'72 Big Block k20 Headers - Need better fitting headers

[nitrosport_5]

Hey guys, Just getting my truck tore down to replace the cab and looking at the headers, I dont know if they are the correct size for the engine/truck, or if they were just a random set of headers shoe-horned in there. Also, I was told by the previous owner that the engine was moved an inch back, or forward, or upside down... i dont remember . Is this somthing that would have been done to put a big block in a 4x4? I should have gotten pictures of how far the engine is from the firewall but didnt think of that until i was back at home.

Here are the pictures of the header fit. The engine is a 396 and someome has carved the frame to fit the headers. Not sure what headers they are, but is there any other headers that may fit better? Thanks in advance.

[Bishops Trucks]

I have a used set. I'll have to dig them out and get you a couple pics. They were in my '71 K10 bolted to a 396. My frame was never cut for clearance, maybe these will work for you.

[nitrosport_5]

yes please let me know! if they are in good shape I'd be interested in purchasing them if you wanted to get rid of em

[ZombieWeinerDog]

I use these: http://www.summitracing.com/parts/ho...1hkr/overview/

[nitrosport_5]

Originally Posted by ZombieWeinerDog

I use these: http://www.summitracing.com/parts/ho...1hkr/overview/

on a BBC 4x4 with no frame contact issues?

[ZombieWeinerDog]

Originally Posted by nitrosport_5

on a BBC 4x4 with no frame contact issues?

not a 4x4, but they fit well, sit a little lower than i wanted, and i had to modify my gmc pauls crossmember, but it wasn't hard.

[k5kev]

I have a 72 K20 Suburban that I put a 502 in, and tried 5 or 6 different headers for fitment. The only set that fit right was Hooker 2463. These have 1-3/4" primaries and 3" collector. Hooker 2817 looks to be the same exact headers, just with 1-7/8 primaries, but I never purchased and tried.

More than likely the previous owner moved the engine forward, as this helps and is typically needed to clearance the firewall to the big block valve covers and HEI distributer (if used). I moved my engine forward about an inch and still had to put a small dent in the firewall to clear the driver side valve cover.

[nitrosport_5]

thanks k5kev. that makes sense. I do have an hei setup on it currently.

[nitrosport_5]

I think I'll pick up a set of the 2463s. so since the engine is an inch forward, should the headers fit different than if it was back an inch? just trying to figure out why my frame needed trimmed. must have just been incorrect headers?

[nitrosport_5]

Originally Posted by k5kev

I have a 72 K20 Suburban that I put a 502 in, and tried 5 or 6 different headers for fitment. The only set that fit right was Hooker 2463. These have 1-3/4" primaries and 3" collector. Hooker 2817 looks to be the same exact headers, just with 1-7/8 primaries, but I never purchased and tried.

More than likely the previous owner moved the engine forward, as this helps and is typically needed to clearance the firewall to the big block valve covers and HEI distributer (if used). I moved my engine forward about an inch and still had to put a small dent in the firewall to clear the driver side valve cover.

k5kev, thank you for the header recomendation. THese fit 100x better than the headers that were on the truck. now i just need to figure out how to go about fixing repariring the frame. I do have one question about your header install.

My driver side header collector sits lower than the passenger side, and the passenger side header is just barely clearing my transmission bolt. Is yours the same way, or did i get a bad set? thanks!

Dont worry, im not leaving the wires dangling on the header. Im currently ripping apart the entire truck to a bare frame, so everything is being removed. just wanted to testfit the headers before i installed the engine!