Duramax VVT Science

An Inside Look at the Ht Turbo Promax 64

- JS Hansen

The introduction of the Variable Vane Turbocharger (VVT) on the LLY GM Duramax in 2004 may have been mostly emissions control related, but in the years since, it has proven to be a solid performer with great power potential with a few tweaks from the aftermarket. The Garrett VVT used on the 2004.5-2016 Duramax has gone through a few revisions with each engine platform, but remains a pretty solid turbocharger for daily driving, towing and power output up to around 530 horsepower.

But as with anything else, the aftermarket always finds ways to improve performance and the VVT turbo is no different. High Tech Turbo of Salt Lake City has specialized in everything turbo since 1985 and has been modifying the OEM Duramax turbochargers for quite a few years with great success. The ProMax 64 will support up to 600 rear-wheel horsepower and can reduce exhaust back pressure and EGTs for daily driving and towing applications. It also bolts directly in place of the stock unit, with no other changes necessary.