2013 WRX - Modding/Tuning

[rg200amp]

I have been toying with the idea of having this car has a "fun" car and I have decided to go over the top nutty with it.

I am having it tuned (with Cobb) as well as modifying it a bit with intake, exhaust, light weight pulley, and new inter-cooler.

As such, warranty is no longer a concern. So oil choice has expanded!


I plan on running either Redline or Motul 5w40 in it.

However, I was able to pick a few cans of this "stuff", and I think it will come in handy while dyno tuning this beast over the summer:

I also plan on changing out the diff's and tranny fluid to either Redline or Motul. (still researching and pondering what to go with long term)

The performance shop that I have been speaking with has a lot of experience with Subaru and they all drive WRX's and STi's. From doing my own research and from speaking with them, I am looking at breaking 325+ horsepower. I am going to need to begin converting the fuel pump/injectors and internal parts such as pistons beyond that to keep up. . .

For those wondering, I am planning on buying a low mileage, early 2000's Audi A4 for a "daily driver".

 

[sciphi]

A tune and intake/exhaust isn't nutty at all. That's mainstream for a tuned car. Nutty is making it bonkers enough to frag diffs on demand!

The problem with making it bonkers is keeping enough sanity in it where it's still fun to drive. I've been in my manager's '12 WRX that's quite the aural treat driving by. It wasn't so great taking it for a spin, since the cabin was so loud that it almost hurt.

 

[artificialist]

Ever since I saw a Subaru get a FMIC, I wanted somebody to connect the ram air hood to the engine air intake. I have never seen it done. Instead, I just see people use the ordinary "Cold air intakes" which don't always draw in cold air.

Ever consider building such and air intake?

 

[gathermewool]

This will be a dedicated track/rally car or just a fun weekend car?

Are you planning on having it professionally tuned or using one of Cobb's off-the-shelf (OTS) maps? There's nothing wrong with the OTS maps - I Cobb stage 1 now - but pay attention to the map notes with regard to the required mods. In other words, only use intakes that Cobb has a map for, and downpipes(DP) with a high-flow cat installed, not any old "race/test/straighr/catless" DP.

I'd skip the lightweight pulley - what're you trying to accomplish here? If it's a slight gain in acceleration, then you should look elsewhere. Besides, a stage 2 (catted DP and protune) will sufficiently put you back in your seat, such that the addition of a pulley won't be noticed...unless it causes issues.

Exotic fluids are ok, but the tried and true for these motors are M1 0W-40, German Castrol 0W-30, and Shell Rotella T6 5W-40. The 300V will do just fine, as will any other true synthetic oil, but it's by no means necessary. If money is no object, then by all means, however. I've contemplated going all out with some Renewable Lubes, but it's just so darned expensive and seemingly unnecessary.

For the gears, Motul Gear 300 is great, but so too are most of the other offerings.

 

[sciphi]

Originally Posted By: artificialist
Ever since I saw a Subaru get a FMIC, I wanted somebody to connect the ram air hood to the engine air intake. I have never seen it done. Instead, I just see people use the ordinary "Cold air intakes" which don't always draw in cold air.

Ever consider building such and air intake?


Another reason to use a true CAI, even on a turbo setup, is to lower the temperature of the air the turbo has to pressurize. Then the FMIC won't need to work as hard shedding heat since the air is that much cooler to start, and won't need as much pressure to get the same effect. Less boost = less heat. All the rubber parts in the engine bay will be happier from less extra heat, the engine cooling system won't work as hard overcoming the heat boiling off the FMIC ahead of the radiator, and the turbo will not work quite as hard. Win-win.

 

[rg200amp]

Originally Posted By: gathermewool
This will be a dedicated track/rally car or just a fun weekend car?

Are you planning on having it professionally tuned or using one of Cobb's off-the-shelf (OTS) maps? There's nothing wrong with the OTS maps - I Cobb stage 1 now - but pay attention to the map notes with regard to the required mods. In other words, only use intakes that Cobb has a map for, and downpipes(DP) with a high-flow cat installed, not any old "race/test/straighr/catless" DP.

I'd skip the lightweight pulley - what're you trying to accomplish here? If it's a slight gain in acceleration, then you should look elsewhere. Besides, a stage 2 (catted DP and protune) will sufficiently put you back in your seat, such that the addition of a pulley won't be noticed...unless it causes issues.

Exotic fluids are ok, but the tried and true for these motors are M1 0W-40, German Castrol 0W-30, and Shell Rotella T6 5W-40. The 300V will do just fine, as will any other true synthetic oil, but it's by no means necessary. If money is no object, then by all means, however. I've contemplated going all out with some Renewable Lubes, but it's just so darned expensive and seemingly unnecessary.

For the gears, Motul Gear 300 is great, but so too are most of the other offerings.


1. Weekday+Weekend fun car as well as a light touch of autocross.

2. I am having a professional tune it that uses the Cobb. They do open source tunes as well, however are much more impressed with Cobb's offering and results.

