Mel got a Subaru!

[nobuffalo]

This may seem like a silly question, but what are you trying to achieve by adding power?

 

[ITCC_Andrew]

if it lines up with your air intake then go for it,

I'm thinking custom fab. I've got my ways. The hood and intake manifold line up; that's why the STi has the intercooler on top; it's easier, an the rocks don't hit the intercooler. It also (conveniently) draws in more air through shorter piping, into the intercooler/intake manifold.

This may seem like a silly question, but what are you trying to achieve by adding power?

Autocross; for 2013, I'm in stock or Road Tire All-wheel-drive class. But, for 2014, I'm getting tired of the 205/55/16 tires. The aspect ratio is ugly.


So, since I'm changing tire size, and rim size, I'll be in a modified class, pending upgrades. Preferably, I'll get 200+ hp, with a really great handling/looking package. So, yeah. I'm really planning on going bigger in the future. I'll have a huge budget, since my parents are giving me a house (upon passing,) and employment will be steady, and good-paying.

 

[Mike Rotch]

*Moving to Member Rides section*

 

[ITCC_Andrew]

*Moving to Member Rides section*

Was it supposed to be there the whole time? I trust your discretion.

 

[Mike Rotch]

No - but since you have now bought a car, it does belong here, along with all the other threads of members and their automobiles.

 

[ITCC_Andrew]

No - but since you have now bought a car, it does belong here, along with all the other threads of members and their automobiles.

Oh yeah!


Also, Bam!

 

[ITCC_Andrew]

Hey guys,


Does anyone know how to keep water out of the engine bay with a WRX STi hood? How doesn't water just fall into the intercooler?


Canada's "water" happens to be "slush." For those of you from Australia, or whichever other "warm" place, "slush" is a mixture of snow and ice, that's melting, with a highly corrosive thing called "salt" in it... Machines called "ploughs" put the salt down, and the snow and ice magically melt into slush. Ice is slippery, you know, right? Right Dave?


P.S., I'm not a pelican, I'm a baboon.


Anyways, I don't want to let water/slush into the engine bay, when I get my carbon hood, etc. So, I'm planning. The water/slush would rust/destroy the internals of the engine (manifolds, muffler, cylinder block...) Through acid corrosion (salt.)

 

[Punknoodle]

Hey guys,

Does anyone know how to keep water out of the engine bay with a WRX STi hood? How doesn't water just fall into the intercooler?

Canada's "water" happens to be "slush." For those of you from Australia, or whichever other "warm" place, "slush" is a mixture of snow and ice, that's melting, with a highly corrosive thing called "salt" in it... Machines called "ploughs" put the salt down, and the snow and ice magically melt into slush. Ice is slippery, you know, right? Right Dave?

P.S., I'm not a pelican, I'm a baboon.

Anyways, I don't want to let water/slush into the engine bay, when I get my carbon hood, etc. So, I'm planning. The water/slush would rust/destroy the internals of the engine (manifolds, muffler, cylinder block...) Through acid corrosion (salt.)

Well normally there is an intercooler under there , which pretty much seals it up and air flows through it. If you don't have an intercooler then ya, it's pointless having a scoop and you will get water in there. You could seal the bottom of the scoop.

 

[Murcie_LP640]

If you don't have an intercooler then ya, it's pointless having a scoop and you will get water in there. You could seal the bottom of the scoop.

Mhm, seal it or don't get a hood with a scoop.

Even with an intercooler though you'd probably have to watch for salt corrosion as well.

 

[ITCC_Andrew]

Point is, right now, I can feel the latency in the RPMs, from the air intake, and the four feet of plumbing it has to flow through. The intake manifold is directly below where the intercooler would normally sit. 💡 In the case of wanting a better fuel burn, (through ECU) and shorter intake piping, making the air travel the shortest distance possible is a win-win situation. Sure, I bet you can find plenty of *decent* air intakes, but... I'm going to need a new hood, anyways. Why not try to make a proper, air-tight, extremely short air-intake, while I'm at it?


Understand, though, that I have an almost unlimited amount of supplies, contacts, and a decent amount of space, because I work in a huge factory, that makes everything from solar panels to saw blades, and even "logger/gatherers."


P.S., you wanna see what my dad and I build? "Tigercar L880" in google images will bring you up-close and personal with the fruits of the labour of our entire "team."

 

[Punknoodle]

Well it sounds like you already have it sorted...

And your engine is a small naturally aspirated unit. I seriously doubt you can 'feel' the effects of the intake plumbing - more the fact that they just aren't that quick..

 

[nobuffalo]

If you're afraid of water/slush getting in through the scoop and causing damage to the exterior of the engine what makes you think a fully sealed scoop with only an inlet for the intake is gonna be any better?

Also, I won't even claim to know what I'm talking about but something tells me having air flow through the shortest distance isn't always the best setup for an intake.

