Turbocharger, Intercooler, Diverter/Blow-Off Valve

Info

• "2.0T FSI - Which turbo is it?"[vwvortex]
  

• APR K04 kit [vwvortex]
  

• Large list of parts needed for a K04 conversion, with a large photo of all the parts, each part annotated with its part number (including S3 injectors). [vwvortex]

• Boost pressures of APR-chipped 2006 MkV GTI [vwvortex]: "...15-16 psi then holds steady at 14 and tapers down to 10 at redline

• AWE's boost gauge, in left side air vent[vwvortex]

• Splicing in AWE no-buzz fitting into AWE boost gauge's reference line to stop gauge from buzzing. [vwvortex]

• Why a boost gauge may show vacuum readings but not boost readings, and how to debug. [vwvortex] (Gauge in question is a New South Performance boost gauge.)

• Adjusting New South boost gauge to read zero when car is off [vwvortex]: adjust gauge using nut on back of gauge.

• A good explanation of "turbo surge":

  "Typically, surge occurs immediately after the throttle plate is closed while the turbocharger is spinning rapidly, such as between shifts or when decelerating. During surge, air pressure increases between [the compressor and throttle body], which reduces the air flow at the compressor. If the air flow falls below a certain point, the compressor wheel (the impeller) looses its "grip" on the air. Consequently, the air in the compressor stops being propelled forward by the impeller and is simply spinning around with the wheel, which is still being rotated by the exhaust gas passing through the turbine section. When this happens, the pressure build-up at the discharge opening forces air back through the impeller causing a reversal of air flow through the compressor."

• Another explanation of "surge":

  "Surge is the situation when the compressor "spits out" more air than the engine can swallow, which causes a backup of air at the intake and it actually creates reverse-flowing pressure waves that can be very damaging to the turbo."

• Diagnosing a bad diverter valve [vwvortex]: pic, location, symptoms (DTC codes etc.) and solution.

• Pic of a busted diverter valve from a 2006 MkV GTI:
  

• Part number for VW's revised "C" diverter valve [vwvortex]:  06F 145 710 C
• Part number for VW's revised "G" diverter valve:  06F 145 710 G

• A few accounts of aftermarket diverter valves that work well [vwvortex]

• Forge Motorsport Replacement Vacuum Operated Piston Diverter Valve for VAG 2.0 FSiT [vwvortex]: ECU controlled, etc.

• Forge spacer/vent valve (left) and adjustable vent valve (right) [vwvortex]:
  

• Intensive research of Forge spacer valve's effects on boost response and duration, surge potential, etc.

• "Blow off valve" causes incorrect air/fuel mixture [vwvortex]

• Stock (top) versus Neuspeed (bottom) turbocharger discharge pipe:
  
  Stock (top) versus Neuspeed (bottom) turbocharger discharge pipe's flange.
  

• Eurojet Racing's front-mounted intercooler on an Audi A3 2.0T FSI [vwvortex]:
  

• Intercooler misters:
  • "Who is going to be the first to get intercooler misters..." [vwvortex]
  • Tech article at audiworld.com on installing an intercooler mister on an Audi S4, plus before- and after- intake air temperatures.
  • Info on "Usually Sideways Rally Team (USRT)'s intercooler mister system

• Pics of Eurojet throttle body pipe [vwvortex]:
  
  Stock TB pipe & EA (Engine Amplification) pipe:
  

• "Noise maker" pipe in GTI (a.k.a. the "EA" pipe, "Engine Amplification") versus similar pipe in Jetta GLI and in Audi A3:
  • Pics:
    • Pipe from an Audi A3:
      
    • Pipe from a Jetta GLI:
      
    • Pipe from a GTI:
      
  • Info & pics on GTI pipe [vwvortex]: 54" of tubing at about 1" in diameter on the average!
    
  • Pointers on swapping out the GTI pipe out & Audi A3 pipe in
  • Impression

• Replacing "noise maker" pipe with pipe from Audi A3

How-Tos

• PDF document on installing a Forge spacer/vent/"blow-off valve (BOV)", from http://www.ecstuning.com/stage/edoc/Forge20TBOV.pdf

• How to install a Forge spacer/vent valve/"blow-off valve", step-by-step with lots of pics

• DIY step-by-step w/ pics of HKS SSQ BOV [vwvortex]

• How to remove the noise pipe [vwvortex] in a MkV GTI:
  • Remove the 5/16" bolt 5/16 hex bit) on top of the radiator cover]:
    
  • Remove the T27 Torx screw inside the engine bay below the washer fluid resevoir:
    
  • Loosen metal clamps: on top of the pipe by the firewall, and by the oil dipstick:
    
  • Remove noise pipe:
    

• Replacing the "noise pipe" with one from the Audi A3 [vwvortex]

• Removing the noise pipe and plugging the holes w/ rubber plugs] [vwvortex]
  Pics are also saved here.
  More info on removing the noise pipe and plugging the holes w/ rubber plugs] [vwvortex]

• Excellent instructions on AWE "air vent" gauge installation, with lots of pics and notes
  Pics are saved here.

• New South boost gauge
  New South 's PDF on installing the boost gauge
  (which is also saved here).