Are the 351C big block engines?

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classicsguy

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I have seen many 71-73 Mach 1's on craigslist and E bay that have the M or Q-code 351C 4V engine advertised as a Big Block Mustang.

I am sure they are still small block engines since in order to be considered Big Block for me is that the engine must be at least 390ci and this one is not available in the 71-73 Models but the 429 was and that one would be considered Big block.

Am I correct and why would the 351 be considered big block by some owners....?? It may have the power but not the cubic inches

 
If the words big block appear in an ad when it is a 351c, either the seller doesn't know any better or they are just hyping up the excitement about the car.

 
You are correct, 351C is a small block, as are it's 335 series cousins, the 351M and 400M. It does get confusing, all FE blocks are considered to be big blocks, even the 332 and 352 engines. The 385 series is big block (429s and 460s). A lot of people don't have a clue as to what they have, and think that "big block" sounds better than calling it just a 351C, which is enough.

 
351c is the first small block that could take out the big blocks on the track...Years of ford tech went into making a motor that was so good..It was banned from most racing....Had a smaller crank than any ford small block at the time...Meaning it could spin higher rpm's...Better webbing...Higher tech block casting..For a lighter but stronger block...Huge heads...What a motor...i would allmost put it in the class of small block with big block heads..lol<~~ but still that doesnt give it justice...Its more than that...Its a block all in its own class.

btw cubic inches doesnt not make it a small or big block....Pontiac and olds made a 350ci big block...and fords 352 is a big block too...if you put big heads on a small block...I wont ever call it a big block..cause the block is still small..lmao

 
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It is a big block. The heads belong on a 429 and the intake

valves are bigger than the 460 police interceptor; 2.19 vs 2.07.

You can stick a tennis ball in the intake port on the head.

It is a big engine.

mike

 
It bolts only to small block pattern bell housings also.

 
Who Cares?

Big block/small block. The definitions are tossed around. In the end it really doesn't matter.

It's one of the best engines of its time. We know that for sure.

If someone asks me I say small block, based on the bolt pattern. But we know the other 335 engines including the 351M and 400M had the 'big' bell housing pattern (a few 400's came with the small pattern)

I used to spend time telling sellers 'that is not a cleavland, it is probably a windsor' only to be told I was wrong. I got tired of it. :)

 
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I agree i call it a cleveland. The original small block/ big block designation was to identify Chebby engines it does not really translate to other makes.

In the Ford world most people use "small block" to mean windsor(260 to 427 cubes),big block generaly means 385 series (429 to 600+ cubes). Everything else, IMHO is a FE, a Cleveland, a Mod(modular) or a flathead.

I expect to see a 429 type motor in a 71-73 Mustang if it claims to be a big block.

 
Ive had that question a time or two and most try to push the windsor because its cheaper to build etc but the 351C is here to stay in my car, its rare and built to rev.

 
I have seen many 71-73 Mach 1's on craigslist and E bay that have the M or Q-code 351C 4V engine advertised as a Big Block Mustang.

I am sure they are still small block engines since in order to be considered Big Block for me is that the engine must be at least 390ci and this one is not available in the 71-73 Models but the 429 was and that one would be considered Big block.

Am I correct and why would the 351 be considered big block by some owners....?? It may have the power but not the cubic inches
The 351c is a small block. It has a small block bolt pattern for the bell housing and engine mounts,and the heads can be bolted on to other small block fords. Ask yourself, if the 351c is a big block ,then what is a boss 302? Thats my two cents worth and I am sticking to it! Whisnane

 
I have seen many 71-73 Mach 1's on craigslist and E bay that have the M or Q-code 351C 4V engine advertised as a Big Block Mustang.

I am sure they are still small block engines since in order to be considered Big Block for me is that the engine must be at least 390ci and this one is not available in the 71-73 Models but the 429 was and that one would be considered Big block.

Am I correct and why would the 351 be considered big block by some owners....?? It may have the power but not the cubic inches
The 351c is a small block. It has a small block bolt pattern for the bell housing and engine mounts,and the heads can be bolted on to other small block fords. Ask yourself, if the 351c is a big block ,then what is a boss 302? Thats my two cents worth and I am sticking to it! Whisnane
X2. That's it in a nut shell. Its a small block.

 

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