how much boost on stock lq9
There are a TON of variables as to why a certain amount of boost doesn't mean a certain amount of power.
I've seen people run upwards of 30 psi on a stock bottom end and run 8.80s in the quarter. At the same time, stock48 is running 22 psi or so on a 76mm turbo and running in the low-mid 8s on a stock bottom end. There is no magic number.
A tiny turbo forcing air through unported heads on a stock cam and intake with no intercooler might make 600 HP at 23 PSI and ~5600 rpm and the block live forever. Take the same bottom end, put on ported LS3 heads, a Holley Hi-Ram, a custom grind turbo cam, A2W Intercooler, methanol, and a large billet 88mm, and the bottom end blows apart at 18 PSI at 6400 RPM.
There are literally 50 people a week that ask this same question.
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