Power gain in a stock motor vehicle - especially nowadays, given the high state of tune and electronic control - is an elusive goal. Most of the time we're looking at 2, 3, 4 hp here and there so it takes quite a bit of test & tune to get meaningful, safe, reliable modifications done. Most modern vehicle tuners are also hampered by the EPA and local emissions requirements as well as the lack of aftermarket parts support due to low or no demand. One of our CF members did a full-mod turbo install in a 1999 STS Northstar - did some staggeringly impressive trap times - played with it for a while, detuned it for the street and sold it. After sinking over $18,500 into the work - so it
can be done, but it's nowhere near plug & play............. You must test
after each mod to see whether you have improved or gone backwards - install several new toys at the same time and you have no idea which ones helped or hurt.
You might get in touch with one of our tuner CF members - TwinTurboFan or TapOutTuning (?) comes to mind - and ask a few questions before you begin. I was a big block and SBC builder so the newer V6 and turbo stuff is not high on my knowledge list.
Here's one of my Olds 455 marine conversion builds - many tricks - (I love me pics) -
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