450cc DSM Fuel Injectors



I had 2 sets of used 1st generation DSM 450 cc fuel injectors to replace my stock 360cc fuel injectors. The injectors were sent to Cruizin Performance to be cleaned and flow tested. This was done for only $10 per injector, which was quite a bargain compared to the few other available options. The main source for reference was Stealth 316 - Changing Fuel Injectors. The preliminary steps are identical to spark plug replacement. However, I opted to use a different procedure for the injector removal. I chose to skip steps 1-6 of the "Removal" section, and instead I unbolted the bolts on the ends of the fuel rails on the passenger side. (There are 2 bolts per fuel rail) The ends were then carefully slid away from the fuel rails, taking care to not damage the o-rings. Then both fuel rails were removed, while still attached to each other, on the end toward the driver side of the car.

I would recommend that you install new fuel injector o-rings. They can be obtained from Mitsubishi, or you can buy universal ones at an auto parts store, or a hardware store. The correct size is 12mm OD x 8mm ID x 2mm thickness.

Once everything was installed, I changed my S-AFC settings to -15% across the board. The car ran VERY poorly, and I searched for quite some time to find the source of the problem. I attempted to vary the S-AFC settings, but it did not fix the problem. At -15%, the car would not idle and stay running for any length of time. When it would momentarily run, the idle was very rough. By turning the S-AFC settings to very high positive values, the car would idle, but not well. Eventually, I searched the engine enough times, and discovered that the clamps for the intake hose after the MAS were loose. (I have NO idea why/how this happened, because I had not disconnected them during the fuel injector installation.) After tightening these clamps, and changing the settings back to -15%, the car ran, and idled relatively well.

I used my Pocketlogger to record a few runs with the new injectors and these settings. Due to road conditions, I was only able to perform a pull in 2nd gear. The pocketlogger showed virtually no knock, and the o2 readings were rich (WOT values maxed near .94 to 1.00 V)

DSM (450 cc/min) Injectors








Installation Pictures














Stock (360cc/min) Injectors






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