Those SS/GT motors are pretty high maintenance too. A friend runs one...pistons w/ only one compression ring. Requires freshen ups every 50-60 passes. His "factory unported" cast iron heads cost over $7,000 a set.
7" torque converters, not to mention a trick Quadrajet.
Comparing a typical low maintenance bracket motor to what these SS/GT motors run, well, it's just not a good comparison.

CHIP
'70 hemicuda, 575" Hemi, 727, Dana 60
'69 road runner, 440-6, 18 spline 4 speed, Dana 60
'71 Demon, 340, low gear 904, 8.75
'73 Chrysler New Yorker, 440, 727, 8.75
'90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt
'06 GMC 2500HD LBZ Duramax