The original 272 CID engine is back in the truck and has had the break in start up procedure completed. Sounds sweet till I removed the exhaust system for improvement.
The existing exhaust down pipe / header pipe from my stock manifold is two inches, 2" OD. Looking at the stock manifold, it appears the original size of the down pipe / header pipe could have been larger, like 2 1/8 inch. The inside diameter of the driver side exhaust manifold is at least 2 1/8". I have two similar truck engines and both exhaust manifolds are the same.

So does anyone have an exhaust pipe/header pipe where they could measure the OD? I figure now is the time to make it right while the front clip is off the truck. BTW, this is a stock rebuild.

Thanks in advance.

Edit: The second engine mentioned is from a '56 F-100 and appears identical to the original in the F-350 so exhaust diameter is probably the same on the F100
Pictures are before final wrap up. Engine needs final valve adjustment, newly painted covers installed and new steel fuel line. And of course, the exhaust system replaced.

 

Hi raytasch ,
According to my parts book all 54/56, models C,D,Y & T with 8 cylinder engines had 2" O.D. dia. down pipes.
Hope this helps, Old Ugly

 

Thank you, sir. Guess what I have is correct and I'll stay with it. Reps.