So I just bought a 2015 Silverado 2500HD and I am looking to put a 3-5" lift on it. With 33's or 35' on it. Now i would like to make the engine to be more powerful but also more efficient. Now I am no engine expert so I am hoping someone can give me some good tips.

 

Not really possible to have both. Just have to drive slower and keep off the gas. We used to run a vacuum gauge on the dash. Higher vacuum less gas.

 

Ok. Well what could I do to just get more horsepower then? What could i do under the hood to just get some more horsepower?

 

Assuming you won't have to pass any smog laws, the sky is the limit, but I'll assume you don't mean something like a Supercharger or Nixrous Oxide. Those will get you some serious HP, but Nox can melt the pistons too. High flow heads would be a good way to get more HP. Opening up the exhaust would be a good start too. Camshaft upgrades are classic. If you are serious about power, https://www.bankspowerproducts.com/ seems to have some serious HP upgrades. Of course its not cheap at all. Looks like one of the sponsors of this forum has lots of upgrades too: https://truckprousa.com/c-167894-per...rivetrain.html