VTT Is proud to introduce the GC and GC+ line of turbochargers for the DAZA, and DNWA 2.5L Audi engines.
These units are a white sheet design based around the factory turbocharger footprint while removing all the factory restrictions left when people stuff larger wheels into factory housings., AKA “Hybrid” These turbos are priced outright meaning no core charges. Keep your factory turbo in case you ever need to go back to stock, sell it to recoup some of your investment, etc. This also means no downtime, once we have the units on the shelf, you order -> We ship…
We start with our investment cast 310SS turbine housing/manifold with improved runner design for better velocity and flow. We couple this with a turbine housing AR increase from .65 on the OE housing to .85 on the VTT housing this will allow much more flow before reaching the backpressure limit while keeping good response. Following the factory footprint allows any existing downpipes on the market for factory turbo to be retained.
Next is the Compressor housing. Custom cast with the factory footprint but we do away with the 2 bolt inlet, and have a simplified 3” barbed inlet coupled with our 3-4” reinforced silicone turbo inlet that will mate with any 4” inlet on the market. Following the factory footprint also allows the turbo to accept our silicone reinforced charge pipes or any already available hot side charge pipe options. Boost control options are 1. Reusing the factory vacuum actuator or 2. Upgrading to a boost controlled model will be available (requires tuning changes)
Next is the CHRA, which is custom cast around the stock turbo footprint and designed to accept our wheel designs, as well as updated internals with a more robust thrust bearing over the stock design. Following the factory, footprint allows all factory lines to be reused, with no need for additional lines or adapters. True plug, and play. These are Journal Bearing units.
Wheel sizes are as follows:

GC Rated at 600-650WHP (G30-770)
Turbine Wheel – Material Mar-M246
• Inducer 60mm
• Exducer 55mm
• 9-blade Garratt G-series profile Reverse Rotation Mar-M246
• 9mm Shaft diameter
Compressor wheel
• Inducer 58mm
• Exducer 76mm (81.24 Extended tips)
• 9-Blade Custom blade design reverse rotation

GC+ Rated at 850-900WHP (G35-1050)
Turbine wheel Material Mar-M246
• Inducer 68mm
• Exducer 62mm
• 9-Blade Garrett G-Series Profile Reverse Rotation Mar-M246
• 9mm shaft Diameter
Compressor wheel
• Inducer 66mm
• Exducer 84mm (90mm Extended tips)
• 10-Blade Custom profile design reverse rotation