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DIY - STi 8 Intercooler onto MY00 Classic

< Scooby LPG Conversion | | Air Filter >


The following article describes how to retrofit a Newage STi 8 top mount intercooler into a Classic - that's the newer Phase 2 models (e.g. MY00). My would you want to do this? Well the STi intercooler is larger and thus has better cooling properties. This will help lower the temperature of incoming air and make running higher boost safer.

Note: This is not a five minute job, be prepared for some real DIY.

Parts List

  1. STi 7/8/9 Intercooler (Approx £250).
  2. Re-circ Dumpvalve for above, should hopefully come with No.1
  3. STi 7/8 Left Hand Bracket/Stay (£20)
  4. MY00 Samco Hoses, Turbo (Approx £60, but I expect you already have these)
  5. Samco Superflex 32mm hose (Approx £27, for 1m)
  6. Short piece of Aluminium Extrusion (Approx £4, B&Q)
  7. Small piece of Aluminium 5mm plate
  8. A few M8 Nuts & Washers

Total Cost : £301 (if you already have the MY00 Samco's)


  1. 12mm Socket
  2. 12mm Spanner
  3. 10mm Socket
  4. Large Flat Blade Screwdriver
  5. Hacksaw
  6. Coping Saw
  7. Electric Drill
  8. 3mm Drill bit (for pilot holes)
  9. 8mm Drill bit
  10. File or dremmel to tidy cut/drilled edges.


Clutch Fluid Reservoir Modification

  1. Remove Standard Intercooler, including all associated Hoses and brackets.
  2. Remove heat shield from Clutch Fluid Reservoir.
  3. Remove Yellow lid from clutch Fluid Reservoir and remove fluid from reservoir using a Syringe.
  4. Remove Jubilee clip from base of Clutch Fluid Reservoir
  5. Remove Plastic Reservoir, ready for modification.
  6. Modify/shorten clutch fluid Reservoir by cutting approx 20mm from base
  7. Refit Reservoir and Jubilee clip and re-fill with removed fluid.
  8. Refit Lid and heatshield

Shortened Clutch Fluid Reservoir

Coil Pack Height Modification

  1. Remove HT Leads from Coil Packs, taking note of order.
  2. Remove Coil Pack from inlet manifold by removing the 3-Off 10mm bolts.
  3. Using a Right-Angled coping saw cut approx 5mm from each of the 3 aluminium coil pack posts.
  4. Refit Coil Pack to shortened posts, Refit HT leads.

Coil Pack height reduced

Samco Inlet Modification

This allows the Intercooler to fit closer to the throttle body and hence provides better bulkhead clearance and allows the cooler to sit at a more standard height.

  1. Shorten the Intercooler to Throttle Body Samco by approx 5mm.

Samco Inlet Trim

Samco Y-Piece Vs STi

Originally the owner fitted a 90 degree elbow to the Sti Alloy Y-piece, as recommended by a lot of other people that have done this. However, this does not fit too well and causes the Samco to twist and kink slightly. The problem appeared to be that the MY00 Samco bends slightly upwards and sits closer to the Intercooler.

The owner thought about attacking the standard MY00 Samco in order to get a better fit. But.....when inspecting the 2 types of induction pipework he noticed that the size/spacing looked the same between the STi Alloy Y-Piece and Samco Y-Piece. In fact the Samco appeared less restrictive.

Hey presto a quick swap and the MY00 Samco and Alloy fitting are on the STi Cooler and looking like they will fit.

  1. Swap MY00 Samco Y-Piece onto STi Intercooler…..then place STi 8 Alloy Y-piece on Ebay
  2. Adjust Samco Y-piece slightly (see photo) to provide a better fit when attaching to Turbo. Although the Samco is not tight up against it’s preferred marking, there is plenty of material to byte on with the Jubilee clips.

