GrimmSpeed 05-09 LGT Intake - Any Interest?

[quick4dr]

This thread is making me salivate, Ive never wanted to hand over money for a part so fast! Tune date for Oct 17th @ EFI, Maybe, just maybe get it by then, pretty pretty please!?!

[GrimmSpeed]

So - pressure and amount of air are at play, and that part was clear in my mind, but I wasn't thinking through how the front end efficiency for the turbo could benefit making the turbo work less to get the same result. Makes sense to me. Sorry to keep you away from your duties... I just like to science.

 

Thanks, Chase!

 

Hey no problem, I also like to science. Plus we're proud of our work, and we like to put in the time to help people understand our parts. The more you know and understand, the easier it is to make a decision if you really want/need things like an intake.

 

Sure. Roll out with the GB. Show me yours and I'll show you mine.

 

But seriously, love the ongoing support and camaraderie. These types of relationships are why our 6-10 year-old cars still have such a devout enthusiast following. Good stuff, forreal.

 

Plus they're just really, really cool cars. Damn good looking too if you ask me. Thanks for the support as well!

 

Chase, you've credited me with several statements or questions made by others. Could you correct that please?

 

Yeah, I'll get right on that!

 

Anywhere we can just put our names to be notified when the group buy starts or an expected date? I don't want to miss it but I also don't want to have to check here every day

 

Yeah we usually will have a newsletter for specific products that you sign up for, and it gives you updates and helps you not miss the groupbuy. I'll talk to Matt about that. Or even easier, maybe we can just set a date for when the GB will start, i'll see what we can do!

 

My man Art from GS is at it again! Lets get us some Exterior Aesthetics in the works! We need Over Fenders ASAP!

 

 

Your Braddah from the 808~Kai

 

Bahahaha and what exactly is Art at? I dunno if you noticed or not, but GrimmSpeed doesn't make too many body parts

 

I don't understand any of this I just like GrimmSpeed parts. Sub'd!

 

Well that's not a terrible thing, thanks for the support we appreciate it!

 

What are the chances of getting an intake for the 5th gen, something like a snowball in hell? I could really use a nice intake for this build.

 

Yeah, probably about that. It really looks like the 2015+ WRX intake we make would fit, but obviously I'm not 100% sure. I believe the legacy lacks the two upper studs for the airbox, but with the amount of custom fab on that build, I bet it wouldn't be an issue to make anything on it fit. Snorkel looks slightly different, but I doubt it's an issue. I'm assuming the MAF sensor is the newer cartridge style? I'd be excited if it did fit, that build does look outstanding.

 

This thread is making me salivate, Ive never wanted to hand over money for a part so fast! Tune date for Oct 17th @ EFI, Maybe, just maybe get it by then, pretty pretty please!?!

 

I think that seems reasonable, here's hoping at least. We've just started shipping our 2015+ WRX intakes, and I believe our attention can now be focused on this release.

 

Chase

Engineering

[fahr_side]

 

Yeah, I'll get right on that!

 

 

Thanks, seems sorted now. It might be Tapatalk that assumes all quotes in a multi-quote post are from the first author.

 

 

Yeah, probably about that. It really looks like the 2015+ WRX intake we make would fit, but obviously I'm not 100% sure. I believe the legacy lacks the two upper studs for the airbox, but with the amount of custom fab on that build, I bet it wouldn't be an issue to make anything on it fit. Snorkel looks slightly different, but I doubt it's an issue. I'm assuming the MAF sensor is the newer cartridge style? I'd be excited if it did fit, that build does look outstanding.

 

 

 

You would earn the undying admiration of the 5th gen crowd for sure. A couple told me they'd have your baby if you made them an intake... and if you do make one I would be happy to provide a good scaling to beyond 300g/s for everyone.

 

 

 

I'd have to look for bracket and the two studs. It has a really similar mounting setup to the GRB / SH9 body with the one stud on it to mount the front cover, and one bolt straight down onto the frame rail at the bottom of the rear part. The sensor itself is identical to the 4th gen LGT / GRB item, so your '15 WRX intake would of course not work without hacking it up.