Also there's nothing on your hood a little sanding and painting wouldn't fix, you don't need a new carbon fiber STI one.

edit: I'm a little confused at your intent with a STI hood with the scoop, are you wanting to use the scoop to get cool air to the intake or do you just want it for looks?

 

[ITCC_Andrew]

If you're afraid of water/slush getting in through the scoop and causing damage to the exterior of the engine what makes you think a fully sealed scoop with only an inlet for the intake is gonna be any better?

Also, I won't even claim to know what I'm talking about but something tells me having air flow through the shortest distance isn't always the best setup for an intake.

Also there's nothing on your hood a little sanding and painting wouldn't fix, you don't need a new carbon fiber STI one.

edit: I'm a little confused at your intent with a STI hood with the scoop, are you wanting to use the scoop to get cool air to the intake or do you just want it for looks?

You remember that I plan on autocrossing it, correct? And that a carbon fiber hood will be lighter, right? As the current intake is set up, it's routed THROUGH the fender, on the passenger side. Why the hell?!

 

[GDII]

I think trying to make your intake shorter will end up not working so well in the long run. If it rains or 'slush' gets into the hood scoop, your engine will just ingest it and end up being very unhappy. I have kept the stock intake piping on my NA MR2 because of this very reason. The stock piping has places for the water to drain out before it gets to the engine.

I say good on you for making an effort to get out and do autocross but extra power isn't always the way to win or even have a lot of fun. In my first Autocross I placed 7th out of 30 drivers. Only mod to the car was a Simota panel filter in the standard air box but that was full of dust so probably reduced performance. I was beating purpose built cars and I had never driven the car on grass before.

Make the car handle better and make it lighter. Yes a carbon bonnet is lighter but at what cost?

 

[Murcie_LP640]

You remember that I plan on autocrossing it, correct? And that a carbon fiber hood will be lighter, right? As the current intake is set up, it's routed THROUGH the fender, on the passenger side. Why the hell?!

His concern, and mine for that matter, is not with the carbon fiber hood, it's the carbon fiber hood with a scoop. All that scoop is going to do is allow slush to get into your engine bay easier; even if it did give you a slight, and it would be slight, performance increase, it ain't worth the risk!

 

[Punknoodle]

^This. I don't doubt you can make some kind of induction from the scoop, incorporate a filter somewhere, but the chances of it getting soaked up with crap is high and frankly, I think it's gonna do stuff all for performance anyway.

So, it comes down to looks. Personally when I see non WRX's sporting scoops I think both it and the owner are silly. If you really want one though, think of a way to blank off the bottom of it. It's gonna fill up with stuff and need cleaned out but at least it won't rust and it's better than having it cover your engine..

 

[Punknoodle]

One more thing, having a scoop channeling air from above the car to under it will cause lift at speed. It's probably marginal but you don't see scoops on race cars without purpose, do you?

Now that I'm running a charge cooler as opposed to a top mount air to air cooler I am on the lookout for a Group A bonnet which has a vent as opposed to a scoop, this lets warm air flow out rather than having more air enter the engine bay from ineffective places, causing minor lift and slightly effecting air flow through the front of the car, where you want the air to flow fast in order to cool the radiator and heat exchanger for the charge cooler..

We aren't talking massive effects here but just thought I'd mention it.

 

[Crash]

Does anyone know how to keep water out of the engine bay with a WRX STi hood? How doesn't water just fall into the intercooler?

The hood is sloped, which obviously helps water roll down the hood instead of into the intake, however there will be some that will get in. The little bit that does get in typically gets evaporated very quickly since the engine compartment is pretty hot. If you're worried about slush falling in, then the only way is to seal the intake shut.

But then there are plenty of other places where water will get into your engine compartment. A little bit of rust is ok on the exhaust manifold, it's fairly normal.

Where are you going to fit an air filter, or are you going to run without run? Is there even space between the hood and the engine to fit an air intake?

If you're afraid of water/slush getting in through the scoop and causing damage to the exterior of the engine what makes you think a fully sealed scoop with only an inlet for the intake is gonna be any better?

Also, I won't even claim to know what I'm talking about but something tells me having air flow through the shortest distance isn't always the best setup for an intake.

Correct. Shorter intake isn't necessarily worst, but it's not automatically better either.

Point is, right now, I can feel the latency in the RPMs, from the air intake, and the four feet of plumbing it has to flow through. The intake manifold is directly below where the intercooler would normally sit. 💡 In the case of wanting a better fuel burn, (through ECU) and shorter intake piping, making the air travel the shortest distance possible is a win-win situation. Sure, I bet you can find plenty of *decent* air intakes, but... I'm going to need a new hood, anyways. Why not try to make a proper, air-tight, extremely short air-intake, while I'm at it?