3. Pulley is a cheap CHEAP addition. It improves throttle response ever so slightly and nothing else.

4. DP and stage 2 will be a fall/winter project in addition to wheels+tires.

5. Oil is a low cost expense. Saving $20 is not a factor. The professional I have talked with personally runs 300V in his cars. However, he also like the 8100 Motul line. He buys drums of the 8100 to perform oil changes on may of his customers cars and is happy with it's results. That is one reason why I am leaning towards it.

6. Gear 300V is where I am leaning to!

 

[gathermewool]

Originally Posted By: artificialist
Ever since I saw a Subaru get a FMIC, I wanted somebody to connect the ram air hood to the engine air intake. I have never seen it done. Instead, I just see people use the ordinary "Cold air intakes" which don't always draw in cold air.

Ever consider building such and air intake?


That would partially defeat the point of the FMIC, since HOT air from the motor would be pouring out of the hood scoop while stationary, causing whatever connection was fabricated to adapt the scoop for intake purposes to heat up the air.

It would then be compressed and pumped through the FMIC, but, while stationary, it wouldn't cool the air as effectively as if the intake were routed to the front fender.

Also, the bends to go from the scoop to the turbo, then back to the FMIC would be heinous, and difficult, if not impossible to route.

Some who go FMIC block off the scoop or reverse the scoop in an effort to draw more air through the engine compartment, and also through the FMIC. I'm not sure the actual effectiveness of either.

 

[rg200amp]

Originally Posted By: artificialist
Ever since I saw a Subaru get a FMIC, I wanted somebody to connect the ram air hood to the engine air intake. I have never seen it done. Instead, I just see people use the ordinary "Cold air intakes" which don't always draw in cold air.

Ever consider building such and air intake?


I plan on keeping a TMIC. I am going to go with a Perrin. I also plan on fitting a water sprayer to cool it down when heat soaked.

 

[gathermewool]

Skip the pulley and wait to professionally tune until you're ready to go stage 2. Unless your tuner is willing to cut you a deal (Stage 1 now, 2 later,) an OTS stage 1 tune is a pretty good starting point.

It'll also give you time to figure out how to log and properly monitor the health of your engine - a baseline, so to speak. You can swap between the 93 and 91 octane maps if you see some cruise (phantom) knock, and ensure you've got a healthy motor before upping the risk or noticing problems for which only your tuner will have answers. YOU should know your engine and its tune, and not be reliant upon others to ensure your motor isn't going to blow up.

Going in stages will save you some money, but it will also give you time to process and enjoy the changes. I feel the same way about suspension mods. Check out some sways, then maybe some springs by companies known to match the OEM dampers (not just those who want to SLAM it,) and then go to coilovers if you're still not satisfied.

If you're experienced in either engine or suspension tuning, then I apologize for possibly condescending, but start slow. The '13 Rex is a beast out of the box. No need do more than up the power and performance step-wise until you're satisfied.

FWIW, I bought my '08 new and thought I'd be well beyond stage 2 by this time (60k miles,) but stage 1 really was all I needed. When my warranty is up I might consider going further, but while my car has aged, so too have I, and now spending thousands on a car that is already very capable just doesn't seem as appealing as it did four years ago...

If you have any questions, please don't hesitate to PM me. I may not remember the answer, but I'll surely help you find one if I can!

 

[rg200amp]

Originally Posted By: gathermewool
Skip the pulley and wait to professionally tune until you're ready to go stage 2. Unless your tuner is willing to cut you a deal (Stage 1 now, 2 later,) an OTS stage 1 tune is a pretty good starting point.

It'll also give you time to figure out how to log and properly monitor the health of your engine - a baseline, so to speak. You can swap between the 93 and 91 octane maps if you see some cruise (phantom) knock, and ensure you've got a healthy motor before upping the risk or noticing problems for which only your tuner will have answers. YOU should know your engine and its tune, and not be reliant upon others to ensure your motor isn't going to blow up.

Going in stages will save you some money, but it will also give you time to process and enjoy the changes. I feel the same way about suspension mods. Check out some sways, then maybe some springs by companies known to match the OEM dampers (not just those who want to SLAM it,) and then go to coilovers if you're still not satisfied.

If you're experienced in either engine or suspension tuning, then I apologize for possibly condescending, but start slow. The '13 Rex is a beast out of the box. No need do more than up the power and performance step-wise until you're satisfied.

FWIW, I bought my '08 new and thought I'd be well beyond stage 2 by this time (60k miles,) but stage 1 really was all I needed. When my warranty is up I might consider going further, but while my car has aged, so too have I, and now spending thousands on a car that is already very capable just doesn't seem as appealing as it did four years ago...

If you have any questions, please don't hesitate to PM me. I may not remember the answer, but I'll surely help you find one if I can!


Thanks for the info. I am aware of a lot of this but will keep ya in mind for any Q's.


What's your beef with the Pulley? The Cobb pulley is the same size, only weighs 4+ pounds less. It is a fool proof, risk proof item that has a real (however slight) improved throttle response.