Note : Image below shows MY00 Samco Y-Piece fitted to STi Intercooler. STi Alloy Y-Piece is on the floor

Samco Y-Piece Swap

Samco Y-Piece Adjustment

Samco Flexi Re-Circ DumpValve fitting

  1. Cut Length of 32mm Flexi Samco (Approx 450mm)
  2. Fit Flexi Samco to Dumpvalve ‘Hard’ return pipe.

Flexi Samco DumpValve (angle 1)

Flexi Samco DumpValve (angle 2)

Fit Intercooler and Hoses

  1. Fit STi8 Left Hand Bracket to gearbox.
  2. Fit Intercooler to Throttle Body Hose, with loose hose clips.
  3. Fit Intercooler into Intercooler to Throttle body hose (you won’t believe how much easier this is with the 5mm trimmed of the hose earlier)
  4. While doing the above, also guide the Turbo Outlet Samco onto the Turbo, again remembering to have the hose clip already fitted loosely.
  5. Once both throttle Body and Trubo hoses are on, pull the turbo hose on tight and secure hose clip.
  6. Check Throttle Body connection is still secure, then tighten hose clips.
  7. Loop the Samco Flexi from the DumpValve return hose, under the intercooler, to protrude in the vicinity of the Dump Valve.
  8. Secure DumpValve to Samco Flexi, then Secure Dumpvalve to Intercooler.

Intercooler Hoses Fitted

Left hand bracket/Support

  1. Cut Length of Aluminium Extrusion, trim and Drill 2-Off 8mm holes. For this it is best to make your own measurements as each application may differ slightly.
  2. Secure Aluminium Extrusion Bracket to STi 8 Bracket and Intercooler. I fitted this to the underside in order to allow the Intercooler to sit lower.

Aluminium Extrusion

Left Hand Bracket

Right hand Bracket/Support

There are two options for tackling the right-hand bracket, see below:

Option 1 - Bend the bracket and fabricate a spacer:

  1. Place Bracket on floor and hit with hammer (see picture). This should bend the centre of the bracket slightly in order to clear the edge of the intercooler.
  2. The bracket can be bent in 2 directions in order to get it to line up with the existing holes. However, the owner didn’t want to bend it too much so made a spacer as shown below:

Bending Bracket


Right Hand Bracket Fitted

Option 2 - Use part of the old and newage bracket:

This option was preferred by 'WRX Ben' from the SIDC. The only difference is for the right hand bracket where he used part of the original and part of the newage bracket. Bolted them together and job done. He found this much easier than trying to bend the original bracket to fit.

Finished Article, with Strut Brace

  1. It may be required to pack between the Left/Right Brackets and Intercooler with Spacers/Washers in order to ensure the underside of the intercooler does not bang on the Bulkead/Gearbox bracket. The owner used 2-3 washers.


Running Report.....

After a bit of settling time the cooler was fouling slightly on the bulkhead when starting/stopping the engine, this was being caused by the Flat Four side to side movement.

Investigation found 2 problems :

Problem 1: One of the hose clip screws on the turbo To Intercooler Samco was fouling on the 'Right Hand Side' of bulkhead webbing surrounding the gearbox support, under the intercooler SOLUTION : Turn Hose Clip round i.e make sure both hose clips have their adjustment screws on the outside edges.

Don't fit Hose Clips this way, but rotate 180 Deg

Problem 2: The Left hand Intercooler Aluminium connection i.e where the Samco connects to the Intercooler (see above image), was also fouling the bulkhead webbing surrounding the gearbox support. this time on the 'Left Hand Side'. SOLUTION : place length of wood against webbing, and hit it with a hammer to bend it back a few millimetres.

You can now flex the intercooler left/right/up and down without securing the brackets and is does not foul anything. Once the brackets are fitted it won't move as much, so problem solved.

Information source - ScoobyNet forum thread DIY - STi 8 Intercooler onto MY00 Classic

Page last modified on August 20, 2009, at 09:13 PM
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