I have a 1970 442, 4 speed olds. I ordered some flotech headers. The box says for a 442 Olds and a firebird with either a 350-403.
I was a bit concerned so looked up Summit to see what is going on.
The 11150FLT headers fit 442 350-400... I did not know 442 came with a 350???
The 11154FLT says fits 455 and 400.... but hang on, do they both fit 400?? that means they both fit 350 and 455... bit confused here, can anyone help please

 

The 72 442 could have a 350

You need the 455 headers

Idk about the 400 fitment

Some on here have had some difficulty w the flotech fitting well

 

Stay away from Flowtech, you get what you pay for.

 

I moved your post to it's own thread because, frankly, it wasn't directly related to that seven year old thread anyway.

As for the header fitment issues, once again all small blocks (260, 307, 330, 350, and 403) are externally identical. Small block headers for one will fit any of the others in the same chassis (note that the 1985-1990 307s with 7A heads have tiny ports that may not seal properly to other SBO headers).

All big blocks (400, 425, 455) are externally identical and again, headers for one will fit any of the others in the same chassis. Small block and big block headers will physically bolt to the exhaust flange on any Olds motor, but the deck height differences will nearly always mean that there will be interference problems when you cross applications.

Oh, and as always, catalog application listings are frequently wrong.

 

The 71 Cutlass I just bought has a 350 in the car, but some one put big block header on the car, therefore they do hang down lower and someone beat the heck out of them for clearance on the frame and suspension, take every ones advice and buy the correct headers and a quality header or what i am going to do when i put a 455 in the car and just run exhaust manifolds.

 

I have a set of Hooker headers for a small block listed in the classifieds...