"Iron 225 blocks can safely take a 0.060-inch overbore"
…iron blocks can safely take a whole hell of a lot more than a 0.060" overbore, assuming you measure/check first (which is good policy no matter what overbore you're planning).
"but the integrally-cast iron bore liners limit the aluminum block to 0.020 inches over"
0.040" is the correct figure for the max overbore on the aluminum 225.
"Beware of cast-iron post-1976 cranks. They’re strong but have non-interchangeable narrower bearing surfaces which make 1977-up 225s a breed unto themselves."
The forged/cast crank split took place in the middle of 1976 production. It was not up-to-'76/post-'76.
"ARP offers specially designed stud kits designed to work with the softer aluminum/copper/silicon alloy block material needed to facilitate the 10,000psi injection-molded manufacturing process."
Sloppy writing. Words picked to fill space rather than inform. Just say ARP has head studs compatible with the aluminum engine and be done with it. The aluminum blocks were die-cast, not "injection-molded".
"The aluminum 225 accepts the same wide-bearing crank, rods, and bearings as any pre-1977 225"
Nope. Some 1976 225s will not accept those parts.
"With their flat tops, these cast pistons duplicate the stock 8.4:1 compression ratio. Safe for general street performance use, the lighter cast aluminum construction helps reduce reciprocating mass for improved efficiency and throttle response."
More babblety-babble to fill space rather than inform. The completely ordinary 0.020"-over stock-type pistons are lighter than...what? Lighter than cast iron pistons that were not used in any Slant-6 engine in the history of ever, because cast iron pistons went out of style with the Jitterbug and Prohibition?
"The Slant-Six head can safely withstand a 0.100 thousandths deck cut."
Sloppy writing with a dumb error: It's "100 thousandths" or "0.100", not "0.100 thousandths", which normal people pronounce "one ten-thousandth" or 0.0001.
"This reduces chamber volume from 54 to 44cc and bumps compression from 8.4 to 9.2:1 with stock flat-top pistons"
Don't bet money on it! There's a ton of variation in combustion chamber volume and SCR in production Slant-6 engines. There is no single amount of milling that will deliver a certain CC volume or compression ratio. Those might be the numbers they measured (if they bothered measuring) on their particular head, but that doesn't mean squat for any other head.
"At 59.2 pounds, the 225 head (bare)"
The particular casting they were using, maybe. There are multiple different interchangeable Slant-6 heads, that weigh differently. Also, there is nothing such as "the 225 head". Slant-6 head differences are by year, not by displacement.
"The pen points out the old-school one-piece Chrysler solid lifters which have been replaced (industry wide) by taller multi-piece solid (and hydraulic) lifters."
Umwhut? The factory used both straight-side and barbell-type solid lifters as standard equipment in the Slant-6, depending on production date. They are fully interchangeable in every way, including height. Mentioning hydraulic lifters here only adds confusion; there were hydro-lifter Slant-6s and a solid-lifter engine can be converted, but that's nothing to do with the engine they built and it takes more than throwing in a set of hydro lifters.
"Lash is set at 0.010-/ 0.020-inch cold."
Hot.
"The surprise was how the engine idled smoothly without any bogs or hiccups under load despite the carburetor’s miniscule 1.42 square-inch venturi area."
The
real surprise was how clear the radio in the car sounded, without any static or station fade at highway speeds despite the red color and juicy deliciousness of the raspberries we bought at Safeway. Since we're talking about things that don't have anything to do with each other. Small carburetors are really good at providing smooth idle and lack of bog.
Taking a break from the text for a minute: those aren't Dutra Duals they installed, they're Dual Dutra Duals. The two setups are not alike. Since we're on the topic:
"Dutra Duals http://www.dutraduals.org"
Nope, no such website. Never has been.
"the new two-piece Dutra Dual cast-iron exhaust header"
Did somebody set the Wayback Machine to 1985 while I wasn't looking? Because Dutra Duals (including the front casting, two of which are used to create the Dual Dutra Duals setup) have been available since sometime in the mid-late '80s. They're keen and excellent, but they're not new.
