[Luiz]

Hi, there's a guy down here in Brazil selling a '77 Ford 351M engine. Would it fit a '69 Mustang without adaptation? I mean things like fabricated engine mounts, etc. The car has presently a 302 Ford. Thanks, Luiz

[Silver Shaddow]

Don't know about the engine mounts, but the bellhousing to engine block bolt pattern is different. The "M" series engines used the Ford big block bolt pattern which is different to the normal 351/302 Windsor and 351/302 Cleveland small block bolt pattern.

[Luiz]

Originally Posted by Silver Shaddow

Don't know about the engine mounts, but the bellhousing to engine block bolt pattern is different. The "M" series engines used the Ford big block bolt pattern which is different to the normal 351/302 Windsor and 351/302 Cleveland small block bolt pattern.

Thanks for the information. I guess that there's too much hassle involved in this swap. The car belongs to a friend of mine and he'd have to find a Ford big block trans. Better find a 351W. Chevy is more rational on this. The engines, small or big block, use the same pattern.

[Silver Shaddow]

Yup, the 400M truck motor also uses the Ford big block bolt pattern.

I think you are right, a standard passenger car Cleveland or Windsor engine would be better, and I believe both also have a higher compression ratio and rated horsepower than the "M" truck motors.

[Luiz]

Originally Posted by Silver Shaddow

Yup, the 400M truck motor also uses the Ford big block bolt pattern.

I think you are right, a standard passenger car Cleveland or Windsor engine would be better, and I believe both also have a higher compression ratio and rated horsepower than the "M" truck motors.

Not withstanding that probably the M engine parts are more expensive.

[techinspector1]

Originally Posted by Luiz

Hi, there's a guy down here in Brazil selling a '77 Ford 351M engine. Would it fit a '69 Mustang without adaptation? I mean things like fabricated engine mounts, etc. The car has presently a 302 Ford. Thanks, Luiz

I think this would be a reeeaaaaally bad swap.

[oldred]

Originally Posted by techinspector1

I think this would be a reeeaaaaally bad swap.

You got that right, a 351M would be a really bad swap even if it was a bolt in fit!

[Luiz]

Originally Posted by oldred

You got that right, a 351M would be a really bad swap even if it was a bolt in fit!

This engine seems to be the classic "boat anchor"

[junkyardjeff]

A 351-W will bolt in with only some exhaust modifications due to being about a inch taller. Jeff

[powerrodsmike]

A 351M/400 uses different motor mount placement as well as the BB bellhousing...Learned that one the hard way when I used a 351 cleveland for mocking up my motor mounts in a 54 Ford pickup that was going to get a 400 installed.

Later, mikey

[Luiz]

Originally Posted by junkyardjeff

A 351-W will bolt in with only some exhaust modifications due to being about a inch taller. Jeff

Forgot that detail... Thanks for making me remember. We now got a 351W with a small crack in one of the cylinders. Think that a sleeve wil do.

[Luiz]

Originally Posted by powerrodsmike

A 351M/400 uses different motor mount placement as well as the BB bellhousing...Learned that one the hard way when I used a 351 cleveland for mocking up my motor mounts in a 54 Ford pickup that was going to get a 400 installed.

Later, mikey

It seems that we are always learning in the hard way. After bolting a Edelbrock intake in my 283 I found that the alternator bracket would not fit...