 

 

 

The one thing our fab guys hate doing actually is sheet-metal. They don't have a brake press etc. Anyway, sorry for the threadjack...

[derp]

Sounds like GrimmSpeed needs to take up some 5g shiz

[gonzoman10]

So would this fit a 2008 Subaru Legacy 2.5i Special Edition 2.5L SOHC EJ253? And would we see a performance increase worth the price?

 

Sent from my LGLS990 using Tapatalk

[wicknetzel]

So would this fit a 2008 Subaru Legacy 2.5i Special Edition 2.5L SOHC EJ253? And would we see a performance increase worth the price?

 

Sent from my LGLS990 using Tapatalk

 

Won't even come close to a fit because it's a totally different engine. Even if it did, it's really hard to find appropriate tuning for the NA engine/not super worth dumping money into performance on them because gains are generally minimal.

[gonzoman10]

Won't even come close to a fit because it's a totally different engine. Even if it did, it's really hard to find appropriate tuning for the NA engine/not super worth dumping money into performance on them because gains are generally minimal.

Thanks. I got the car last week. I just want to get a little more performance out of it. New to the Subaru family and all. Still learning everything

 

Sent from my LGLS990 using Tapatalk

[wicknetzel]

Thanks. I got the car last week. I just want to get a little more performance out of it. New to the Subaru family and all. Still learning everything

 

Sent from my LGLS990 using Tapatalk

 

No worries... this forum is a great place to learn. Just make sure you do your research before you ask questions because people don't generally like to answer them lots of times.

 

I had a 2.5i before my LGT and what you will pretty much learn is that anything you want to do to a 2.5i will get you very little gain for a very high cost since the market for modding them is so small. You're better off saving your pennies to get an LGT eventually.

[Shogun506]

So from reading on here it seems like the primary benefit of this intake over something like the K&N is the increased diameter of the intake hose and the placement of the MAF not being in a turbulent area. What would be the benefit of this intake over, for example, a K&N style cone filter mounted on the end of a larger diameter intake hose that goes into a well sealed fender?

[GrimmSpeed]

Thanks, seems sorted now. It might be Tapatalk that assumes all quotes in a multi-quote post are from the first author.

 

Oh, I thought you were joking! I didn't change a thing, but at least that explains why I didn't quite get the joke...

 

You would earn the undying admiration of the 5th gen crowd for sure. A couple told me they'd have your baby if you made them an intake... and if you do make one I would be happy to provide a good scaling to beyond 300g/s for everyone.

 

Oh man, I'm like 100% positive I don't need any miniature versions of myself running around. I've worked SO hard to keep it that way too I honestly am not sure that we can make this dream possible just because it is such a small market and appears that it would require substantial changes to make it happen. But then again, I never know what the future will bring!

 

I'd have to look for bracket and the two studs. It has a really similar mounting setup to the GRB / SH9 body with the one stud on it to mount the front cover, and one bolt straight down onto the frame rail at the bottom of the rear part. The sensor itself is identical to the 4th gen LGT / GRB item, so your '15 WRX intake would of course not work without hacking it up.

 

I don't think they exist unfortunately. The LGT and GR both have the two studs, and are used as the top mounting hole for our heatshield (and on the OEM they bolt to the bracket that bolts to the rubber isolator which bolts directly to the airbox). On the 5th Gen LGT it looks like that rubber isolator bolts directly to the chassis instead, just as you've confirmed.

 

And that's so odd too about the MAF sensor being the old style. It's just like the intake difference between this intake, and the GR intake. Everything else identical, but older style MAF sensor. Really makes you think about which cars they do development for, or just what the order of development in general is. So just based on suspicion alone, it seems like the airbox would need an upper mount relocation, a different MAF hole and MAF flange, and the addition of an air straightener in order to fit our 15 WRX design into a 5th gen. It's all good info to have, and a good place to start if we ever do have the time to pick up the project.

 

The one thing our fab guys hate doing actually is sheet-metal. They don't have a brake press etc. Anyway, sorry for the threadjack...

 

That's a damn shame, I do love me some sheet metal. No problem answering the question, maybe it's something we can continue eventually.

