What's the difference? Tigé GM Vortec 5.7L multiport EFI

[Miss Zog]

While we are on the subject and it is my second post.

Curious what the difference is between these three power plants. The displacement is the same for all three so what are they doing to increase the HP. Is it electronics, components, ect? I pulled this from the 2008 powerplant choices.

Tigé GM Vortec 5.7L multiport EFI — 320 HP
Tigé GM Vortec 5.7L multiport EFI — 340 HP
Tigé GM Vortec 5.7L multiport EFI — 360 HP

Cheers,
Miss Zog.

[turbonine]

More agressive cams are one of the hardware differences.

[chpthril]

Along with a different cam profile, they can change the spark curve (timing advance) and in injector "on time" (air/fuel mixture)

[mtnsmith]

The 320 is the standard, the 340 has aluminum risers that allow the engine to breathe easier, resulting in a small hp gain, the 360 is the HO-high output, version. I am not sure what else the HO has that the 340 doesn't, but I'm sure cam and intake might come into play. That's what I've been told atleast

[FIC]

The 320 hp has cast iron manifolds, the 340hp has better flowing aluminum manifolds and calibrations, the 360 hp has roller rockers with different ratios and calibrations , this is what MP indicated.