NG 900/9-3 Viggen Intercooler

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This upgrade applies to the NG 900 and 1999 base 9-3. All 2000 and later 9-3s and the 1999 SE (HOT) and Viggen come with the Viggen Intercooler.

This upgrade is highly recommended, it is well worth the effort and cost. There is a noticeable increase in power and spool-up is quicker. On Maptun's website they indicate that there is a 10 HP increase. I have also seen verification of this on Saab Net where someone posted a before and after dyno. There was an increase of 11 horsepower 12 nm of torque.

Using some string I measured the distance from the turbo exit to the throttle body transition casting, the total length was 10'9" with stock setup. With the Viggen Intercooler the length was reduced by 25% to 8'2", plus a reduction of approximately 260 degrees of bends.

Viggen Intercooler Dimensions: Core: 167.5mm high Core: 555mm length exposed to air flow Core: 56.5mm deep.

Cost and Difficulty

  • Cost: $175 Intercooler, $100 Each Side Hose, $11 Radiator Hose
  • Time: 4 hr
  • Difficulty: Moderate

Part Numbers

  • Viggen Intercooler: 4729521
  • Passenger's Side Hose: 4729950
  • Driver's Side Hose: 4729968 (Not Required - See Bottom)
  • Lower Radiator Hose: 4963872



Radiator coolant must be drained to install new lower radiator hose. A new passenger side hose is required but it is possible to use the existing drivers side hose by removing the clamp that holds it to the engine block and sliding the hose down and retightening. The old intercooler is removed and the Viggen Intercooler is installed in the same location with the same bolts. The installations of the Viggen Intercooler does not require the moving or relocation of any other parts or pipes other then the ones mentioned.

Full Installation Instructions

  1. This installation is for installing the Viggen intercooler with the new passenger side hose and reusing the driver's side hose (Number 6 pictured to the right). Begin by jacking up the front and removing the bumper (Bumper instructions written under Tips). The next step is to remove the stock intercooler, start by first removing the pipes from the turbo to intercooler (2,3,4) and then take the intercooler to throttle body pipes (5,6,7) off by remove the clamps (11) that secure them to the throttle body transition casting. There is also a metal clamp on part (6) which secures it to the engine block (not pictured). This clamp needs to be removed from the engine block and the hose because it will not be reused for the reinstallation.
  2. The stock intercooler is held in place by only two bolts on either side. All pipes are held in place by circular pipe clamps (11,12) that can be loosened with a flat head screwdriver or a hex socket.
  3. Two pipe clamps (11) need to be saved from this removal to be reused on the new passenger side pipe unless new clamps were purchased. All parts of the driver's side hose with be reinstalled in the same layout as pictured here (5,6,7).
  4. With the stock intercooler removed the next step is to drain the radiator fluid. The drain is located on the driver's side at the bottom of the radiator. There is a hex wrench screw that must be loosened to allow the fluid to pore out. First remove the cap to the radiator fluid chamber to equalize the pressure during the drain. As soon as the screw is loosened radiator fluid will pore out of the hex hole in the screw. I used a plastic trash bag to catch the fluid because it is not possible to position a bucked directly under the spout. A small hose might work well but there is not much room to maneuver beneath the spout. The trash bag worked rather well without much spilling
  5. Once the radiator fluid has drained remove the lower radiator hose on the passenger side and install the new one. I suggest using new pipe clamps because they will be easier to tighten in the confined space. Don't refill the radiator fluid yet, it is easier to install the turbo exit pipe when the radiator hose is empty.
  6. The installation of the Viggen intercooler is next. Reattach the bolts on either side of the Viggen intercooler.
  7. The exit for the Viggen Intercooler is about 4" lower than stock. This requires an extension to be made so that the hoses will fit together correctly. All parts are leftover when the stock intercooler is removed: Two ring clamps, 4" of aluminum pipe, and the cut off straight section of a rubber elbow.