 

So would this fit a 2008 Subaru Legacy 2.5i Special Edition 2.5L SOHC EJ253? And would we see a performance increase worth the price?

 

Won't even come close to a fit because it's a totally different engine. Even if it did, it's really hard to find appropriate tuning for the NA engine/not super worth dumping money into performance on them because gains are generally minimal.

 

Thanks. I got the car last week. I just want to get a little more performance out of it. New to the Subaru family and all. Still learning everything

 

No worries... this forum is a great place to learn. Just make sure you do your research before you ask questions because people don't generally like to answer them lots of times.

 

I had a 2.5i before my LGT and what you will pretty much learn is that anything you want to do to a 2.5i will get you very little gain for a very high cost since the market for modding them is so small. You're better off saving your pennies to get an LGT eventually.

 

Thanks Wicknetzel for answering that for me, I've been swamped with fab work the last few days. And Gonzoman10, welcome to the Subaru family! Honestly though, unless it's the BRZ, I know next to nothing about naturally aspirated Subaru performance potential, but I know that info is on this forum, just in another section

 

So from reading on here it seems like the primary benefit of this intake over something like the K&N is the increased diameter of the intake hose and the placement of the MAF not being in a turbulent area. What would be the benefit of this intake over, for example, a K&N style cone filter mounted on the end of a larger diameter intake hose that goes into a well sealed fender?

 

So, I read, and re-read this question a few times, as I was a little confused. But I think I can break it down:

 

"What would be the benefit of this intake over, for example, a K&N style cone filter mounted on the end of a larger diameter intake hose that goes into a well sealed fender?"

 

Well, probably the biggest benefit is that our intake covers all these points that you're asking for about. Our intake IS the larger diameter. Our intake does go into a well sealed fender. Both things the previously mentioned intake does not do/have.

 

However, I think the most important aspect of this intake is the OEM-like MAF readings (MAF curve). Being easy and predictable to tune (as a MAF scale is REQUIRED) is a massive benefit as less time tuning is less money spent, and more time driving, but also because you won't end up with wonky fueling, hesitations, and any general problems that you don't usually see with stock intake. This sounds easier to achieve than it actually is, and is a product of lots of time spent with CFD and real world testing. Where air enters the filter, filter venturi, air straightener design and presence, MAF sensor placement (how far from entrance, what clocking, and at what depth), MAF distance from nearest bend ALL play a part in obtaining the MAF curve we have. And that's still saying nothing of the fact that this intake isolates the MAF sensor inside the heatshield to further improve sensor accuracy.

 

Plus I think it just looks a hell of a lot better and more stealthy. I don't necessarily even want to see a cone filter when I open up my hood. To some a cone filter screams "performance," and to others it screams "distasteful," for lack of a more appropriate word. The isolated filter design also greatly helps how the intake is perceived to the driver. The sound is there when you want it, and not when you don't. So you're not just hearing constant wooshing while cruising, which will get old fast to many.

 

I can go on and on and on, but I believe this info is already in the thread if you go back and take another closer look at the posts I've written.

 

Thanks!

Chase

Engineering

[LegacyDan]

Now that much I do not know, as I've never touched a JDM LGT here. I think that if I saw some pictures of the intake area with the intake and airbox removed I'd be able to tell, but that's really the best I can do without using my own two eyes in person.

 

I don't mind being a test bed to help with fitment confirmation for RHD models

[GrimmSpeed]

I don't mind being a test bed to help with fitment confirmation for RHD models

 

Excellent, I look forward to it!

 

A lot of people have asked for a better way of knowing when the groupbuy starts, so we've made a newsletter that will email you an update when we're ready to roll out the group buy:

 

Click here to signup for the GrimmSpeed LGT Intake Updates Newsletter!

 

So sign up, and you don't have to worry about missing out!

 

Chase

Engineering

[magnusonsubie]

I noticed the bit about color preference. Any chance we could opt for something other then red or black? Like Blue?

[derp]

I noticed the bit about color preference. Any chance we could opt for something other then red or black? Like Blue?

 

You stop it with that ricer talk.

[magnusonsubie]

You stop it with that ricer talk.

