Join Date: Jan 2001
Location: Lubbock, TX USA
Re: WTF is a Tall Black???
Deck height is the distance from the crank centerline to the deck of the block (where the heads bolt on). A passenger/standard block measures 9.8" (9.780" if you zero deck it) and a tall deck is 10.2" (10.180" at zero deck). Tall deck blocks are all 4-bolt mains. They were developed to accommodate the 4-ring piston that was run in truck engines. I understand the thought was that since truck and industrial stuff is generally loaded harder than passenger engines, they needed the extra ring for durability.
At any rate, stick with passenger deck blocks unless you're forced to the tall deck stuff. There are a lot more selections for rods, pistons, intakes, etc. for the 9.8 configuration than 10.2
FCS Harmony Racing
Momma always told me not to look into the eyes of the sun.
"But momma, that's where the fun is!"