What headers will fit a 77 highboy w/ a 400?

 

Do you want full length or shortys, painted, aluminized, ceramic, chrome or plain, chassis exit, fenderwell exit, tuned, not tuned, tri-y, 1 3/4 tubes, 1 5/8 tubes, o-ringed mounting flanges, machined mounting flanges, you just need to see what you want to spend and go searching, i dont know if any of the site sponsors carry headers, if not try summit racing or jegs
its all part of the fun
make sure it is a highboy, early 77 f-250 4x4, divorced transfer case, the late 77 has a different frame and probably headers too

 

its a highboy , divorced case and all, was wondering what other people had used , most headers for 400 in trucks say 77.5-on

 

I have a truck like yours ('cept it's a crew) and swapped in a 460 in place of a 351 M and then proceeded to find headers. I wouldn't have thought it would have been too hard to do. Lots of people swapping in the 460's right? I wanted try y's but couldn't find any that fit. Didn't matter if I got headers for Highboy years or '78/9 years. Header mfg just gave me crap and told me my install was wrong. Well, if you have seen a 460 in these trucks, there really isn't a lot of room to move them around in. The headers were so far off, that if I moved the engine around, I would have had to relocate many things.
I ended up putting shorties in it and they fit. The problem I had was the header down tube (early and late years) would interfer greatly with the motor mount tower (original one to truck).

My point is this, I think this transition year may have some unique shock towers to fit the 351m/400 in the highboys and if the headers are not made for them, they may or may not fit. Make sure that the mfg will take back the header if it doesn't fit. Get the name of the person you talk to and talk to the same person each time you call. It will help if you have to return it. Make sure they understand that this is a transition year and ask them if it will fit. If they just want you to "try it and see", ask them if they will pay for shipping to return it if the header doesn't fit.

Best thing to do is keep doing what you are doing and ask questions and find someone who has headers on a 351m/400 highboy. Then you will know for sure that the header fits.

Good luck.

 

thanks, thats good advice