Tag Archives: VVT

Still looking for improved performance for the Sprint-T

I have been looking at the various engines available on a cost/performance basis, and the Gen IV architecture LS family is starting to look better and better. The Gen IV engines come with things like DOD (bad) and VVT (good) to balance performance and fuel economy. I’m looking at the prices for the aluminum 5.3 L engines with VVT that came in trucks and SUVs. They are trending slowly down to something I can afford to pay after getting removed from the vehicle, the oldest being 12 years old now.

The reason I want the VVT is it gives me the benefit of a wide powerband. How camshaft timing affects engine performance and from Richard Holdener Tested-SBC adjustable cam timing. Basically VVT lets the engine controller adjust the cam timing on the fly, with the cam advanced below torque peak, and letting the cam retard as RPM increases to increase upper RPM power. Basically this lets a small cam (short duration) act like a big cam (long duration) at high RPM while retaining the small cam goodness down low. It’s not exactly like a bigger cam, but it makes the small cam better. Since what I’m looking at is making the powerband as wide as possible VVT is what I want. I can advance or retard the cam as needed depending on RPM. I can adjust the cam events to the best time for the rotational speed of the engine.

And I watched the NASCAR Cup race from ‘Dega today, and there were fewer wrecks and the wrecks were smaller than in previous years. Aaannnnnd, congratulations to Brad Keselowski, they had the 9th different winner in 10 races, the playoffs are going to be LIT this year, and the race for the cutoff is going to be cutthroat.