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jedi_sol 08-07-2013 09:46 PM

2013 Subaru Impreza WRX STI - Project Log
Hi everybody,
Finally saved enough to buy my dream car, a Subaru WRX Sti. I couldn't last a month before getting the ecomodding bug.

Since the car is brand spaking new, i am mostly sticking to simple aero mods that will not permanently alter the look of the car (gonna hold off on rear wheel skirts or kaamback's for now).

current mods:
1) side mirrors folded in
2) Torque App to track mpg's
3) 90% lower grille block
4) Fog light covers
5) tires at 42 psi (max sidewall 51psi)
6) upper grill block

Future mods:
2) under belly tray (the nice thing about getting a sports car is that the bottom is already very flat from the factory).
3) rear underbelly tray

Current mods in the works:
1) side skirts

Side Mirrors Folded in: Version 1.0:

Used a simple bubble mirror with an aluminum bar, double sided tape.

The mirror was too heavy and the heat casued the double stick tape to loose its stickiness, the mirror kept falling off.

Version 2.0: i used a different style blind spot mirror, double sided tape attached the mirror itself. This gives me a better view of my blindspot since the mirror is on the outside now

Torque App:
used my old HTC android phone with a windshield suction mount. The app is great, however, the mpg's max out at 255mpg when coasting, therefore, the total average mpg's are slightly at best you'll get an accurate ballpark figure.

It turns out the old rule of thumb of "80% load to accelerate" may not be the best for this car because in 6th gear at 80% load puts me in which the mpgs drop to 5mpg.

Building the lower grill block:
Since it's a turbo car, i know engine temps will be very important to keep an eye on, therefore, i recycled my old grill block from my del sol and cut the block into sections so i can attach/remove sections if temps start to creep up. I also left about a 1 inch clearance on the bottom of the grill block to still allow air to flow in if im stuck in traffic.

The nice thing about the STI bumper is that there is a 2 inch wide strip of unpainted bumper, therefore NO RISK OF DAMAGING PAINT! I just used double sided tape again to attach the coroplast.

It kinda looks like teeth

Coroplast lines up perfectly to sit flush with the bumper

Building the fog light covers:
I just used painters tape and masked the fog light covers. Then took a pen to trace the shape onto the tape. Then i took the tape off and put it on corolast, then cut to shape. Attached using double sided tape.

it sits flush

Finished the grill block and PAINT

If you're wondering what type of paint i used for the bumper...its' flat black PLASTIDIP....i sprayed the bumper to protect against rock chips because a 3m clear bra would run me $650 :eek: The nice thing about Plastidip is that it will peel right off if i ever want to change color or touch it up.

Pseduo Results: the car seems to coast a lot longer now, no ABA testing because i know these mods definately worked on my del sol. EPA is 20mpg combined...right now im averaging about 23-24 mpg combined. The car is still breaking in with only about 1300 miles on it. MPG's should hopefully increase after my first oil change.

Next up: upper grill block and side skirts

My dog, Einstein, checking out the new ride

**Updates 8/12/13**
Building the Side Skirts - I didnt want to drill into body work, luckily the bottom of the car is already flat from the factory, so i want to build something that is lighweight and that i can attach using double sided tape. A traditional vinyl rain gutter felt a bit too heavy to be supported by double sided tape. I also wanted to make it easily removeable for ABA testing.

**UPDATES The side Skirts ended up warping and looking really crappy. REMOVED SIDE SKIRTS 8/26/2013**

Building the upper grill block
The hoodline creates a big gap, so i want the upper grill to serve a double purpose....cover the grill and cover the hood gap. I'll most likely use velcro so i can remove the block easily.

Using painters tape to see how much blockage i can get away in terms of engine temps. So far, engine temps have been normal around 188*F

Rough fitment and Mockup - i'll tweak this design if I ever have any engine temp issues.