 

But I've got blue accents on my black wagon already to match the blue flake in the OBP If blue isn't available I'll just get black

[alex0856]

I was forced to do blue accents under my hood because blue was all VenAir had left from the group buy. So now I've got blue hoses all around, blue LWCP, and would just LOVE a blue CAI to go with it...

[magnusonsubie]

I was forced to do blue accents under my hood because blue was all VenAir had left from the group buy. So now I've got blue hoses all around, blue LWCP, and would just LOVE a blue CAI to go with it...

 

I still need to get that hose kit. I'm just lazy and my hoses are all fine. Someday though

[alex0856]

I'm doing it as PM with my rebuild. Since I don't have to install them it made it 10 times as more tempting.

 

Because really, who wants to replace the BOV hose themselves?

[derp]

But I've got blue accents on my black wagon already to match the blue flake in the OBP If blue isn't available I'll just get black

 

black is the only acceptable option.

 

my engine bay is like jay-z, all black everything. rad shroud, hoses, intercooler, alt cover, and gonna be intake

[Streetlegal]

Hmmm I wonder if this would fit with my FMS FMIC. Seeing a few of the intake pictures around with it it looks like it might. Such a pretty intake and I want it

 

Thoughts Chase?

 

http://i167.photobucket.com/albums/u160/awalla5150/FMSfmic2.jpg

http://i167.photobucket.com/albums/u160/awalla5150/fmsfmic3.jpg

[covertrussian]

Well, probably the biggest benefit is that our intake covers all these points that you're asking for about. Our intake IS the larger diameter. Our intake does go into a well sealed fender.

 

Speaking of sealed fender well's... I've been testing different intake setups: CAI, WAI, Milk Jug/Resonator delete, and I'm beginning to question how good ("cold") the fender well actually is.

 

A non sealed cold air intake would still reach pretty high IAT's from idling, but at highway speeds I was hitting 0-2*F above ambient which is excellent. After testing CAI's I wanted to see if removing the milk jug/resonator would help. This setup would be more sealed then a CAI since the stock airbox mostly blocks off the fender well from engine bay. To my surprise the IAT's would still creep up very quickly, just as bad as with the CAI. Reinstalling the milk jug made the IAT's creep up much slower, this is odd because stock intake gets it's cold air from under the hood still.

 

I think I found what's causing fender well not to be "cold" is the exhaust manifold and Up pipe being right there and the belly pan not fully sealing against the body, which leaves a ~2" wide and ~4" long spot that heat can leak into the fender well through. This is probably fixable by making a heat shield and extending the belly pan more.

 

Have you guys seen similar results on the WRX, if not it might be more sealed off then Legacy's are?

 

Also the front facing snorkel seems to do a fantastic job even though it's still in the engine bay, did you guys test with cutting a window in the your airbox and attaching the stock plastic snorkel to it? Two sources of fresh cold air seems better then one (especially since fenderwell tends to be not so fresh and cold).

[GrimmSpeed]

I noticed the bit about color preference. Any chance we could opt for something other then red or black? Like Blue?

 

Blue powdercoat is something we've looked at for years. Occasionally we get a request for it and we looked into it years ago. Unfortunately we have never found a blue powdercoat in either wrinkle or texture that we like, or that matched our expectations. Years back one of our employees spent a good amount of time trying to find one that was a good match for WRB (which would be awesome), but there just isn't one that we know of in wrinkle or texture. "Well, why don't you just do it in a gloss coating then?" is probably what you're thinking. Well, we think it looks cheap, like you've just spray painted a part. Also if you do manage to scratch or ding it, the textured/wrinkled coating do a substantially better job of hiding it. And often during design I will push the limits of what a mandrel bender can hold as far as clamping and distance between bends goes, so lots of time our raw pipes will end up with clamping marks from this operation. The wrinkle and texture coatings do a good job of hiding these, which end up being unsightly with a gloss coating.

 

So that is the long answer why we don't offer blue currently until we find one that we do like. But honestly with it being so long demand, it's not on our radar right now.

 

Hmmm I wonder if this would fit with my FMS FMIC. Seeing a few of the intake pictures around with it it looks like it might. Such a pretty intake and I want it

 

Thoughts Chase?

