im sure this question (or similar) has been posted a ton of times...
and i did search for similar topics but didnt really find an answer to my question..

what kind of power capabilities does a "mostly" stock LB9 or L98
with a single turbo application??
"mostlystock...like upgraded injectors, ported plenum and intake, and other minor things.."????

(with like a medium turbo...20G or t3/t4 or t4..)

 

Thats a pretty vague question, but if you don't mind pushing the limits of the stock bottom end I think 450 flywheel horsepower is not out of the question. The problem is that a turbo doesn't solve the low-rpm nature of the TPI system. You can still make a lot more power with the turbo, but your powerband will still fall quickly above 5,000-5,500 rpm (this makes it hard to achieve stunning HP numbers because HP is a function of RPM). For instance, my TT 89 IROC L98 put 327hp @ 4200rpm and 468ft lbs @ 3400rpm to the wheels at 6psi of boost (this was on a hot day and on a chassis dyno- not much cooling air for the intercoolers). It's a low RPM torque monster, but still suffers at the upper end. Granted, the turbos on at that time were two very small junk-yard Volvo T3s (45 trim), so they weren't helping extend the power-band either (they're restrictive over 5k rpm- However, it now has two T04E 57's on it!).

Hope that answers your question.