What? This doesn't make sense. Better fuel burn is affected by a bunch of different parameters; ECU tuning is dependent on the physical properties of your engine (fuel delivery, air delivery, spark, compression, etc.). Though ECU tuning can certainly affect fuel burn, if you completely screw up one of the physical properties, no amount of ECU tuning can compensate/fix it.

Also, shorter air intake is not necessarily better. First off, it is not a vacuum outside of (or before) the throttle. There is still air in the piping, so it doesn't really matter if the intake piping distance is longer or shorter. One of the things that actually highly affects throttle response is the distance between the throttle and the combustion chamber, since that does affect the travel time of incoming air. There are also other variables that will affect throttle response like intake manifold volume and shape, along with throttle type and shape and manufacturing tolerances.

To increase power, if I remember correctly (and a fluid dynamics and engine specialist jump in here to correct me), you want to maximize laminar flow of the incoming air in the intake piping. Once the air gets to the intake manifold, you want to have turbulent airflow. (I recognize that there is friction from the intake piping walls, thus perfectly laminar flow is impossible, but let's ignore the effects of friction for now.) Laminar flow in the piping is important to help maximize the velocity of the airflow, thus allowing more air into the engine, and allowing a bigger bang. With that said, it's more important for your intake to be in the path of clean air instead of dirty air. Placing your intake in dirty air is just going to wreak havoc on the available flow of air into your intake due to the turbulent air around your intake.

Another thing with fluids is that it doesn't like to make sharp turns. A longer intake pipe can help you smooth out the kinks and corners in such a way to help the air stay as laminar as possible. Having a short intake pipe often won't give you as much flexibility in ensuring smooth airflow path while maintaining easy packaging. In fact, for the air to flow from the hood scoop to the current intake will probably require you to route something that has a couple of small radius U-turns in it, which will likely restrict your airflow even more than the stock setup.

If you want to learn more about how air flows in an engine and how various parameters will affect throttle response and power, I highly recommend that you google some of the things I talked about above. It makes for quite an interesting read.

 

[ITCC_Andrew]

So, if I were to get a really good air filter, (or just use the replacement my dad bought recently...) That would be decent?


What then, do you think is causing the throttle latency, Crash? I'm lost. I know it's fly-by-wire throttle input, so it'll be slower, but... Darn, I want to have a little more go up to the same redline (no, I don't want to mess with engine internals until 2014, at least.)


Also, I'm really starting to regret buying the automatic. Is there a way to redline-launch with an automatic? I'm a bit "timid" of holding the brakes and throttle at the same time, without a clutch pedal.


So, what are my options, in order to launch at redline...? The AWD doesn't get much wheelspin, so grip isn't hard to find.

 

[Korza]

Also, I'm really starting to regret buying the automatic. Is there a way to redline-launch with an automatic? I'm a bit "timid" of holding the brakes and throttle at the same time, without a clutch pedal.


So, what are my options, in order to launch at redline...? The AWD doesn't get much wheelspin, so grip isn't hard to find.

What are you going to gain from a redline launch in an automatic family wagon other than unnecessary stress on your engine and gearbox?

 

[Punknoodle]

Are you comparing your throttle response to an identical car or is it just your opinion? It isn't a Ferrari, mate, its an economical Subaru N/A engine, it was never designed to have snappy throttle response. If, however, you have noticed that it has poor throttle response compared to an identical one it could be poor ignition timing, clogged injectors, poor fuel, poor spark plugs...

Subaru spent a lot of money developing the intake that is on there at the moment. In 95% of applications a high flow air filter in the standard intake is just as good if not better than a custom intake..

By the way, the whole slushbox thing is never going to help with acceleration. You are trying to make a non sports car in to a race car.. It's not going to live up to your expectations I'm afraid..

 

[ITCC_Andrew]

What are you going to gain from a redline launch in an automatic family wagon other than unnecessary stress on your engine and gearbox?

- A hard launch, not a stereotypical "grandpa" voice.

Are you comparing your throttle response to an identical car or is it just your opinion? It isn't a Ferrari, mate, its an economical Subaru N/A engine, it was never designed to have snappy throttle response. If, however, you have noticed that it has poor throttle response compared to an identical one it could be poor ignition timing, clogged injectors, poor fuel, poor spark plugs...

Subaru spent a lot of money developing the intake that is on there at the moment. In 95% of applications a high flow air filter in the standard intake is just as good if not better than a custom intake..

By the way, the whole slushbox thing is never going to help with acceleration. You are trying to make a non sports car in to a race car.. It's not going to live up to your expectations I'm afraid..

I'm comparing the throttle response to that of a Hyunmdai Accent, actually. I think it's the transmission, really, because it does rev somewhat quickly, just... The revs don't immediately always translate into speed, unless the car is already in a low gear.

 

[Punknoodle]

Well yeah... That's your transmission. Stuck with that, I'm afraid.