 

Well, I googled pictures of the FMS (and the other ebay intercoolers under different names, CNT, CX, etc) until I could find a good picture that shows me where the pipe enters the section where our airbox sits. It looks like the intake pipe and filter have a chance of fitting, but not so much the airbox. The airbox will need to be hacked up quite a bit to fit the intercooler pipe going through that area. And it's not acceptable to run this intake without the airbox, as the airbox supports it, so it MIGHT work with some extensive modification. That is about as concrete of an answer that I can give ya.

 

Speaking of sealed fender well's... I've been testing different intake setups: CAI, WAI, Milk Jug/Resonator delete, and I'm beginning to question how good ("cold") the fender well actually is.

 

A non sealed cold air intake would still reach pretty high IAT's from idling, but at highway speeds I was hitting 0-2*F above ambient which is excellent. After testing CAI's I wanted to see if removing the milk jug/resonator would help. This setup would be more sealed then a CAI since the stock airbox mostly blocks off the fender well from engine bay. To my surprise the IAT's would still creep up very quickly, just as bad as with the CAI. Reinstalling the milk jug made the IAT's creep up much slower, this is odd because stock intake gets it's cold air from under the hood still.

 

I think I found what's causing fender well not to be "cold" is the exhaust manifold and Up pipe being right there and the belly pan not fully sealing against the body, which leaves a ~2" wide and ~4" long spot that heat can leak into the fender well through. This is probably fixable by making a heat shield and extending the belly pan more.

 

Have you guys seen similar results on the WRX, if not it might be more sealed off then Legacy's are?

 

Also the front facing snorkel seems to do a fantastic job even though it's still in the engine bay, did you guys test with cutting a window in the your airbox and attaching the stock plastic snorkel to it? Two sources of fresh cold air seems better then one (especially since fenderwell tends to be not so fresh and cold).

 

The legacy and the WRX are extremely similar as far as the engine bay goes, and during testing and cruising it was typical to see a value of about 8-10 decrees above ambient temperature while cruising. A value of 0-2 above ambient (especially 0) seems ambitious as the act of flowing through an air filter (restriction) will raise the temperature of the air some. This is why I always wonder what temperature people are referring to as "ambient" when they report that particular value. An external thermocouple, or the value reported on your dash?

 

However, as far as the air being being "not so fresh and cold:" It sounds like you're basing that on the fact that the AITs still creep up faster when you're idling? You'd be right, as the major player in that equation is still stagnant air. However the fact that when you start moving again you still achieve whatever value above ambient that you did with the different set up is indicative that the inlet air area acts just fine.

 

I think it's important to look at the intake as a system for this. Yes, isolating the air inlet from the engine bay is important, and is pretty easy to do. 8-10 degrees over ambient is pretty darn good, and the difference in power output between 0 degrees and 10 degrees is in theory about 1hp.

 

So say we DO try and incorporate the snorkel to get that theoretical 1hp back. Well, unfortunately you can't just cut a hole in the airbox and fit the snorkel. The snorkel would try to occupy the same space that the filter does. So in order to fit the filter now we have to change the pipe design. We've got two choices for routing now:

 

1. We go behind the snorkel. It takes two bends to get there now, and we're forced to greatly reduce the straight length of tube after the MAF, which has an influence on flow before the MAF. Also, now we have a fresh air dump localized in front of the filter. This works fine for fresh air, but works horrible for air distribution. Now you have a mean amount of air entering the filter sideways, and making a sharp turn towards the venturi/straightener/MAF. Again, it works because the vacuum in the inlet pulls from all around the filter, but as I said there is a heavy influence from the momentum of the snorkel flow. You'll even be able to see the evidence of this because a small area of the front of the filter will be visibly loaded with dirt, debris, leaves, bugs, etc. But if we do this we can block off the air entering from the fender well, and ONLY allow air from the snorkel (assuming a sealed airbox with a bottom). Unfortunately, we've ruined the OEM-like MAF curve that we worked so hard to achieve by changing literally everything about the intake in order to feed it from only the snorkel. And we've also added elements into the design to increase restriction by adding an extra bend, and greater overall bend angles.

