351m or 400 identification

Reply Subscribe

Thread Tools

Search this Thread

May 1, 2003 | 05:31 PM

Ford Truck Racer

Thread Starter

Elder User

Joined: May 2002

Posts: 627

Likes: 0

From: Claremore, Ok 74017

351m or 400 identification

I am installing a motor in my brothers truck and he said it had a 351m. But after looking at it, it looks more like a FE. This is a 78 F-150. So if someone could post a picture of what a 351M would look like and where I could find a number stamped on the the block this would help a lot. Thanks.

May 2, 2003 | 04:42 AM

ferguson777

Posting Guru

Joined: Apr 2002

Posts: 2,244

Likes: 1

351m or 400 identification

If no one responds to this note, try this;

There is one of the Bronco sites that has an article on the history, care and feeding of a 351M/400M. If you do a search on the WWW using something like " 351M AND performance" you'll probably find it. It has some pictures of what they look like as I recall.

Additionally, the FE has 5 valve cover bolts per head, the M's and C's have 8 ( and the W's have 6). The M's also have the dipstick going into the pan rather than the block - not sure what the FE's have.

Later,

May 14, 2003 | 08:29 PM

havi

I'll have the Roast Duck

Joined: Jul 2002

Posts: 9,622

Likes: 110

From: Northshore, MN

351m or 400 identification

thermostat housing is a tell-tale sign determining what type motor you have. Also, the FE motors have their intake manifold -to- head-surface more significant than the 400...hope this helps

May 14, 2003 | 11:54 PM

Ford_Six

Hotshot

Joined: Oct 2002

Posts: 18,488

Likes: 22

From: The Big, Oregon

351m or 400 identification

If the intake forms part of the valve cover mating surface, that's an FE. If not, it's a 351m or 400 (most likely). If it is an FE, that's not stock for that truck. Also, if it had a big block before, an FE won't fit, they used a different bellhousing.

Aug 22, 2003 | 09:08 PM

mindless

New User

Joined: Aug 2003

Posts: 1

Likes: 0

351m or 400 identification

on a 351m look on front end of the heads if it is a 351m it has a m stamped on it.

Aug 26, 2003 | 10:10 PM

Ecuri

Elder User

Joined: Jun 2003

Posts: 886

Likes: 1

From: Houston/Hope BC

351m or 400 identification

And the FE's use a rocker shaft whereas the M's are pedastal mount valve train.... and the valve covers on the FE come to an angle on top rather than a flat. And the FE has a seperate timing cover rather than part of the block. Pretty sure, Is that all correct?

Aug 28, 2003 | 10:04 PM

Brian460

Posting Guru

Joined: Jul 2002

Posts: 1,785

Likes: 0

From: Paola, KS

351m or 400 identification

And they stopped using FE motors in '76, so unless somebody swapped it, it is probaly a 351M/400

A 351M/400 has a diagonal bolt pattern on each exhaust port and a FE has a vertical pattern on each port.

Also true about the timing cover.