2013 Subaru Impreza WRX STI - Project Log

[Jasen]

pg,

maybe a few louvers/slot's in the front belly pan to help it breath a bit.

[jedi_sol]

This version works by cutting the signal from the Crankshaft position sensor. The engine will shut off cleanly and instantly and will not throw any Check Engine Light Codes.

Materials used:
1) 1 smallest precision flat head screwdriver (or anything really pointy and small)
2) 1 needle nose pliers
3) 2 quick splices
5) 2 female spade connectors
6) 1 switch

Locate the engine harness on the upper left side of the engine bay



On the ENGINE side of the harness, press down the black release tab, The Grey bracket should pop up


Push the grey bracket 90* backwards towards the firewall to release the engine harness


Use needlenose pliers and pull out the white locking thing (it pulls out easily) to expose the small male connectors



CAREFULLY pry out the grey wire holders from the ENGINE SIDE of the harness about halfway…be careful not to break the side locking tabs


Now you should be able to release the male pin connector. Firstly, The Crankshaft position sensor is pin #3 of the FIREWALL SIDE of the harness (female connectors)…




Therefore, find the corresponding MALE pin connector on the ENGINE side of the harness… it’s the BLUE WIRE, top row, 3rd from the LEFT if you’re looking at the wire harness from the backside where all of the wires are coming out


There is a small locking tab on the TOP of the spade connector. Insert the small precision flathead (or something flat and pointy) to release the tab…then you should be able to pull out the male spade connector from the back.



Now, grab your two wires and 2 quick splices. Splice one wire onto the BLUE wire (ENGINE SIDE) male pin side. Splice another wire onto the White wire (FIREWALL SIDE) on the female side.


FEMALE SIDE...top row, WHITE WIRE, 3rd from the RIGHT


Thread the wires through the fender,

…through the door jamb…


….Into the passenger compartment of the car.


Tuck the wires up behind the glove box and behind the center consol


Now with the two wires…splice in some female spade connectors into your switch.



You should end up with something like this…

Finally, plug in the ENGINE HARNESS, tape up the exposed male pin connector to protect from shorting out and enjoy your new kill switch!

[jedi_sol]

I finished mounting the side skirts


ABA Testing
2 mile stretch of freeway
got up to speed at 60mph...set cruise control...reset the trip meters on my torque app at pre determined start and end points
68*F outside temp
1:00am at night (so the freeway is clear of traffic)

SKIRT ON - total average: 26.65mpg
Direction 1:
27.6
28.8
28.3

Direction 2:
24.9
25.3
25.1


SKIRT OFF - total average 26.79 mpg
Direction 1:
28.6
29.4
29.1

Direction 2 :
24.2
24.7
24.6
24.7

Skirt ON - Total average 26.5 mpg
Direction 1:
29.7
28.2
28.7

Direction 2:
24.1
24.1
24.8

Skirt ON: 26.575 mpg
Skirt OFF: 26.79 mpg

That's only a 0.215 mpg difference between skirt off vs skirt on. So it appears inconclusive as to the effectivness of the side skirts.

Some observations:
as the night wore on, i noticed at the air was getting more foggy...thus increased moisture in the air causing more air drag at the end of the testing vs at the beginning of testing.

My first "skirt on" run..i didnt use my torque app's gps to record the speed when setting the cruise control...i just "eyeballed" the analog speedometer when setting the cruise control. Therefore, the cruise control might have been fluctuating between 59mph to 61 mph...thus scewing the results.

Final Thoughts:
1) the skirts by themselves may not help improve mpg, rather, i would need to add a front, middle, and rear underbelly tray to really take advantage of the side skirts

2) even if i do experience a 0.2mpg hit...i'll keep them on because they look really cool!

[jedi_sol]

Finished the upper grill block
Applied velcro


I want the grill block to tuck underneath the hood to create a smooth transition, however, the grill block i made was too short so i cut off the top and tucked into the hood..however, there is now a gap.


I "filled" the gap with tape (replaced with Gorilla Tape). I used tape because i wanted to keep the top "flap" flexible so i can easily remove the grill block when needed



Paint!



ABA TESTING to follow....

[Awd180]

How much did you decrease the distance from ground on the side skirts, it looks like an inch maybe 2. To see something noticible mpg wise try more than 2" decrease. You might see more from lowering springs but it takes a lot more labor and money.

Also, if you hadn't done so yet, remove the splitter in the scoop and replace with a mesh screen. I foil taped the screen to the ic, allowing more air to flow over the hot side, also foiled the sides of the ic and added spacers to increase the pitch on the ic.

[UltArc]

Looking good! The velcro idea seems like a better setup than zip ties (what I use).

[jedi_sol]

Originally Posted by Awd180

How much did you decrease the distance from ground on the side skirts, it looks like an inch maybe 2. To see something noticible mpg wise try more than 2" decrease. You might see more from lowering springs but it takes a lot more labor and money.

Also, if you hadn't done so yet, remove the splitter in the scoop and replace with a mesh screen. I foil taped the screen to the ic, allowing more air to flow over the hot side, also foiled the sides of the ic and added spacers to increase the pitch on the ic.

the rain gutter drip is 3" tall...so that's a 3" decrease in distance from the bottom of the car to the ground...so perhaps some other factor is at play to explain why the ground skirts are not showing an mpg increase.

Can you take a picture of your Intercooler setup with the mesh screen? im a visual kind of guy so i want to make sure me and you are on the same page.

[Awd180]

As you can see not much has changed in 10 years, beyond 2.0L -> 2.5L of course there are some differences with the sti and wrx (bigger turbo, injectors, and some others). As you can see I had some battery issues recently, turned out the connector next to the red boot on the alternator had some rust on the center terminal. I fixed the old 90amp, but found a 110amp newer alternator for cheap. In my search I've seen some even bigger alternators but they cost a lot more.

[jedi_sol]

Originally Posted by Awd180

As you can see not much has changed in 10 years, beyond 2.0L -> 2.5L of course there are some differences with the sti and wrx (bigger turbo, injectors, and some others). As you can see I had some battery issues recently, turned out the connector next to the red boot on the alternator had some rust on the center terminal. I fixed the old 90amp, but found a 110amp newer alternator for cheap. In my search I've seen some even bigger alternators but they cost a lot more.

Neat mod! I guess this is to increase air flow, yet at the same time protect the Intercooler from bugs/rocks etc?

[Daox]

That is the same way I made the kill switch in my 97 Paseo. It works great, but it gave a check engine light... I find it odd that yours doesn't