 

[Murcie_LP640]

Transmission, combined with a relatively low torque output that peaks high in the rev range. Torque's always been the issue with NA Subarus; the EJ25 rectified it a fair bit but NAs will still feel lethargic.

Same story with my Accord. The manual helped acceleration a bit but you had to give it the beans to actually get anywhere on hills at a semi-decent pace.

The EJ253 has more power and torque than the ol' F22B1 but again it comes round to the automatic transmission making the difference redundant.

tl;dr: Small atmo 4-cylinder with a slushbox. Not much to expect from it really.

 

[ITCC_Andrew]

Well, I talked to my tech teacher... Until 2014, there isn't any other upgrade I can do.


However, I've got more photos.

 

[GDII]

What is your experience in Autocross? There isn't much point modifying the car until you know how to drive it. To be fast you need to get the car to change direction quickly and stop fast. Power should just be an after thought.

I did a hillclimb and I only beat my brothers 1300cc Toyota Starlet by 1 second because my car had more power. My corner speeds were so much slower, because of inexperience and a heavier car.

 

[ITCC_Andrew]

I completed a full year of TLMC autocross.


I learned a lot last year, but, this year, I'm bringing a car, that's in top-performing shape, to match with the driving aspect... Because, no matter how good the driver... A Hyundai Accent can't beat a 500 hp alcohol injected Impreza (there was one, last season.)

 

[Korza]

And you think a NA automatic Impreza wagon will?

 

[McLaren]

Well normally there is an intercooler under there , which pretty much seals it up and air flows through it. If you don't have an intercooler then ya, it's pointless having a scoop and you will get water in there. You could seal the bottom of the scoop.

If you seal the bottom of the scoop, what becomes the point of it then? You're not letting in air into the engine bay if it has no way to get to it through the scoop. Sounds to me like it becomes purely for show. Sealing it except for a section for the intake sounds like an even worse idea; the only place for the air and the slush is in the intake then. At least, that's what I'm reading.

In short, OP might as well forget the point of having an STi hood at all. A CF one isn't going to make any significant difference, either.

Understand, though, that I have an almost unlimited amount of supplies, contacts, and a decent amount of space, because I work in a huge factory, that makes everything from solar panels to saw blades, and even "logger/gatherers."


P.S., you wanna see what my dad and I build? "Tigercar L880" in google images will bring you up-close and personal with the fruits of the labour of our entire "team."

I was wondering when this little tidbit would come up; it always does in these types of threads when members point out the various barricades that an owner will face with what he wants to do with his car, but that same person always has a way around it because of his vast skills, money, work, etc.

It comes to a point of why you bother even asking us anything. Any time someone responds, you seem to already have a solution to your problem....

BTW, I googled & got a giant amount of images that tells us nothing.

I learned a lot last year, but, this year, I'm bringing a car, that's in top-performing shape, to match with the driving aspect... Because, no matter how good the driver... A Hyundai Accent can't beat a 500 hp alcohol injected Impreza (there was one, last season.)

Here's your issue. You're comparing this basically stock Subaru Impreza to an Accent (lawd....), & then talking about that you'll be auto-crossing the Impreza with a 500Hp build.

That's a huge leap in power for a driver, & chances are high that yes, a very good, years of experience driver with an Accent probably could beat someone whose brought a (dreamed up for now) 500Hp Impreza with little experience in it with the extra mods.

I think you're giving yourself too much credit & too high expectations for how you want this car to perform.

 

[ITCC_Andrew]

Holy 🤬, McLaren. Do you read anything? Or, are you really just inclined to misread, misinterpret, and make inaccurate conclusions?


I didn't say that I'm going to do the hood scoop, anymore. Instead, I said 🤬 it, and stop coming here to complain about me. Go get a wfie, or something. Maybe she'll hear your complaints.


I did, however, say that, last year, there was a guy with a 500 hp Impreza. Did I say I wanted his ugly 500 hp Impreza? NO! Read more carefully, please.


Fact is, I'm trying to make my car as efficient as possible, in SCCA Solo2 G-Stock trim. I want to make it as fast as possible, for my class. Then, when I can, I'll work with the biological, squidgy, fleshy bit behind the wheel, once my car and I can both be at the top of our game.


I'm preparing for a championship, for 2013. I'm planning my upgrades for 2014, when I'll step up to a higher class, with better rims, tires, suspension, and brakes...


What don't you understand? I'm trying to compete. I'm trying to win. I want to take a gun to a gunfight, instead of always coming up short.


Yeah, sure, I'm not an SAS squad leader, but, that doesn't mean I can't bring a weapon worth carrying, does it?

Now, relate back to cars; I'm bringing a car at the top of its potential, because I want to have a car, that's ready for what I'm trying to throw at it.


I'd prefer if you took your cynical, snide remarks elsewhere, and tried to help, instead.