Mad Dog 67-72 Big Block 4x4 headers

[i82much]

I've been looking for a set of full length headers for my 72 K10 that has been converted to a 396 with exhaust manifolds. I've found a few posts by people that have managed to make headers for other applications work, and I'm aware of the shorty and Sanderson options, but I couldn't find a full-length header that was specifically built for 67-72 big block 4x4 conversions.

I contacted Mad Dog since they actually list a header for this specific application on their site and they confirmed that the headers are specifically designed to fit 67-72 big block 4x4s.

Has anyone tried these? I'm surprised I haven't read more about them. Seems like pretty good news for a lot of us!

[BASE]

Everything I'm seeing on their site says it's fenderwell exit. Is that what you are wanting?

[i82much]

Originally Posted by BASE

Everything I'm seeing on their site says it's fenderwell exit. Is that what you are wanting?

I dunno, is that impractical for street use? I haven't really ever seen a set of fenderwell headers before. From the pics it doesn't look too crazy but I could be wrong ...

[Richard]

Was going to mention the fenderwell exit myself. As long as running the exhaust outside the frame fits your needs and trimming inner fender well to fit is okay with you, they should do the job. Custom parts. Really need to be looking for that particular type of header, that is probably why you, myself and most others have not really heard of them.

[i82much]

Originally Posted by Richard

Was going to mention the fenderwell exit myself. As long as running the exhaust outside the frame fits your needs and trimming inner fender well to fit is okay with you, they should do the job. Custom parts. Really need to be looking for that particular type of header, that is probably why you, myself and most others have not really heard of them.

thank you. looks like maybe stan’s makes a tri-y that fits nicely? have to see what they say. i read that doug’s makes a tri-y but requires some trimming of the frame, i would probably just keep my manifolds before i did that.

[Richard]

Originally Posted by i82much

thank you. looks like maybe stan’s makes a tri-y that fits nicely? have to see what they say. i read that doug’s makes a tri-y but requires some trimming of the frame, i would probably just keep my manifolds before i did that.

Used Doug Thourley 1 7/8" mid length tri-y headers on my truck. 6.2 LS swap though. Did require minor trim of upper frame rail. Pretty sure there are pics in my build thread. Posted better pics here https://67-72chevytrucks.com/vboard/...2&postcount=13 in another thread.

[i82much]

Originally Posted by Richard

Used Doug Thourley 1 7/8" mid length tri-y headers on my truck. 6.2 LS swap though. Did require minor trim of upper frame rail. Pretty sure there are pics in my build thread. Posted better pics here https://67-72chevytrucks.com/vboard/...2&postcount=13 in another thread.

thanks for the info. looks like stan has retired, so going to have to either do some trimming or just keep the manifolds for now.

[BASE]

I'm in the same boat and it's frustrating. I've spent hours reading through old threads. I considered the fenderwell exit type briefly. I don't think I want to have to cut out the inner fender, or have exposed pipes in the wheel well.

I'm probably going to resign to having to try several and get bent over shipping them back when they don't work. Or build some myself, but that looks like a lot of work. I guess there are a lot of variables when swapping a BB into an older truck (4WD/2WD, fwd/aft holes on the frame, manual z-bar or not). It may be easier to get the headers and put the engine where the pipes will fit.

[mattshea125]

I went back and forth on headers with my 4x4 big block project. After beating my head against the wall I went with factory 1970 GM Chevelle SS 454 manifolds for a few reasons....
-Super tight to the block and have no problem clearing the frame rails
-2.5 inch 3 stud flanges so you can use factory hardware and donut gaskets
-More than enough flow to support over 400 HP
-They don't leak and loosen up like headers causing embarrassing noises
-Enables you to use the factory plug wire heat shields so burning plug wires isn't an issue anymore

[BASE]

I'm still going round and round with it. I hear you on the header woes. Every set I've had were a bit of a PITA. I built this current 496 to make power at 6500 and spent some $ doing it. Probably not warranted for what it's going in, but it's done now.

The hooker super comp (2817) coated ones look nice and sounds like they should/maybe fit fine. $1k is a hard to swallow though

There are a few sets of hedmans that look like they might work (69110, 69130). Look to be lighter weight and on the cheaper end of the spectrum. Seems some have got them to work on square bodies.

Hooker 2463's are what I'm looking at the hardest. Pretty reasonably priced. I think I'll probably end up going with these. I have to weld in some O2 bungs so painted is probably best considering that. Maybe have them coated if they fit.