 

Also, someone else already makes that intake

 

2. We put the filter below the snorkel. Now we have to not only make the pipe longer, add an extra bend, increase the bend angles, place the filter lower and closer to the ground, and overall increase restriction. But most of all, this design no longer allows for using snorkel-only air without an overly complex and expensive airbox, and we end up with the same conundrum as we started out with. Overall, I'm not even 100% sure that this design is possible as far as clearing the powersteering lines, the snorkel, and entering the fender well. There is a minimum centerline radius and distance between bends that can be achieved with any diameter pipe, and to exceed that either requires extremely expensive bend dies and clamps, or cutting and welding. Both of which are more expensive, and will lead to a more expensive part.

 

All in all, any system will have advantages and compromises. Whether it's cost, complexity, restriction, etc. If we have to sacrifice 1hp for a gain of 1psi (good for more than 1 hp) we'll do it. Even better if in the process we also isolated the MAF for accuracy, achieved an OEM-like MAF curve, minimized complexity, simplified installation, and kept cost down all at the same time.

 

What is overlooked too, when it comes to our dyno testing is that we put out intake at a serious disadvantage compared to the stock airbox, and still made power. In testing there was one fan blowing on the intercooler, and one fan blowing into the radiator. Pretty standard. Derp's stock airbox was not equipped with a snorkel, and the hood was up. There was MORE than enough ambient air for the stock airbox to breathe in this situation. However, the same can not be said for out intake, which was basically in the "idling" condition as without the car moving the supply of air was stagnant at best. We didn't log our pulls, but it's more than safe to assume because of this our intake was seeing higher IATs. Yet still making more power due to the decrease in resistance, and increase in efficiency. This is concrete evidence of why we will not make a sacrifice in design to chase after 10 or even 20 degrees of inlet temperature.

 

Remember, "this is chess, not checkers."

 

Chase

Engineering

[Streetlegal]

Blue powdercoat is something we've looked at for years. Occasionally we get a request for it and we looked into it years ago. Unfortunately we have never found a blue powdercoat in either wrinkle or texture that we like, or that matched our expectations. Years back one of our employees spent a good amount of time trying to find one that was a good match for WRB (which would be awesome), but there just isn't one that we know of in wrinkle or texture. "Well, why don't you just do it in a gloss coating then?" is probably what you're thinking. Well, we think it looks cheap, like you've just spray painted a part. Also if you do manage to scratch or ding it, the textured/wrinkled coating do a substantially better job of hiding it. And often during design I will push the limits of what a mandrel bender can hold as far as clamping and distance between bends goes, so lots of time our raw pipes will end up with clamping marks from this operation. The wrinkle and texture coatings do a good job of hiding these, which end up being unsightly with a gloss coating.

 

So that is the long answer why we don't offer blue currently until we find one that we do like. But honestly with it being so long demand, it's not on our radar right now.

 

Well, I googled pictures of the FMS (and the other ebay intercoolers under different names, CNT, CX, etc) until I could find a good picture that shows me where the pipe enters the section where our airbox sits. It looks like the intake pipe and filter have a chance of fitting, but not so much the airbox. The airbox will need to be hacked up quite a bit to fit the intercooler pipe going through that area. And it's not acceptable to run this intake without the airbox, as the airbox supports it, so it MIGHT work with some extensive modification. That is about as concrete of an answer that I can give ya.

 

Hmm ok. I really wouldn't want to cut it up. I'll see if I can find some more pictures, or just go put the pipe on and do that.

 

As far as textured blue powdercoat goes, I have seen quite a few that look and hold up nice. Out of curiosity what are some of your expectations of it? I've had really good results with the powder from this company but I haven't tried their textured blue. Figured I would at least throw my thoughts out there

 

https://www.powderbuythepound.com/Blue-Oval-Racing-Wrinkle/

[covertrussian]

The legacy and the WRX are extremely similar as far as the engine bay goes, and during testing and cruising it was typical to see a value of about 8-10 decrees above ambient temperature while cruising. A value of 0-2 above ambient (especially 0) seems ambitious as the act of flowing through an air filter (restriction) will raise the temperature of the air some. This is why I always wonder what temperature people are referring to as "ambient" when they report that particular value. An external thermocouple, or the value reported on your dash?

