pkg.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon [/font]
Senior User
Joined: Sep 2001
Posts: 210
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From: Lincoln, Rhode Island
the truth
I believe the true difference between big-block and small-block has to do with bore spacing 4.00" and under bore size is a small block while anything larger is considered a big-block. examples are 396 chevy is a big block and the 400 chevy is a small block. The ford FE block is considered a big block and it ranges the size from 360 to 428. The 400 is usually just considered a inbetween size due to the fact is shares significant simillarities with both and is usually just refered to as a cleveland block engine but I think it is actually a small block.
400m
400m
Mountain Pass
Joined: Sep 2000
Posts: 233
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From: Eagle River, Ak
the truth
Small block and big block are irrrelevant terms for Fords.
Chevy basically has the 2 engine amilies, ford has more than that and the differences are more than just block size.
So I prefer to use neither term for Ford engines.
1970 Mustang Grabber Sposrtsroof. Rather non-stock...
1965 f100
Chevy basically has the 2 engine amilies, ford has more than that and the differences are more than just block size.
So I prefer to use neither term for Ford engines.
1970 Mustang Grabber Sposrtsroof. Rather non-stock...
1965 f100
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the truth
I read this somewhere (On this board)...
If a family has an engine that is > 400, it is considered a big block. If there wasn't one > 400, then it is considered a smallblock.. Of course, this only pertains to ford..
I may be dead wrong here, but it does make sense... To me anyways...
Later
Riley
If a family has an engine that is > 400, it is considered a big block. If there wasn't one > 400, then it is considered a smallblock.. Of course, this only pertains to ford..
I may be dead wrong here, but it does make sense... To me anyways...
Later
Riley
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