A blurb from a web site I was reading…

A stock 429 Twisted Hemi has stock specs of 4.36 bore x 3.78 stroke. Last year’s 440-inch 429 was derived with a .060-inch overbore and a .1-inch offset grinding of the crank’sthrows. The 480-inch stump-puller comes from the deft use of a .040-inch overbore (thus preserving cylinder wall strength for potential nitro-induced detonation) and the use of a 460 Lincoln crank. The Lincoln 460 crank was also re-ground off center, thus yielding a slight stroke advantage over a “normal” 460 Lincoln crank. The 480’s dimensions are: 4.040-inch bore x 4.00 stroke (*Webmaster Note, yes yes, I know, that would be 410 cubes, not 480. Must have been a misprint). The cast Lincoln crank has been tuftrided and blueprinted; the entire Lincoln/stroker idea was Wayne Gapp’s.

Wayne Gapp, a former design engineer for Ford Motor Co., previously helped the Carmel team and continues to assemble their basic shortblocks. Gapp’s 429 prowess — he campaigns a Boss 429 Pro Stocker! — is evident. He is responsible for the full Hemi chambers on the Vindicator’s engine and for “re-designed” ports on his and Jack Roush’s Gapp-Roush Pro Stocker. The full Hemi chambers (he cuts away the protruding edges of the Twisted Hemi chamber) are good for two-tenths on his carbureted Pro Maverick. Much of the machine work for the Wiscomes is performed by Bill’s Speed Shop — Bill Coons in Detroit, Mi., under the auspices of Gapp-Roush.

Hmmm…