I used to refer to the same quote as Jeff does, until I looked at an original 194 cubic inch 1929 Stove Bolt Six (Cast-Iron Wonder) engine at the 2006 National ATHS show in Baltimore. The head bolts are not slotted pan head 1/4" diameter x 20-thread machine bolts (stove bolts).
Look at this page from "Cast Iron Wonder" by Doug Bell, 1953 , published by the well-respected Floyd Clymer (who also wrote the forward to the book).
The exterior bolts/machine-screws were not 1/4"-20,
slotted head-bolts; they were 1/4"-20,
slotted-head bolts holding many sheet metal parts (and other parts) to the block and the head. This caused jokers to say the engine was held together with stove bolts - it was a
stove bolt six engine.
I think that mistaken notion that the head bolts were 1/2'-20 stove bolts was made long ago by people who mis-read the description
slotted head bolts.
Tim
