340 4 barrel and 340 6 barrel: were they really UNDERrated?

i never drag raced anything other than a couple of stop light drags
but looked up the time my 2001 audi s4 should run seen #s 13.01 to 13.50 at around 102
other then all wheel drive 6spd its only rated at 250hp
my 86 vette rated at the same 250 hp runs 16s 103 seems slow but nothing run good in 86 ...and even though i had the vette up to 152mph the audi has more pull at over 100
so my stock build 69 dart 340 4 spd should give the audi a run