273 headers

[FLY 9999]

Just redid the motor and trans for a U/SA Belvedere. Just realizes that I need headers. I've seen Hedman headers but there a universal 273-360 and the 273 exhaust ports are different in size than the 318,340,360. Any help is gtreatly apprcoated. Thank you.

 

[toolmanmike]

Just redid the motor and trans for a U/SA Belvedere. Just realizes that I need headers. I've seen Hedman headers but there a universal 273-360 and the 273 exhaust ports are different in size than the 318,340,360. Any help is gtreatly apprcoated. Thank you.

The 273/318 ports are the same size. 340/360 are bigger. There are no headers made specifically for 273's that I have ever seen. (and that goes back to the early 70's.)

 

[j-c-c-62]

Even if they are slightly larger headers on smaller 273 ports, it doesn't matter much, if not for all out racing, as anyone with a 273 is not seeking great output that a 360 wouldn't far surpass for nearly the same weight and size.

BTW, I also have a warmed over 273 in a b body, the motor surprised me how peppy it is.

 

[33 IMP]

He's building a stocker for U/SA. A 360, or anything else is NOT an option. And, he IS building it for all-out racing! And I bet he is seeking great output.

I'm wondering if you could graft in some smaller header tubes at the flanges, and keep the larger tubes down stream, as a sort of step header. Might be able to modify a small sbc header.

 

[j-c-c-62]

He's building a stocker for U/SA. A 360, or anything else is NOT an option. And, he IS building it for all-out racing! And I bet he is seeking great output.

I'm wondering if you could graft in some smaller header tubes at the flanges, and keep the larger tubes down stream, as a sort of step header. Might be able to modify a small sbc header.

Yes, I see that, my mistake, maybe fab a 1/2"? steel transition adapter plate between head and header, or just spend the bucks for a custom stepped header?

 

[33 IMP]

Yes, I see that, my mistake, maybe fab a 1/2"? steel transition adapter plate between head and header, or just spend the bucks for a custom stepped header?

I like your spacer/adapter idea. But I think he's worried that a typical 340/360 header will have too-big tubing
I remember the Stahl headers for the tiny sbc's in Jr stockers were TINY!
(55-57 chevies with 265/283/292)

 

[FLY 9999]

! 1/2 transition to 1 5/8 really bring out the low end power that this combo needs. A friend who ran a similar 273 had 1 1/2 headers that came from Honest Charlies a good while back. Thought that someone might knowlwdge.