Forced Induction

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Oil Supply Line

  • 1x -6AN Male to 16mm x 1.5 Metric Male Adapter
  • 1x -6AN Female to -4 AN Male Reducer
  • 1x -4AN Stainless Steel Braided Hose (48")
  • 2x -4AN Straight Hose End

I have also found a site that sells the complete hose minus the adaptor needed to connect it to our block. The only thing is I haven't tried them yet so I can't say how well there lines are. The lenght will vary with your setup due to the mounting location of your turbo so you will want to measure after you figure out where the turbo will be mounted. Hose

You want -04 Straight to Straight Hose Assembly

Oil Return Line

  • 1x -10AN Stainless Steel Braided Hose (24")
  • 1x -10AN Straight Hose End
  • 1x -10AN 90 Degree Hose End

Fuel System

Fuel Pump

If your looking to make over 300 HP then you will need to upgrade the stock fuel pump to a walbro. If you need a pump for the 91-96 Saturn you will need to contact the company and tell them the year you need it for. Auto Performance

  • 97+ Saturn
  • FPG006 - high pressure kit


Our fuel rails can fit many different injectors. Any BOSCH/GM/Ford injector will be a plug-n-play, and many others will work. GM/BOSCH are very abundant and are rated at the proper fuel pressure for our cars (43.5 psi). The Ford injectors are rated at a lower operating pressure (39 psi), so when you see a Ford injector that is supposed to flow 32#, it actually flows 28.7#.

You probably want injectors that flow close to ~100# if you're shooting for BIG horsepower, if your goal is around 300 whp then go for ~75# injectors. Mid 250 whp go for ~50# injectors. Never base injector size off the boost pressure you are running, always base it off your horsepower goal.

The injectors are divided into two types. High impedance (~12-14 ohm) and low impedance (~2-4 ohm). If you want use your stock PCM to control the larger injectors:

- OBDI can use both types. High impedance injectors will flow a bit less, but only a tiny bit.
- OBDII can use only high impedance injectors. Running low-impedance might damage the PCM.

With a standalone, such as MegaSquirt, you can usually run either type of injector.


One of the most inexspensive standalones is the MS2 which is starting to become more rounded then the more expensive standalones. Once the GIOP board is done we will be able to drive all of our gauges and toss the stock pcm into garbage. Here is the link to the mega squirt manual. MegaSquirt

With MegaSquirt you can either run fuel-only, or you can also control spark. For fuel only, the most basic MS will suffice (MS1, pcb v2.2) you will not throw any SES lights if you control fuel only and use separate sensors. For fuel and spark, I recommend MS1 pcb v3.0, however you can get away with using pcb v2.2. You WILL throw a SES light trying to control spark. The reason you want to run pcb v3.0 is because of built-in noise reduction and ability to run either type of injectors out of the box. It is EXTREMELY easy to mod your MegaSquirt to control OBDI ignition on a Saturn. A bit more work is needed to convert an OBDII system to OBDI to work with MS.

MegaSquirt is extremely versatile and allows these features on our cars:

- Full fuel and spark control
- Launch control
- Flatshift *
- Traction control*
- Soft rev limiter*
- Nitrous control
- Water injection control
- Boost control
- Knock sensing
- AUX outputs to control shift lights, cooling fans, solenoids, relays, etc
- Many other features I can't currently remember

(*requires spark control)


Cool Radiators makes an all-metal radiator and it is thicker then the stock one. They are 2 Row Full Race Radiators. The core is 2 1/16 inch thick and they cost around $250 plus shipping but are only for cars with manual trannys. I was told that they made 55 of these radiators last year 2005 and just sold the last one to me on 08/10/06 but will be making more in October of this year and to check back on there site since they will list them again once they become available for sale.Cool Radiator

A Civic aluminum half-radiator is another good (and cheap!) alternative, especially with turbo setups that require more space. The Civic radiator is half the size, but holds the same amount of coolant, making it an excellent choice. Mounting brackets will need to be fabricated and lower coolant hose routing are the only two issues that might come up.


Alright, you want to base your turbo choice on the desired power level. Do you want your car to be quick in city traffic? Do you want it to have good mid-range but a bit of lag from the start? Or do you want it to be a dyno queen putting down over 400 whp, but not making boost until really high in the rev range?

Once you decide your desired power goal, let's discuss how to pick a proper turbo. This requires learning how to read a compressor flow map. You will need to understand what this map means, and you will need to review many of them when picking the perfect turbo. I will skip the discussion about flow, pressure ratios and efficiency and go straight to the meat to keep this short.

A 1.9L DOHC LLO Saturn engine flows around 170 cfm @ 5500 RPM @ 100 kPa. This is a very rough figure, and yours will depend on your breathing mods (head work). The better you can make your engine flow, the more POWER you will put out at the SAME boost level. So, in this scenario proper breathing mods become very important!

Ok, now let's decide on the power level. Stock engines typically can handle 220 whp without too much trouble. That's roughly 250 bhp (crank horsepower). Let's see here, if your engine flows 170 cfm and makes 124 bhp, then to make 250 bhp you will need to flow:

(250 bhp / 124 bhp) * 170 cfm = ~340 cfm

I want my cars to have nice mid-range, I can handle a bit of lag but not too much. So we need to find a turbo that can flow 340 cfm and is efficient in the mid-range.

Let us consider a TD06H-20G turbo: [1](click for flow chart)

This is not a bad turbo if you plan on running 10 psi and have good spool-up. 300-350 cfm @ 10-12 psi is right there in the good efficiency range. There you have it, there really isn't much else to your turbo selection. Someone shooting for lower spool times might opt for a smaller turbo that has a lower boost threshold, but remember you will be sacrificing top-end to get that low-end torque. A GOOD turbo for an average saturn looking to make 250-350 bhp is a good old "Super 60" that puts the powerband in the mid-high RPM range and will not create strong boost at cruising conditions.

Turbo manifolds

Along with the fuel system you will want to decide how much power you want to make before picking your turbo manifold. If your looking to make under 300 HP a log manifold is better for you which will be cheaper and last longer then a equal length manifold. The equal length manifold will flow more air allowing you to get more out and bring more in thus increasing the efficiency of your turbo and making more HP.

A good alternative to making your own manifold or buying one that is made specifically for a saturn is to modify a DSM manifold to work on your S-Series. Here is an article on how to do that: DSM Manifold on a Saturn

Wideband O2 Sensors

There are many WB02 sensor that you can use to monitor your Air Fuel Ratio while running boost. I have some listed below that work very well.

  •'s JAW Assembled or as a kit (JAW Assembly)
  • Innovate Motorsports LC-1 without the gauge it goes for $199
  • AEM UEGO is a popular choice that comes with a gauge, has outputs to standalone systems (like MS) and costs around $250
  • The PLX M-300 around $300
  • Zeitronix ZT-2 It costs more money then most but has a lot more features. Around $400
  • Tech Edge Australia based manufacturer of various WBO2 controllers and gauges. Completes systems start at ~US$450. Just the controller without sensor or display starts at ~US$220.