block ID
Posting Guru
Joined: Aug 2000
Posts: 1,127
Likes: 3
From: (near) Denver USA
It is a late production 351M/400, with a casting date (1L10) of November 10, 1981. It was manufactured during the last model year (1982) that the 351M/400 was produced.
Since the same block was used for both 351M and 400 engines, you have to identify the crankshaft to determine which one it is.
Check this page for more info about the crankshafts:
http://home.earthlink.net/~bubbaf250/parts/parts02.html
Since the same block was used for both 351M and 400 engines, you have to identify the crankshaft to determine which one it is.
Check this page for more info about the crankshafts:
http://home.earthlink.net/~bubbaf250/parts/parts02.html
Senior User
Joined: Oct 2003
Posts: 347
Likes: 0
From: in a house
bubbaf250, about your "can't use a wire in the spark plug hole".
if you measure the stroke and get 4" you have a 400 or a stroked original 351M.
if you get 3.5" you have a 351M or a destroked originally a 400 (which someone should be commited for ever doing).
so what I'm getting at, I agree this is not for measuring the authinticity of the original intent of the block but aren't you getting the answer for what is it now?
if you measure the stroke and get 4" you have a 400 or a stroked original 351M.
if you get 3.5" you have a 351M or a destroked originally a 400 (which someone should be commited for ever doing).
so what I'm getting at, I agree this is not for measuring the authinticity of the original intent of the block but aren't you getting the answer for what is it now?
Posting Guru
Joined: Sep 2003
Posts: 2,263
Likes: 0
From: N. Florida - The "No 4x4
Originally posted by bubbaf250
. . . http://home.earthlink.net/~bubbaf250/parts/parts02.html
. . . http://home.earthlink.net/~bubbaf250/parts/parts02.html
Thank you.
(and go finish the engine recipes, please)
Posting Guru
Joined: Aug 2000
Posts: 1,127
Likes: 3
From: (near) Denver USA
ranchero,
The linked page refers to measuring crankshaft stroke, not the block. The issues are the same, regardless of the origin of the block.
The problem is that there is no practical way you can get a reliable measurement. I have seen several cases where measuring with a coat hanger yielded less than 3.5" with a 400 crankshaft.
ctfuzzy,
Thanks for the kind words.
I have lots of data, but little time to do much with it right now. For two years, I've been saying that I'll get to it in the next few months.
The linked page refers to measuring crankshaft stroke, not the block. The issues are the same, regardless of the origin of the block.
The problem is that there is no practical way you can get a reliable measurement. I have seen several cases where measuring with a coat hanger yielded less than 3.5" with a 400 crankshaft.
ctfuzzy,
Thanks for the kind words.
I have lots of data, but little time to do much with it right now. For two years, I've been saying that I'll get to it in the next few months.
Thread
Thread Starter
Forum
Replies
Last Post
66BlueOval
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
15
May 9, 2025 03:58 PM
jacob_9249
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
2
Jul 26, 2008 08:04 AM