**Added 8/26/2013** See Page 6 for more details

**ADDED 8/26/2013** Kill Switch V. 2.0 - Page 6

**ADDED 9/13/13** upper grill block v3.0 - Page 7
**ADDED 9/23/13** passenger side mirror delete - page 8

**ADDED 10/11/13** Kill Switch V. 2.1 - replaced with brake switch- Page 11

**ADDED 10/11/13** Lower Grill Block v1.1 - One Solid coroplast piece- Page 11

**ADDED 10/16/13** Upper Grill Block v331 completed - page 12

**ADDED 1/15/14** underbelly tray - page 12
Front to rear

rear under tray with rear wheel boat tails

***ADDED 3/20/14 scangauge ii*** Page 14

***ADDED 4/30/2014 Upper Grill block v3.4*** page 17

***ADDED 6/28/14 Underbelly tray v2.0*** page 22

***ADDED 8/30/2014 Windows Tinted*** page 25

***ADDED 8/30/2014 Rear Diffuser*** page 25

***ADDED 10/6/2014 Almost OEM Upper Grill Block page 26*** page 25

***ADDED 11/3/2014 Almost OEM Lower Grill Block*** page 26

ksa8907 08-07-2013 09:58 PM

Nice car! I'm just curious about "protecting" the bumper.... but you would have to repaint it right?

jedi_sol 08-07-2013 10:03 PM


Originally Posted by ksa8907 (Post 384087)
Nice car! I'm just curious about "protecting" the bumper.... but you would have to repaint it right?

The paint is called "PLASTIDIP," its an aerosolized rubber paint. The nice thing about it, is that it peels right off if i want to change colors or touch it up. There are about 6-7 coats on there. I can see a few places where rocks must have grazed the paint. The Plastidip was not even phased!

Check out:

vskid3 08-07-2013 10:41 PM

I thought you'd lost your mind when I saw the painted bumper. I quickly scanned the next paragraph, hoping to see "Plastidip".
Nice idea sticking the blindspot mirror on the folded mirror. I'll have to see if I can find a good spot for some coast down tests and see how much it could help my Prius.
Looks like a fun car. I would have a hard time even thinking about driving it efficiently.:thumbup:

jedi_sol 08-07-2013 10:49 PM

Yeah, don't worry everybody. Plasitdip peels right off!

They also make a clear plasitdip, but I'd have to order it in bulk because home depot/wal-mart only carry black and white.

jedi_sol 08-08-2013 03:35 PM

Jdm aero
I found some JDM aero parts as inspriation (thanks Hockey3592).

Aero Mirrors - $839 :eek: made from Carbon Fiber...I'm sure i can copy this with some leftover coroplast and fiberglass

Aero Antenna - S-Craft $59 sure i can do this for less than $59...but are the benefits worth all of the time and effort to make this?

Subaru OEM Underbody trays - $75ish That's more like it!

Or i can go fancy with aluminum - Laile - $336

Or i can do Aluminum bars/home depot/screws/coroplast - $40 :thumbup:

kaiba 08-09-2013 04:33 PM

Hypermilling/ecomodding a STI, now that's something you don't see everyday.

jedi_sol 08-09-2013 04:41 PM


Originally Posted by kaiba (Post 384394)
Hypermilling/ecomodding a STI, now that's something you don't see everyday.

I'm blazing trails :turtle:

a lot of things tuners do to make their car faster can also apply to ecomodding (ie aero parts).

Apparently, the stock tune from Subaru runs a bit on the rich side. Cobb Tuning makes a thing called "accessport" that allows me to change the ecu tuning on the fly. People say the basic off the shelf Cobb tune, they gain 40hp right off the bat plus an extra 3mpg without altering driving style(and these are people that already drive the car aggressively). I imagine i can squeeze more than 3mpg with that kind of tool

However, it costs $650...with the amount of miles i drive everyday, the payback period would be 15,000miles depending on how long i keep the car, it may or may not be worth it.

UltArc 08-09-2013 06:37 PM

Looking good! I didn't think it would be long before you got back into it!

It's also nice to see another newer performance oriented vehicle. Have you setup your kill switch yet? That may not show you as great of gains as it did me, 2.5 idling isn't as bad as 3.7. It's nice Subaru has real underbody panels, even if they aren't what you exactly want- it at least gives a nice platform to build off. Glad you got started, and I look forward to following.

Awd180 08-09-2013 07:02 PM

I have an 02 wrx wagon, avg 32mpg could do better but it needs to be driven.

lw crank and alt pulley, silcon intake and ic hoses, tbe, oil air separator, no a/c belt
heat wrapping (hood, turbo and tmic, down pipe is next)
I'm going to have my suspension upgraded next
then I have header already heat wrapped I'm waiting to put on
dunlop star specs summer (winter cheap tires)

good luck with your modding, and no matter how much you mod once you hit boost your mpg's go down.

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