New Headers for D/S AMX

[Jeff Lee]

Forum member Garrett Monde who also runs a D/S '70 AMX just completed this beautiful set of stainless headers for me. Job was completed on time with plenty of interaction between him and I as he lives in Connecticut and I live in Arizona. He did an excellent job in conforming the primary tubes to the dog-leg exhaust port. Also the primary tubes do not nose dive out of the ports like typical shelf headers. Still waiting on lifters so we can get the engine together for final assembly.
Collectors are from Burns and yes, the pan evac will be capped or removed. That was from the SuperStock engine.
Headers are ready to ship. Check them out!

[bigsixman]

That appears to be a well made set of headers for your AMX. Let us know how they work out when you get it up and running.

[rallye bob]

Jeff;
Could you share primary tube sizes (steps)? TIA

[Jeff Lee]

1 3/4" to 1 7/8"
28" length"

[Patric Fox]

NICE!! Do you expect a performance gain?

[gmonde]

once jeff get s his on the dyno his intent is to test a few different sets , my design off the head has the exact profile of the dog leg port,, i think there is hp just in that area ,,yes it certainly takes more time but i think its well worth it ,,,in the off season if time allows i will be doing some testing as well gmonde

[Jeff Lee]

Originally Posted by Patric Fox

NICE!! Do you expect a performance gain?

As Garrett mentioned, I have access to a set of 1 7/8" Hedmans, 2" Hookers, my old REF's (same tube size as the new Monde Headers) and then of course the new ones. As long as I can get them all to fit the dyno, I'll give them a try.

I've always thought a swoopy header was the way to go and I see that Mark @ Performance Welding seems to have the same theory. From what I've seen of Marks work, he also builds a nice header.

My older engines were dyno'd with Jeep fenderwell headers as that was all that would fit on the antique Stuska dyno frame we use. The $79 1 3/4" fenderwells made surprisingly good HP.
Then we built some exhaust flange adapters about 3" wide so the REF chassis headers would clear the dyno frame and it still made good power. Hopefully, these new headers will clear the dyno frame. Unfortunately, the adapters will most likely be needed on the other headers.

In my discussions with Garrett I stated I thought something short of fenderwell headers would be best and I saw his work on his own headers and was very much impressed that he came up with a forming tool to replicate that dog-leg in the primary header tubes to a level I've not seen in an AMC header. My custom REF headers were good at the port, just not this good. And I had Ed headers before the REF's and they had an OK port but again, not as good as the REF's. And I'm sure you know the store bought shelf headers look like somebody crammed a round pipe into a dog-leg flange and beat it in and filled the rest with a stick welder.

Here is what I'm talking about with Garrett's work:



Contact Garrett here with a PM and see if he can build a set for the narrower engine bay of the pre-1970 AMC's using a local car. I'm sure he can find one. You know, they're everywhere, just like Camaro's with one on every corner!

[Glenn Hayes]

WOW! Those are a work of art.