Boss 351 exhaust manifolds

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Heardatbeat

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My Car
1971 Mach 1
Hey ya'll so a few years ago I posted about trying to decipher my 351C and wether it had Boss heads and then CC heads because the previous owners decided to paint the Grabber Lime Mach 1 into a Pewter Silver Boss 351. Well due to a head gasket failure I had to pull the heads and finally found out they are CC heads. Now I bought a set of Sanderson Headers off craigslist and turned out to be for a truck (oops) well I did some research on the exhaust manifold and according to Mustangtek they are Boss 351 exhaust manifolds due to the fact that the ports are 2 1/4 and not 2 inches even. Is this correct or am I missing more info?

20200315_190549.jpg

 
That port is also 2 1/4. The one where the exhaust exits. It got dark so I could not get a photo. I'll post one tomorrow when it is day time.

 
There are many ways to ID, measure and confirm. Boss openings have a 3 pass machining opening , that is SHORTER than the outlet like on a non Boss.

Since you aren't working with a caliper (or a light) .......start with the date code of the manifold. IF it isn't an 0K through a 1E then just stop worrying about it.

Mark

 
There are many ways to ID, measure and confirm.    Boss openings have a 3 pass machining opening , that is SHORTER than the outlet like on a non Boss.

Since you aren't working with a caliper (or a light) .......start with the date code of the manifold.    IF it isn't an 0K through a 1E then just stop worrying about it.

Mark
One of them says OK23. The other is kind of hard to make out. I will take my manifolds to work and measure them there.

 
There are many ways to ID, measure and confirm.    Boss openings have a 3 pass machining opening , that is SHORTER than the outlet like on a non Boss.

Since you aren't working with a caliper (or a light) .......start with the date code of the manifold.    IF it isn't an 0K through a 1E then just stop worrying about it.

Mark
One of them says OK23. The other is kind of hard to make out. I will take my manifolds to work and measure them there.
Well that is a good start !!!   The opening should be flat on the end of "donut" for a boss (sharp and longer) for the 351C

 
There are many ways to ID, measure and confirm.    Boss openings have a 3 pass machining opening , that is SHORTER than the outlet like on a non Boss.

Since you aren't working with a caliper (or a light) .......start with the date code of the manifold.    IF it isn't an 0K through a 1E then just stop worrying about it.

Mark
One of them says OK23. The other is kind of hard to make out. I will take my manifolds to work and measure them there.
Well that is a good start !!!   The opening should be flat on the end of "donut" for a boss (sharp and longer) for the 351C
Not sure. I will take some more photos when I measure with the calipers. I will do so here in the next hout or so.

 
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Definitely not Boss. The I.D. of the ports measure 2 inches. What does a decent pair fetch for? I am putting headers on mine.

 
On your heads, the inlet ports are 2.50" x 1.75", the exhaust are 2" x 1.74". On the underside of the inlets, you'll find the casting info. as an example, mine are D1AE-GA which are 1971 4 V CC heads. The date code is cast between the valves stems. Also, there may be a * cast into the front top corner (known as a 4 dot) which indicates the 4V  62.8 cc CC heads. A listing I have shows the Boss heads to be D1ZE-A or B, which are 66.1cc CC heads, but with screw in adjustable rocker studs and guide plates.

The exhaust for the Boss has a casting number D0AE-9431-G, same as 70 351C 4V, but with 2 1/4" opening which I assume is the outlet. There is also a D1ZE-9431-BA listed for the Boss 351 with 2 1/4" opening.

Hope that helps, but it seems like you have a regular 4V . What are your heads numbers?





 
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