 

I'm using the dash temperature gauge, from what I remember seeing it's mounted infront of the car, right behind the bumper. Which means it should get a fairly accurate ambient air as you drive. I find it to be more accurate then using things like weather.com (which is usually 2-3*F off my house and car temps).

 

I typically see 5-15*F over ambient in the city, usually 4-5*F over ambient highway, but not less then 4*F unless it's freezing outside. With the CAI I saw temps jump higher in the city but much lower on the highway, I didn't really test the resonator less intake much in different driving conditions (only dyno logs).

 

However, as far as the air being being "not so fresh and cold:" It sounds like you're basing that on the fact that the AITs still creep up faster when you're idling? You'd be right, as the major player in that equation is still stagnant air. However the fact that when you start moving again you still achieve whatever value above ambient that you did with the different set up is indicative that the inlet air area acts just fine.

 

I think it's important to look at the intake as a system for this. Yes, isolating the air inlet from the engine bay is important, and is pretty easy to do. 8-10 degrees over ambient is pretty darn good, and the difference in power output between 0 degrees and 10 degrees is in theory about 1hp.

 

There are actually two issues, how fast it rises and how high it rises in the same amount of time. I found that with the removal of milk jug, the temps rose quicker and higher then on a 100% stock setup. This means that the fender well is polluted with hot air, more so then the stock snorkel. I'm impressed with how well the stock snorkel can keep the IAT's down even though the snorkel has no direct outside outlets (the hood covers it), A+ to Subaru Engineers for great design.

 

You are correct 10*F gains/losses you minimum power and it's all moot once you start moving and I didn't think it was a big deal until I started mocking with intakes myself. I found that I was detonating a lot easier since my incoming air was much hotter, this resulted in having to retard more timing in the IAT Compensation table. The problem with this now was I was pulling 5-10* of timing now just to avoid detonation in the medium powerbands, which also means I was running that much less timing up top too resulting in major power loss.

 

My testing showed that I gained over 20whp on my custom intake if my IAT's stayed close to ambient (in my tests ambient was around 85*F) before doing the street dyno logs, but if I did a log right after being stopped for a little bit my power gains were same if not less then with stock intake. This is hard to emulate on a chassis dyno because the hood stays open and you have constant fans on (for engine safety reasons).

 

So say we DO try and incorporate the snorkel to get that theoretical 1hp back. Well, unfortunately you can't just cut a hole in the airbox and fit the snorkel. The snorkel would try to occupy the same space that the filter does. So in order to fit the filter now we have to change the pipe design. We've got two choices for routing now:

 

1. We go behind the snorkel. It takes two bends to get there now, and we're forced to greatly reduce the straight length of tube after the MAF, which has an influence on flow before the MAF. Also, now we have a fresh air dump localized in front of the filter. This works fine for fresh air, but works horrible for air distribution. Now you have a mean amount of air entering the filter sideways, and making a sharp turn towards the venturi/straightener/MAF. Again, it works because the vacuum in the inlet pulls from all around the filter, but as I said there is a heavy influence from the momentum of the snorkel flow. You'll even be able to see the evidence of this because a small area of the front of the filter will be visibly loaded with dirt, debris, leaves, bugs, etc. But if we do this we can block off the air entering from the fender well, and ONLY allow air from the snorkel (assuming a sealed airbox with a bottom). Unfortunately, we've ruined the OEM-like MAF curve that we worked so hard to achieve by changing literally everything about the intake in order to feed it from only the snorkel. And we've also added elements into the design to increase restriction by adding an extra bend, and greater overall bend angles.

 

Also, someone else already makes that intake

 

I forgot that you have to put your intake in front of the stock location, which does mean that snorkel will be digging into the filter it self unless you move it back with bends or make a new snorkel. I also wonder if there is an issue with pressure differentials with having two entry points (this is why it's important to have the belly pan on these cars.)

 

About someone making the intake already, While this is true, the stock setup is riddled with bends, flexi-ripples in the piping, and sharp 90* turn right before the MAF (all bad for power). Getting a "straight through" intake like most aftermarket ones are with same cooling capabilities as stock intake is the goal here.

