are sb 427's really 427 c.i.'s

[Streetwize]

With respect....I think I know a pretty good amount about most of the heads that are out there, and I know a better than average amount about BIG BIG BLOCKS (ex: I run Chapman CNC'ed 380+ heads on a 700+hp 517" street car) ....but with big blocks proportionally big cross section ports will want either (big cubes to make torque) or Lots of RPM to make the ports work. The really trick "go fast" stuff for big blocks all have farily large (to really large) port cross-sections as they are designed primarily to work with todays modern BIG (typically 480+ cube) Big blocks. The really big stuff flows 465+ cfm and state of the art pro stock 500" stuff is well over 500.

If you build a 427" FE and a 427" 9.2 to 9.5" deck height smallblock with similar head flows (take your pick as long as you go Apples to Apples) compression, cams, induction and exhaust, I'd put my $$$ on the small block making more power, and fromthe driver's seat the smallblock (by virtue of a more efficient port (smaller valve, longer stroke, better port angle and smaller port cross section) it would make more torque out of the basement and then up top by virtue of a MUCH LIGHTER bobweight and valvetrain mass will rev faster and higher and make more power up top. Maybe not much more, but definately measureably more. So I think you can attain both more peak power and better average torque through out the powerband, so at 427" I think the "Nothing kicks like a big block" doesn't really hold up any more.

Remember....To compare fairly you have to build both to the same size and parameters. A smallblock reaches a practical limit at around 450-460 cubes, (4.155 x 4.17-ish), but even potentially bigger with a 400M deck block. compare that to maybe 410 only 10 yrs ago. Beyond that you are pretty much in the Big block realm.

The topic is 427 cubes (and ONLY 427 cubes).....7000 cc's.......for Fords (my .02 cents) the best power packages at that displacement or below are small blocks in terms of average torque and Hp per cube. Again....It's primarily due to the tens of millions of dollars invested over the years in NASCAR small block (358") technology that has trickled down to the hot hodding world.