Just scored a Super Six and matching trans
The slant six was originally a 170 cubic inch motor
Nope. The 170 and the 225 were designed side-by-side, from the very start. The engine size was not "increased" to 225. The valve sizes were considered ample for the 170 and adequate for the 225 in their intended applications. See if you can get hold of (many-decade Chrysler head engine engineer) Bill Weertman's 3-volume "History of Chrysler Corporation's Slant-Six Engine" from Chrysler Historical, or pick up Weertman's awesome
Chrysler Engines 1922-1998 book.
There was a weak-kneed (try and find one) offering that put the Hyper Pack manifold,cam, and a few other parts on the 225, but VERY few ever saw the light of day
Er
that's wrong, too. There was nothing "weak-kneed" about the Hyper-Pak; go read any/every road test of cars so equipped, and the accounts of how eight Hyper-Pak Valiants came in 1st through 8th in the NASCAR compact car races of '60 and '61 (and there weren't any after that because it wasn't much of a competition with the Hyper-Pak Mopars so completely stomping all other comers). Moreover, the Hyper-Pak kit was a good bit more complete than you seem to understand (going by your "a few parts" comment).
Sure, the stock head isn't conducive to massive airflow, but it's hardly the can't-get-around-it obstacle you seem to think it is. Those NASCAR Hyper-Pak Valiants were wound up to over 7,000 RPM
y'don't (can't) do that if the head's so irretrievably in the way. A carefully-chosen slant-6 head has a lot of room for porting and bigger valves. There's pretty constant chatter about wouldn't-it-be-nice-to-have-a-new-slant-6-head, and maybe it'll happen sooner or later, but consensus so far amongst those with fast slant-6 cars is that the head is not in the way as much as you seem to think it is.
and the /6 remained a poor-breathing, station wagon motor throughout its life.
Mmmm...no, not so much. The Australians and South Africans who bought factory high-perf 2bbl and 4bbl versions of it starting in '67 might disagree with you. As might the Argentinians who put their local larger "906" slant-6 blocks to good use and devised such droolworthy items as
this 24v head.
There ARE some impressive /6-powered cars out there.
We agree.
But, no matter how they tweak these unblown engines, the small ports and smallish valves (even the bigger, aftermarket ones) make it a real uphill battle to get enough airflow through that head for specific output much over the 1.2 horsepower per cubic inch range.
I dunno, maybe. I tend to think in E.T. numbers rather than horsepower numbers. There've been some pretty impressive E.T.s from slant-6 cars without forced induction, as it seems.
And, to get into that territory, you need an engine that is so radical that it's not very driveable on a daily basis.
True enough
A slant six engine has an unbelieveably strong "constitution."
Yup.