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OH, Doc....

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Evidently, the stocker flows pretty well. There are tuning advantages to changing the length of ALL the pipes for a given RPM/working range. There are some formulas around that you can calculate the correct length/diameter from the end of carb bellmouths, to the valve seats, and from valve seat to collector. Somewhere I have a book on engine tuning from the late 50s early 60s that delves into all of that. The stock "early" cast iron manifold is pretty closely matched to the engine, even if somewhat tuned. The "special tuning" handbooks have a lot of data also. Matching the ports to the manifold and all that helps too.I used to leave a slight "lip" at the exhaust port to manifold joint to take advantage of a little "anti reversionary" effect. My point was that to be most effective, a header has to have a "long center branch" to work best with siamesed exhaust ports. The same theory holds true with sprigets.When I was young and dumb(er) I had a 67 sprite that I had a gen- u- ine special tuning header and megaphone exhaust fitted to. It was LOUD when it was "on the pipe" but it was pretty quick too. It was great when you could stroll into the dealer and just buy stuff like that over the counter.
 
Peco doesn't make a bad system and it has all of the design characteristics that compensate for the terrible head design.

And it won't cost as much as a custom designed & dyno'ed one which can become quite expensive :eeek:

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Never met a Peco wot DIDN'T need whackin' on to fit. :madder:
 
We're an eclectic group. :laugh:
 
& we did it politely without getting political! Or in religious arguments!
 
Perhapses I should say Peco <span style="color: #FF0000">style</span>...

As in.....

2 into one / 22 1/2" (1 3/8- 1 1/2") primary pipes and 2 into one 2" muffler pipe.

Good for the standard (performance) Moss cam.
 
Tony, I once had one of those headers. The collector hung VERY low and it started to rust out at the collector as well. I later cut it up to rework it and make it work a little better. It now looks a bit more Peco-like.
 
Jeff - both of mine are solid & in great condition except the one where somebody changed it to a slip-on fitting...I might just take it to the muffler shop to have them retrofit it to original..I have the other as an example.
 
PM me with what it'll take to pry it from your grasp, Colonel. Unmodified would be fine. I have a collector here to use as pattern. :devilgrin:
 
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