Beyond a certain point, efficiency is the issue. A high end convertor is a custom peice from shell to stater to fins etc...it will go when you dip the throttle like stock, it will not drag rough idling engine down at idle in gear.
The lower priced, cut fin converters allow slippage, and can in a maxed out stall version create a ton of heat below the stall/full lock up. Average hot rod 2600-2800 is fine, some do fine with 2400 and work great.
It's like hedman vs tti...
Both are upgrades...but one is better and does not have negative by products like ground clearance, too small for max power.
But I'd take hedmans over stock 318 manifolds. I'd take a cut high stall over a stock stall any day.
Converter shows like... off idle slip, under stall speed is slippy.
Example
.. If it stalls to 2600 rpm ...you will see the off idle flash 'under normal operating pedal' will rev the tach 1400-1600 rpm.