 

[Mykl]

I know this thread is mostly about engine performance, but don't forget about the suspension. A pair of upsized anti-roll bars make all the difference with these cars as the increased roll resistance mitigates camber loss while cornering, increasing overall grip. I know the car has a lot of wheel gap, but do try to resist the urge to slam it; the car needs every bit of that bump travel to maintain good grip up front during trail braking.

Also try to dial in as much negative camber up front as you can get. I found about 2.5 to be ideal, although this won't be achievable without plates.

For the engine I would stick to the tried and true; exhaust and a tune, then intercooler and intake. A pulley isn't going to give you enough to be worth the effort/risk.

 

[gathermewool]

I wouldn't say swapping the pulley is full proof, but you're right, the risk is low. If you happen to experience any adverse effects, you can simply swap the stock one back in.

I don't ever mean to talk down to people, but most people who have issues after modifying their Subie are the same who were generally aware of all of the precautions I mentioned, but no explicitly so. In other words, they think to themselves, "yea, yea, research, buy, log the ECM, and repeat," but many times the justification is made to skip the research and logging part, because their tuner said it's good to go, and that they now have a SUUUUUUPER conservative tune.

What I'm trying to say is, trust but verify. You can trust what people like me tell you on the interwebs, but verify with your own research and logging. Logging aggressively initially and periodically there after is 100% required for light mods, and aggressively all the time for heavy mods. One, two, three, 1,000 good knock events, and you've smoked your piston ring, spun a bearing or machined your turbo into an expensive paper weight.

If you haven't already, there are many good WRX/STI enthusiast sights to ask questions of people WAY more knowledgeable than me. I moderate one, and really only peruse the others. If you're not sure which I'm talking about, PM me for more info.

 

[SteveSRT8]

Of the 3 WRX enthusiasts I know locally only one has kept his original motor together. His is nearly stock. I was present when one exploded at only 22k miles!

If you tune them aggressively you need to understand that they can become a smoking paperweight in seconds as almost any forced induction car can if there is the slightest malfunction. This is not a knock on Subies, just a warning that playing can be costly. My advice is check your bank account, if you don't have the 5 grand (or more!)you'll need for a proper rebuild then this may not be the playground for you.

Note also that the 450 hp model that can SMOKE me from a stop can't even stay close from a 60 mph roll!

 

[sciphi]

Originally Posted By: gathermewool

I don't ever mean to talk down to people, but most people who have issues after modifying their Subie are the same who were generally aware of all of the precautions I mentioned, but no explicitly so. In other words, they think to themselves, "yea, yea, research, buy, log the ECM, and repeat," but many times the justification is made to skip the research and logging part, because their tuner said it's good to go, and that they now have a SUUUUUUPER conservative tune.


Agreed, the biggest part is logging after each mod, and periodically. I have a customized tune with less peak boost and raised timing on my Cruze, and it took 3 logging sessions to get a tune the tuner was satisfied with. I'll datalog it again this summer to make sure it's still fine. We had somebody blow their Cruze's engine after running at WOT for extended periods of time because they threw the tune into the PCM and didn't bother datalogging since they assumed it was good to go.

 

[oggb]

Lightweight pulley: The pedal lag from the drive-by-wire on my '06 WRX was very annoying, and I know a few folks that have installed these. They're about 50/50 as to whether they've noticed a difference.

Mods: Your '13 WRX will break 300 WHP at Stage II. Past 300 WHP you're probably going to be sacrificing reliability.

Oil: Redline 40-weights are great. So are Motuls. It's a toss-up, really.

 

[oggb]

Originally Posted By: sciphi
I have a customized tune with less peak boost and raised timing on my Cruze


lolwut

Seriously, please elaborate. I'm very interested in hearing about this.

 

[sciphi]

Originally Posted By: JRed
Originally Posted By: sciphi
I have a customized tune with less peak boost and raised timing on my Cruze


lolwut

Seriously, please elaborate. I'm very interested in hearing about this.


I'll PM you details so not to derail this.

 

[SteveSRT8]

Yeah, my tuner at Diablosport will tweak their tune any way you want. Cost is minimal and all you do is email logs back and forth.

it's so easy even a dinosaur can do it (like me!).

 

[gathermewool]

Originally Posted By: JRed
Originally Posted By: sciphi
I have a customized tune with less peak boost and raised timing on my Cruze


lolwut

Seriously, please elaborate. I'm very interested in hearing about this.


What's with the "lolwut"? Do you know anything about tuning?

 

[rjundi]

I do know a few owners of Subaru turbo's(Legacy GT) with 150k+ and at Stage II which tune + exhaust (gutted down/up pipes and new cat back exhaust). They were "conservatively" tuned.

They also drive normally and enjoy the power occasionally. My wife has a pure stock 2.5L turbo motor with 5mt she occasionally winds to 5500 RPM on the highway. We are running trouble free over 150,000 miles with regards to motor. 3500 miles dino oil changes to boot(the horrors

) I think people just get stupid but I guess part of growing up.