Turbo Kit for Audi A4 A4 Avant 1.8T 20V (1997-2004) 1.8L

Complete intercooled T3/T4 turbo package for the 1997–2004 Audi A4 and A4 Avant with the 1.8L 20-valve turbo four (1.8T). It's built around a 321 stainless tubular T3 manifold and a hybrid T3/T4 turbo, with a 35mm external wastegate, front-mount intercooler, boost controller, blow-off valve, turbo timer, catch can and fuel-system parts in one box. A/C and power steering stay in place, and it works with manual or automatic transmissions. Expect roughly 100 hp over stock at a conservative 8 psi with a proper tune. The 485+ hp figure is the hardware's ceiling at 25+ psi with a built engine, fueling and supporting mods, not a dyno result for a stock car.

Why this kit

• TIG-welded 321 stainless tubular manifold with large primaries and a thick T3 flange that carries the turbo's weight
• T3/T4 hybrid turbo with a .57 trim compressor and .50 / .63 A/R housings
• 35mm external wastegate plus an adjustable boost controller
• Includes the extras most kits leave out: adjustable fuel pressure regulator with gauge, billet fuel filter, catch can, slim fan and electronic turbo timer

Package Includes

• (1) T3/T4 hybrid turbocharger, oil fitting gaskets and mounting studs
• (1) Stainless tubular turbo manifold, T3 flange, polished, with gaskets and hardware
• (1) Front-mount aluminum intercooler, 2.5" inlet / outlet, under 2% pressure drop
• (1) Aluminum intercooler piping kit: (2) 2.5" straight pipes, (2) 90°, (2) 60°, (2) 45° bends, (2) 2.5" 90° silicone couplers, (6) 2.5" straight silicone couplers, (16) stainless worm-gear clamps
• (1) 35mm external wastegate, 2-bolt flange, gaskets and flanges
• (1) Adjustable boost controller
• (1) Blow-off valve with install kit
• (1) Electronic turbo timer with LED display and wiring
• (1) Adjustable fuel pressure regulator with gauge
• (1) Billet aluminum high-flow fuel filter, -6AN fittings
• (1) Oil catch can with install kit
• (1) Slim reversible cooling fan
• (1) Coolant sensor bung adapter, 38mm
• Oil feed and return lines, vacuum line, gaskets and hardware

Turbocharger Specs

• Type: T3/T4 hybrid, wet-float bearings, balanced
• Compressor: .57 trim wheel, .50 A/R housing, 3" inlet, 2" outlet
• Turbine: .63 A/R housing, T3 inlet flange
• Oil inlet: 1/8" NPT

Exact Fitment — Audi

• 1997–2004 Audi A4 1.8T (B5 and B6), sedan and Avant, FWD or quattro
• Longitudinal 1.8T 20V engines, e.g. AEB, ATW, AWM, AMB
• Not for A4 2.8L / 3.0L / 3.2L V6, 2.0T (2005.5+), 2.0L naturally aspirated or TDI engines
• Not for the transverse A3 or TT: those use a different engine-bay layout
• The intercooler piping is universal and is routed to suit the longitudinal A4 bay, so expect custom fitting

Not Included

• Chassis-specific downpipe and exhaust beyond the turbo
• Larger injectors, fuel pump and ECU tune (required)
• Boost gauge, wideband and air filter

Installation Notes

• Professional installation strongly recommended. Expect cutting and fitting of the universal piping and fabrication of the downpipe
• Replaces the stock K03/K04 turbo, manifold and side-mount intercooler. Check bumper clearance for the front-mount
• Prime the turbo with oil before first start and check for leaks at feed and return
• Keep boost low until fuel and tune are upgraded