351C or 351M
Posting Guru
Joined: Jul 2015
Posts: 2,239
Likes: 5
From: Northeast Ohio USA
Moderator
Joined: Nov 2007
Posts: 22,415
Likes: 92
From: Denver Metro Area, CO
And was resurrected by a newbie who seems to have joined exclusively to submit those two posts, it looks like he's basically trying to say that Franklin2 is wrong and he's right - in exceedingly poor, difficult-to-understand English - in a 3yo thread.
I'll delete his posts and all this chatter if it's OK with you guys, let me know.
I'll delete his posts and all this chatter if it's OK with you guys, let me know.
Freshman User
Joined: Dec 2015
Posts: 29
Likes: 0
From: Mesa, AZ
I'm wondering if my pickup has a 351 Cleveland or a 351 Modified. All along I have been told its a Cleveland and I have been ordering parts for a Cleveland and they all fit and work properly, but when I took my starter out to put it in my new 75 F150 the casting number on the engine block was D7TEA35 and above that upside down was 9819. I searched around on the internet and i can't find a D- code 351 Cleveland. I can find D-code 351 Modifieds. I've had 6 mechanics tell me its a cleveland by measuring from the water pump to the intake, counting valve cover bolts, the size and many other things. I'm really confused here and I'm not sure what to do all of the Cleveland parts I've been ordering have fit just fine and it operates just fine. Were they all wrong? Any suggestions on this? 
I have a 351C with C-6 Trans (which was offered in small or big block pattern) in my 56 F100. Downside to the C is swapping a 2 BBL to 4BBL. You either have to buy an aftermarket intake or change out the entire top end of the motor. (Heads and intake) if wanting to use Ford parts.
BTW, they can be easily built to rev to 7k with no issues, so although a very limited production and rare motor, they are pretty bad ***.
I tend to like the oddball motors. I like openeing my hood at a show and showing something out of the ordinary. Downside to that is cost. Parts are always way more expensive.
My Headers for my 67 Cougar with factory S code 390 just ran me 700! As apposed the a 302 would be about 250-350.
Moderator
Joined: Nov 2007
Posts: 22,415
Likes: 92
From: Denver Metro Area, CO
ALL of the 335-series engines - 351M, 351C, 400 - use a fuel pump with the vertical mounting bolts; the V8 Windsor engines (and all other engines, 335 is the only one to use this configuration) use side-by-side.
Freshman User
Joined: Dec 2015
Posts: 29
Likes: 0
From: Mesa, AZ
Thanks for clarifying
Moderator
Joined: Nov 2007
Posts: 22,415
Likes: 92
From: Denver Metro Area, CO
That works, too; 335-series use 8 I believe, Windsors use 5 or 6 (I forget).
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 6 Best Deals Available on New Fords & Lincolns Right Now
Brett Foote
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Verdad Gallardo
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Moderator
Joined: Jan 2001
Posts: 57,027
Likes: 2,762
From: Virginia
Easiest way to tell a 351c from a 351m/400 is the casting step behind the distributor hole; The 351m/400 has a step, the 351c is flat and level to the intake end seal area.
That's one thing I will knock Ford for; They changed their minds too many times, and when they did nothing was compatible. They are still doing it too.
That's one thing I will knock Ford for; They changed their minds too many times, and when they did nothing was compatible. They are still doing it too.
Freshman User
Joined: Dec 2015
Posts: 29
Likes: 0
From: Mesa, AZ
Easiest way to tell a 351c from a 351m/400 is the casting step behind the distributor hole; The 351m/400 has a step, the 351c is flat and level to the intake end seal area.
That's one thing I will knock Ford for; They changed their minds too many times, and when they did nothing was compatible. They are still doing it too.
That's one thing I will knock Ford for; They changed their minds too many times, and when they did nothing was compatible. They are still doing it too.
GM was genius with the 350. Just kept tinkering till they got it right.
But with that said, I will never under any circumstances put a GM motor in any of my Fords. Im of the mindset that Fords engineers are better. Why? Simple. Fords smaller 302 out performs GM's 48 cubic larger 350. Plus it was Ford that slapped Ferraris ***. Not GM 👍🏻
Moderator
Joined: Jan 2001
Posts: 57,027
Likes: 2,762
From: Virginia
I disagree with that. Ford's small v8's and the chevy v8's are very similiar in design. They both can be built for power. Ford's downfall was always the heads. Yes, they made some decent heads, but the majority of the heads that they put on their everyday cars are no good for making horsepower. If you want to build a Ford engine, the heads are the first thing to go or be modified.
Cargo Master
Joined: Mar 2002
Posts: 3,132
Likes: 219
From: W (BY GOD) V
351C/351M/400: All have 8 valve cover bolts per side. There is no timing cover per se, just a flat engine front cover plate.
The fuel pump bolts to the left (drivers) side of the engine block using a 6 & 12 o'clock bolt pattern, the only V8 fuel pump to have this pattern, as all the others are at 3 and 9 o'clock.
351C = 1970/74 Ford/Merc Passenger Cars/Ranchero's only.
351M = 1975/79 misc FoMoCo Passenger Cars; 1977/79 F100/350; 1978/82 Bronco; 1980/82 F150/350.
400 = 1971/79 misc FoMoCo Passenger Cars; 1977/79 F100/350; 1978/82 Bronco; 1980/82 F150/350.
How could 9819 refer to September 19, 1979? What does the 8 refer to?
This would be correct: 9J19 = September (J) 19, 1979 (9). A = January, M December, the letter I is skipped.
I suspect the 8 is actually a B (February) ~ 9B19
Many M-block (351M/400) engine blocks have a 5/8" tall raised web just left of the distributor hole, on the top of the block. However, not all M-blocks have that web, as this photo (and the previous photo) of a 1978 MCC block shows.Some people say you can distinguish an M-block from a 351 Cleveland block by that web. It's true that no 351 Cleveland blocks have that web, but not all M-blocks do either. While presence of the web rules out a 351 Cleveland, absence of the web does not rule out an M-block.
SOURCE - M-Block 351M/400 Photo Archive
Last edited by KULTULZ; Nov 28, 2025 at 02:07 AM.
Moderator
Joined: Jan 2001
Posts: 57,027
Likes: 2,762
From: Virginia
Cargo Master
Joined: Mar 2002
Posts: 3,132
Likes: 219
From: W (BY GOD) V
Thread
Thread Starter
Forum
Replies
Last Post
Super Econoline
1973 - 1979 F-100 & Larger F-Series Trucks
15
Oct 25, 2012 09:35 PM
Fix_Or_Repair_Daily
1973 - 1979 F-100 & Larger F-Series Trucks
4
Jan 6, 2011 10:11 PM
ford0625
335 Series- 5.8/351M, 6.6/400, 351 Cleveland
7
Dec 22, 2009 03:14 PM