I thought I would share how to install the RaceChip Ultimate on the F15 N55 engine since the instructions included are severely lacking.
I'm going to consolidate some pics from other posters as it's similar to other piggy back installs.
In the box you will get the RaceChip module and 2 wiring Harnesses:
The reason for 2 harnesses is because there are 2 types of connectors used in F15 vehicles, depending on when yours was manufactured. The weird thing is the ones that don't fit actually have the same grooves as the OE plugs, so don't rely on that as an indication of which harness to use. The correct harness will "click" in. On my 2015 the Purple harness was the correct one.
*NOTE: They come shipped with the Dummy plugs connected to the harness (they are wrapped in heat shrink. Take these off before attempting to plug into the RaceChip module).
The Harness has 2 "Y" connectors (4 connections total). One for the MAP Sensor pictured here:
This requires you to remove the air filter box using a flat screwdriver to loosen up the hose clamp and Torx T25 for the 6 screws on the airbox. It will look like this:
Close up of the MAP sensor behind air box:
and the other for the TMAP sensor pictured here:
Here are both plugs in relation to the engine bay:
At each location you simply plug the appropriate "Y" plug into the engine connector and the other intercepts the factory plug. Now you simply plug the harness into the RaceChip module and zip tie everything securely.
At this point you should start the car and drive it around. If everything seems OK and no engine light comes on now you can move on the increasing the power.
This is where the manual make a little more sense. However, being that the manual talks in generic terms it will mention that on the S2 dial "0" is factory and turning it to "1" is a 22.5% (or so) increase in power. That's fine if yours is shipped with an initial setting of "0", but mine was shipped on an initial setting of "B". Bottom line is when increasing your tune, it is recommended to turn one click on the dial from your factory setting and then drive the car to allow it to adapt.
opasha posted this procedure which I would recommend to obtain the best setting for your individual vehicle:
(1) open up the box using a T10 torx screw driver.
(2) look for the dial marked "S2". The dial will have alphabetical and numerical markings. The most important thing to remember is that position "8" is the minimum power/torque setting and position "7" the maximum. Each notch clockwise, according to RaceChip, adds another 1.5% of power/torque.
(3) leave dial "S1" alone i.e. don't make any adjustment to it.
(4) look at dial "S2" and see what the default factory setting is.
(5) to tune the box for increases in power/torque, turn the dial "S2" clockwise one notch at a time.
(6) after each step increase, start and drive the car a bit to check if there are issues or not.
(7) if step (6) was ok, drive normally for sufficient kilometers (say 50 ~ 100) to let the ECU adapt.
(8) if there were no issues after covering sufficient kilometers, take the car for a stress drive before increasing another notch in dial "S2". By stress drive, I mean the engine should reach 6000 rpm. What I did was to switch to manual and ran in 4th gear.
(9) if step (8) was ok, repeat from step (5).
(10) eventually, you will reach a setting in dial "S2" when the drive becomes less smooth and or according to RaceChip, the CEL may pop up. When this happens, turn the dial two notches anti-clockwise and that will be the position for best power/torque for your car."
That's it. If you have any questions just reply or shoot me a PM.
I would also like to thank
opasha and
r33 for their pics and posted information used in this post.
