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Topic: 351W C6 to a 351M (Read 1761 times) previous topic - next topic

351W C6 to a 351M

my buddy wants to know if the c6 from my 351W will bolt up to his 351 mod


thanks a bunch

351W C6 to a 351M

Reply #1 –
nope, sure won't.
351M/400 share the bell pattern with 429/460
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

351W C6 to a 351M

Reply #2 –
Quote from: FordTruckFreeek;108295
nope, sure won't.
351M/400 share the bell pattern with 429/460


I beg to differ.

mid 70 full size LTD, T Bird and Cougar have 351M from factory and they do share same bell housing with Windsor family.

The big question is.....

Which 351M does BlackJack have?

351W C6 to a 351M

Reply #3 –
black jack has a 302 :D

geordans 78 tbird has the 351 mod with the 2 barrel

351W C6 to a 351M

Reply #4 –
Quote from: KwikFord;108296
I beg to differ.

mid 70 full size LTD, T Bird and Cougar have 351M from factory and they do share same bell housing with Windsor family.


351M/400 DO NOT have the windsor trans bolt pattern, they have the 'big block' bolt pattern.

Those 70's cars I believe used the FMX with the m's didnt they?
1980 birds X 3, 1982 bird, 1984 XR7, 1988 TC

351W C6 to a 351M

Reply #5 –
All 400's and 351m's had BB bolt patterns.  They came with C4's and FMX's and some trucks had sticks.  The c6 from his windsor won't bolt up.

351W C6 to a 351M

Reply #6 –
I do know the '76 Ranchero GT that i used to have had a 460 and a C6 in it...would do a one-wheel-peel as long as you kept your right foot planted, too :cool:

And...as mentioned a time or two in this thread already,
351M/400 ARE THE SAME BOLT PATTERN as the 385 series "big blocks" (429-460)
In fact, distributors will interchange as well...
Trust me, they are the same! I've swapped a 460 into a 351M truck.

Was a post on FTE sometime back...i think the gist of it was that the FMX was a car only transmission..and I think by 1978 that big ole Tbird most likely woulda had a C6 anyway...
i could be wrong on the trannies tho..
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

351W C6 to a 351M

Reply #7 –
There were a few early '71 400's that had the small block pattern, but they are few and far between... All 351M have the BB pattern...

Quote from: FordTruckFreeek;108303
Was a post on FTE sometime back...i think the gist of it was that the FMX was a car only transmission..and I think by 1978 that big ole Tbird most likely woulda had a C6 anyway...
i could be wrong on the trannies tho..

My Pop had a '79 Cougar 351W and it still had the FMX tranny... Wifes aunt also had a '79 with a 351M that had the FMX. My guess is they went with that tranny because of the removable bell...

351W C6 to a 351M

Reply #8 –
both of my cougars 302 and 351W had the FMX  the 77 bird had a 400 and C6 and the 351M cougar had an FMX

I have a big block bell for an FMX if interested

351W C6 to a 351M

Reply #9 –
Quote from: 88turbo;108342
both of my cougars 302 and 351W had the FMX  the 77 bird had a 400 and C6 and the 351M cougar had an FMX

I have a big block bell for an FMX if interested


Yep, I think I need to do more reading on the transmissions...I will admit that's one area I'm not as knowlegdable on..:dunce:
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

351W C6 to a 351M

Reply #10 –
i got a 351m in my truck from a 79 cougar and it bolted up fine. up untill now i was sure the 351m/400 had the bb bolt pattern...?

351W C6 to a 351M

Reply #11 –
Quote from: Nate;108368
i got a 351m in my truck from a 79 cougar and it bolted up fine. up untill now i was sure the 351m/400 had the bb bolt pattern...?

They do.
What motor was in the truck, a different 351m?
On a different note, I've seen a lot of people swear AT the 351m/400 because they over-revved it, and tore it up, not realizing it is a low rpm, torque producing engine. Parts aren't as common for them as a 351W, let alone a 5.0, but built right, they'll out-pull a modern 351w everytime.
Kinda peeves me to see people yank them out, and set the truck up for a 351w, when a 429, or 460 will bolt right in. (after changing mounts, of course)

But yes, for the LAST TIME, 99.9% of 351m/400 engines have the "385" series bellhousing bolt pattern.
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

351W C6 to a 351M

Reply #12 –
Quote from: FordTruckFreeek;108370
Kinda peeves me to see people yank them out, and set the truck up for a 351w, when a 429, or 460 will bolt right in.


My buddy wanted to do thast in his current project 78 f250, I cuffed him and threatened his life if he pulled the m for a 351w. I think it werked
1980 birds X 3, 1982 bird, 1984 XR7, 1988 TC

351W C6 to a 351M

Reply #13 –
yeah, im keeping the M because i want to do a fuelie 460 swap with its manual transmission.