Would not of guessed this tidbit....
Us, either.
It's always been my understanding that 3FE manifolds are late 2F head compatible, and they may be, I dunno. Based on that information, would've assumed 3FE down pipe would work, yet not even the flanges do.
Another interesting tidbit, is the difference in the 3F manifold ports, compared to the late 2F head, which is said to be the same as 3F. The limitations of port matching were constrained by the 3F inlets/outlets, because of the size disparity.
What'd this gain?
Probably 1/32 HP, but it may prove valuable knowledge in coming years, if late US 2F manifolds fatigue like earlier F/2F, since the 3F manifolds and carbs are readily available, the carb costing new about double rebuild of a 2F.
2F diaphragms are now NLA, so might be viable options for 60 crowd intent on keeping the 2F.
3F heads, albeit in OE form are spec'd for lower octane fuel, with differences in combustion chamber and non-hardened valve seats, are available, too.
All that and.....I've not had the best experience with aftermarket exhausts, be them high quality (translated-$$$$) pre-fabbed, custom or ma and pa shop built on anything from domestics, diesels, quads, 80 series. They've all prematurely failed of failed to deliver.
Realize there's little choice from either the downpipe back, mebbe even the y pipe back, remains to be seen, but directives given will be "quality and quiet".
So, all the above was prolly unnecessary, I realize.
I was snickering thinking about your snickering, and took no offense, since I do deserve it.
Don't recall the thread, but was lambasted not too long ago with similar sentiment, and there's little to offer in defense......except:
Fully intend to DD this Pig, sharing duty with an 80 I picked up a couple of months back.
While I'll probably have more than a newer model between the both (maybe two new ...) but it's worth it knowing many, many years of service can be expected.
No one seems to understand, not family, friends, or acquaintances.
One instance, was questioned about the 80 by a high school acquaintance, now dad on my son's team. He'd asked about 80 and where the FJC was, and could not believe that I'd prefer this over the newer, or that I would sell the newer.
Another, it trickled back that I must be having financial problems, same reason as above, and I'd mentioned my elation to a buddy that Mrs. D has asked why she wasn't driving an LC (it just pisses her off when I try to explain that, essentially, her GX IS an LC) and the she preferred the 100 over the 200.
I was ecstatic, having nothing to do with the cost disparity, but guess that wasn't what the buddy took out if it and sure wasn't what whomever he'd talk to interpreted.
Not that I give two chits, 'cause I don't, but of all places on the face of this planet, I'd think you all would understand, at least, the joy of DDing a Pig, as well the sense of accomplishment, responsibility and pride that comes with (what normal folks may see as undeserving) perpetuating this rare, odd beast, however the form evolves.