Boss 351 Engine or not??

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1971 Mustang Mach 1, M code, 4 speed.
I can't add anything new to whether it is or is not a Boss motor, but man, that's a nice looking Mach 1 you have. Nice score! 

I'm also glad you were not offended by the comment on the gear clamps. It is never my intention to ever offend anyone, but I just HATE those things. Yes, gear clamps have there uses and are very serviceable, just not on fuel lines or anywhere else failure can cause a bonfire!

Oh boy, I just spotted another huge no-no for a 71. PLEASE get rid of that damn flex fan. Not only is it incorrect for you car, but they are highly dangerous especially at 45+ years old. I would go for a good NEW clutch fan assembly unless you want originality. If so, you'll need a 4 blade and the correct adaptor.

 
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Djustham

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Thanks for coming back, posting photos and keeping involved here and with your car !     I think we all assumed it was a project and ratty. LOL  Very nice car.

Though not the photos , I hoped to help tell.....at this point I would simply (get a look at the balancer) and TELL US "does it sound like a SOLID cam shaft".   If it doesn't and doesn't have a 2 inch balancer........seeing the lack of Boss parts and the pletora  351C parts leave it at that!   Move on to your work at hand.   

To your idea of "working on" what to do, I would adress all of the WRONG /missing items from what I CAN see it the photos.   Look at photos of hose routing for air cleaner AND CONFIRM "what is the hell did they run the canister hose to" ??????!!!!   I'm not sure I would put effort into the 2Brl air cleaner - rather consider finsihing the car with the correct ram air!  If you detailed the engine compartment and un "H" coded it you would kill two birds with one stone!

View attachment 43633
It’s has a 4v carb but it doesn’t have the ram air hood . So based on that is the air cleaner correct?

 

SVO2SCJ

Zip Tie Mechanic - can I help you?
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NO. and yes.   Some of the pieces will work, THINK the correct lid is chrome. Others here will know , as  I never owned anything but a Boss 351 when it comes to 71's.   Spend some time looking at correct cars on Google (just that is an art to filter through all the Frankenstein's)! 

We knew it had a 4 barrel , from the use of the CA manifold.  (we just don't know if it isa spread bore or if the manifold was cut up to use a square bore.  Taking in photos is an art too.  Where as some photo entire engines, others want to see specific parts up close!    Less can even video !!   Going too fast, jumping around and not spending time in one location to be able to look at all the pieces.  

Mark

P.S.  Some times the best info comes from the prior owner photos !!    It gives you the ability to see a car when bought, how it was tricked out and if any real use!       Funny, we took a car to an auction and everyone was asking "did you just finish the car?"   (car was restored 5 years before)  TO which they said "MAN that is clean, you must not drive it!" (Car was drvien to Reno twice and Washington state from AZ that year)  Theirs on the other hand you could smell the paint degassing still!  

 

Djustham

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Boss engine or not, you have one nice looking ride there.  Enjoy it regardless!

However, as others have said, you can take a look at the damper, which is probably the easiest thing to do.  Other fairly simple things to check would be to pull a valve cover to see if you have the Boss screw in studs/adjustable rockers.  I believe someone else mentioned it already, but you could pull a spark plug and take a look at the piston with a snake camera.
Its got like a 2" damper. Ive got a snake camera, what should I look for on the piston?

 

Djustham

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Is the oil sender at the back of the intake manifold an indicator of a Boss 351 engine? Thought I read that somewhere 

 
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Djustham, the oil pressure sender for ALL 335 series engines (351C, '75/351M, and 400) were in the block behind the intake manifold. The only difference was the sender used for a gauge or idiot lights. 

 

trillizo_y_uno

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Its got like a 2" damper. Ive got a snake camera, what should I look for on the piston?
Stanglover posted a picture of a Boss piston earlier in this thread.  See if your pistons look like that.  You might also be able to use the snake camera to look for the screw in studs if you don't want to pull off a valve cover.

 

Hemikiller

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Take a look down into the oil filler, or pull a valve cover. You should have screw in studs and guideplates. The guideplates should be visible. 

http://www.boss302.com/heads.htm

One true way to knock it out of the park is to get the partial VIN stamping off the back side of the block, below the driver side head. 70 and early 71 model year blocks had it below the passenger side head. You can send that VIN to Kevin Marti and he can tell you if it's a B351 VIN or not. 

 
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