 

 

All in all, any system will have advantages and compromises. Whether it's cost, complexity, restriction, etc. If we have to sacrifice 1hp for a gain of 1psi (good for more than 1 hp) we'll do it. Even better if in the process we also isolated the MAF for accuracy, achieved an OEM-like MAF curve, minimized complexity, simplified installation, and kept cost down all at the same time.

 

What is overlooked too, when it comes to our dyno testing is that we put out intake at a serious disadvantage compared to the stock airbox, and still made power. In testing there was one fan blowing on the intercooler, and one fan blowing into the radiator. Pretty standard. Derp's stock airbox was not equipped with a snorkel, and the hood was up. There was MORE than enough ambient air for the stock airbox to breathe in this situation. However, the same can not be said for out intake, which was basically in the "idling" condition as without the car moving the supply of air was stagnant at best. We didn't log our pulls, but it's more than safe to assume because of this our intake was seeing higher IATs. Yet still making more power due to the decrease in resistance, and increase in efficiency. This is concrete evidence of why we will not make a sacrifice in design to chase after 10 or even 20 degrees of inlet temperature.

 

This is exactly why I'm not sold on stock airbox designs for aiflow, they are decent for factory setups but not the most efficient for power. But stock intake is very good at being an inefficiently flowing cold air intake!

 

This also explains why you guys didn't gain as much power compared to the WRX, I wish you guys logged the IAT's and finial ignition timing, that tells 90% of the story .

 

Remember, "this is chess, not checkers."

 

Chase

Engineering

 

It really is all about compromise, loose a pawn to save the queen.

[GrimmSpeed]

Hmm ok. I really wouldn't want to cut it up. I'll see if I can find some more pictures, or just go put the pipe on and do that.

 

As far as textured blue powdercoat goes, I have seen quite a few that look and hold up nice. Out of curiosity what are some of your expectations of it? I've had really good results with the powder from this company but I haven't tried their textured blue. Figured I would at least throw my thoughts out there

 

https://www.powderbuythepound.com/Blue-Oval-Racing-Wrinkle/

 

I would honestly cut up the airbox if you go that route, because you've already bought it, so cutting it up and trying is still better than just throwing it away. I have to to reiterate that it's important to support the intake, which without the box you'd need to fab something up.

 

And that's still assuming that even with the box cut perfect that the intake fits, which I can't confirm, but have a suspicion it will.

 

And I too have spent some time on that site for my own personal reasons. however, that shade of blue for example, is too light, and looks like "Old Ford Blue," and not the "World Rally Blue" that we had our heart set on.

 

This is exactly why I'm not sold on stock airbox designs for aiflow, they are decent for factory setups but not the most efficient for power. But stock intake is very good at being an inefficiently flowing cold air intake!

 

Well, the stock intake is a different kind of compromise, and it does a damn good job of doing what it needs to. It needs to be cheap, use a cheap and readily available filter, it needs to be quiet, and it needs to be able to be produced quickly, etc. It also has to be modular. If you think about it, there are like 3 or 4 different airboxes across most subarus (turbo and non-turbo) with only minor changes to each to accommodate different cars. And these changes can be made by swapping out pieces of the mould. This is hundreds of thousands of intakes!

 

So it does a great job of what it needs to do, when looked at as a system. But you're exactly right.

 

This also explains why you guys didn't gain as much power compared to the WRX, I wish you guys logged the IAT's and finial ignition timing, that tells 90% of the story .

 

Well that's a little different too. Because we didn't have a stock tune for that car, our baseline was someone else's road tune. Who knows if it made more or less power than what it would have with a stock tune. But the main point to take away from that dyno day is that after the stock intake was protuned (which was a decent gain) we didn't do any further tuning after we swapped to our intake other than the MAF scale. More boost and more timing would have made another 15-25hp easily according to our tuner, but he and derp refused to on a car that sees occasional sustained track time on an aging motor. When the tuner heard he had put on over 200 track miles in a weekend just a few weeks earlier he made sure to keep things WAY conservative.

 

It really is all about compromise, loose a pawn to save the queen.

 

I like you.

 

Chase

Engineering