APS Turbo Inlet Pipe Installation Guide


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Components - Release 1.0
Model No.: APSWRX-CID/01
Application: WRX/STI 01 ONWARDS

The above diagram shows APS components in the approximate location and orientation when installed.

Item No. Part No. Description Qty.
1 995-222-000 DUCT - SILICON - AIR INTAKE 1
2 995-022-500 DUCT - S/S - AIR INTAKE 1
3 995-222-800 HOSE - SILICON - COMP INLET - 55/60mm 1
4 995-222-900 HOSE - SILICON - COMP INLET - 3.0" 1
5 000-928 CLAMP - HOSE - 70/90 3
6 000-907 CLAMP - HOSE - 60/80 (9mm wide) 1
7 000-908 CLAMP - HOSE - 70/90 (9mm wide) 1
8 995-994-100 HOSE - BREATHER - 3/4"/0.5" 1
9 995-994-200 HOSE - BREATHER - 3/4" - STI 1
10 000-947-200 TEE PIECE - 3/4" BARB - STI 1
11 995-102-200 ADAPTOR - SENSOR VENT 1
12 995-994-300 HOSE - BREATHER - 5/8" - STI - LHS 1
13 995-994-400 HOSE - BREATHER - 5/8" - STI - RHS 1
14 000-947 TEE PIECE - 5/8" BARB - STI 1
15 995-994-500 JOINER - ST. - 5/8" - STI 2
16 995-073-850 BRACKET - REGULATOR MTG 1
17 000-011-100 BOLT - HEX - 8mm x 1.25 x 16mm (SEMS) 1
18 000-853-062 HOSE - PUSHLOC - 5 x 620mm 1
19 000-853-113 HOSE - PUSHLOC - 5 x 1130mm 1
20 000-827-045 HOSE - RUBBER -VACUUM 3.00mm x 450mm 1
21 000-916 CLAMP - HOSE - FUEL INJECTION (14) 4
22 000-911-023 CLAMP - HOSE - SPRING, 5/8" HOSE 7
23 000-911-027 CLAMP - HOSE - SPRING, 3/4" HOSE 5
24 000-992-150 SPACER - 18mm O.D. x 8.5mm I.D. x 7mm 1
25 000-987-178 TIE STRAP-NYLON 4.8mm x 178mm 4
26 000-931 CLAMP - HOSE SUPPORT 15/20mm 1
27 000-939-822 CAP - BLANKING 8mm I.D. x 22mm 2

Installation Guide - Release 1.0
The installation of the APS Compressor Inlet Duct requires the removal of the intake manifold assembly (including the TGV assemblies). This is not a difficult operation when performed in accordance with the Factory Service Manual instructions relevant to your Subaru WRX or STI model.

APS strongly recommends that you follow the Factory Service Manual.

The following images and written guide are based around the 04/05 U.S. specification STI. The APS Compressor Inlet Duct can be installed on 01 onwards WRX or STI, U.S. or International specification, however detail variations in the crankcase breather line configuration and modifications will be required. Some of these are referenced however in all cases, they are very simple and straightforward when the stock configuration is used as a guide.

1. Remove the stock intake manifold assembly (includes the TGV units and stock compressor inlet duct) in accordance with the Factory Service Manual.

Remove the stock fuel line retaining bolts. Remove the stock fuel rail retaining bolts and rotate the fuel line as shown above.


Remove and discard the stock rubber fuel lines connected to the stock fuel pressure regulator. Remove the stock fuel pressure regulator from its stock mounting bracket.

Cut the stock fuel pressure regulator mounting bracket as shown and discard the cut piece.

Whilst lifting the fuel line shown above for clearance, remove the stock plastic compressor inlet.


Install the new APS Compressor Inlet Duct as shown but DO NOT tighten the attaching bolt at the front of the stock inlet manifold.


Reinstall the modified stock fuel line assembly ensuring that the spacer (Item 24) is installed between the modified fuel line bracket and intake manifold as detailed above.

Install new fuel line (Item 18) and blank off cap (Item 27) as shown.


Re-Install the stock compressor by-pass (B.O.V.) hose and the stock small vacuum hose at the front of the intake manifold.


Install the silicon compressor inlet hose (Item 3 or Item 4 depending upon your turbocharger inlet size) - Item 4 shown.

Note orientation of silicon hose relative to stock breather tube
Note hose clamp position to facilitate clamp adjustment after completion of installation.

  • Item 3 - for stock or near stock compressor inlet connections
  • Item 4 - for 3" High Flow compressor inlet connections

Position second hose clamp loosely over the silicon compressor inlet hose orientated as shown above.

Remove the stock breather line and cut the mounting brackets as indicated above. Discard the breather line. Note this is an STI only component and therefore not relevant if installing on a WRX model.

Reinstall bolt that was used to support the stock breather tube (that has now been discarded).


The previously removed stock STI breather line is replaced by a combination of stock and new moulded hoses.

Install tee piece (Item 14) in the stock rubber elbow as shown. Install moulded hoses (Item 12) on LHS of tee piece (Item 14) and moulded hose (Item 13) on RHS of tee as shown.

Install joiners (Item 15) between these hoses and stock breather hoses at either outboard end.

Retain all hoses using hose clamps (Item 22).


The entire stock intake manifold assembly with new APS compressor inlet duct can be re-installed in accordance with the Factory Service Manual instructions - whilst paying particular attention to the fuel return hose (Item 18) previously installed. This fuel return hose must be routed as shown above.


Tighten hose clamp (Item 5) previously loosely positioned over the silicon compressor inlet hose as shown.


For WRX, install 3/4" - 1/2" breather hose (Item 8) between the large 3/4" barb on the front of the compressor inlet duct (Item 2) and the breather tube connected across the front of the top mount intercooler.

For STI, the breather hose (Item 8) must be cut as shown above. The tee piece (Item 10) is then installed as shown. This delivers provision for STI only breather hose (Item 8) to be installed as shown.

Retain all hoses with clamps (Item 23).


STI only breather hose (Item 9) is connected to the stock sensor vent immediately in front of the turbocharger compressor housing using adaptor (Item 11) as shown.


Relocate the stock engine earth lead as shown in the following detail. Install new fuel pressure regulator mounting bracket (Item 16) as shown.

Install the stock fuel pressure regulator to the new bracket using 8mm hex bolt (Item 17).

Connect fuel return hose (Item 18) previously installed to the stock fuel pressure regulator as shown. Retain with hose clamp (Item 21)

Install fuel return hose (Item 19) from the stock regulator to the stock metal line returning to the fuel tank, at a point immediately adjacent to the front left shock tower. Retain with hose clamp (Item 21) and support with hose support clamp (Item 26) to the brake master cylinder as shown.

Install new vacuum sensing hose (Item 20) between the relocated stock fuel pressure regulator and the stock sensor port barb in the stock intake manifold.


Detail of fuel hose connections including blank-off cap (Item 27) installation onto stock fuel return line.


Tighten bolt mounting compressor inlet duct (Item 2) to the stock intake manifold.

Install new silicon air intake hose (Item 1) between the air cleaner (or cold air intake) and compressor inlet duct (Item 2). Retain silicon hose with hose clamps (Item 5) as shown.

17. Check back over all connections and hose routing to ensure that all components are secure. Check any other accessories that may have been disturbed during this installation.
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