I have 2003 TB LT (I6 4.2L)... I was curious on what are some good cams to put in or just some more HP ideas .. let me know what I can do to make this thang scat 😈💨


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There are some Pricey Engine Re-Build components such as expensive H-Beam Con-Rods... but because the GM Atlas 4.2L sports a 24 Valve DOHC Engine Head and Valve Train using the VVT (Variable Valve Timing) feature between 0-25 Degree on the Exhaust Bank... there are NO After-Market Cams or Forged Crankshafts that are available as "Drop-In Parts" like those available for most LS V8 Motors. Your best bet is to view the information via THIS Link... and afterwards, enjoy driving your relatively Stock I-6 Powered SUV after having @limequat run a $99.00 "Tune" on it for you:

...there ARE only a Handful of YouTube Hot-Rodders that have Monkeyed the Horse Power Out of this Straight Six Motor to the "Tune" of nearly 500 Horse Power... but they have employed Hard to Build Turbo-Charging Rigs in Non-GMT360 Vehicles (Checker Cabs and Studebaker Larks) and doing THAT only after investing a Boat Load of $$$ and a HUGE Trial and Error Effort in order to accomplish this Daunting Feat.

"Subdue Your Appetites... and You've Conquered Human Nature..."
From Charles Dickens'... "Nicholas Nickleby"
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Thread Starter
Need help on finding some (step up from stock cams) cams that will maker her lope lol ..
2003 LT 4.2L
Need opinions on how to boost my HP and top speed?🧐🤔
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Master Blaster
A search throughout the site will yield quite a bit of info regarding turbos, injectors and Youtubers that have done a few things with this engine. But as @MRRSM has said, there are practically no off-the-shelf performance parts for it, not even head bolts or studs.

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