HKS Intake Duct V2: yes or no?
 

I searched around a lot, but I didn't fint an answer: is this part effective for performance in a NA car or not?

im sure someone, somewhere made 3 more horsepower with one, but thats not really the value of in intake in my mind. theyre cool engine dressup, you get to display a great brand like HKS, and have fun turning wrenches.

I have the Greddy one that picks up air from the bumper opening. It keeps intake temps surprisingly low when the car is moving.

I’d like to know too. One would think it would be worse than oem because it deletes all of those factory airflow resonators that keep the flow rate as high as possible. But some people have reported an increase in throttle response with units like the HKS, and even OFT has recommended the snorkel mod where you heat up a pre-cut OEM duct and stick the bottom 2 liter coke bottle into the opening so the opening becomes more like a circle.

Just so damn expensive for the Japanese name brands!

Makes me wonder why somebody with a 3D printer hasn’t just made their own design to sell for a fraction of the cost lol

https://www.ft86club.com/forums/showthread.php?t=140888

I've seen that one. That one is a pretty blatant rip off of the HKS product, as the OP even said haha.

I meant more along the lines of somebody producing their own version of it. Maybe using the HKS as the base, and then making mild design changes.

Would be really cool if somebody made something more similar to the GReddy one.

The problem with all those designs and factory “cai” is you have no airflow coming in from front bumper it’s just pulling whatever random stagnant air in that area. Front crash bar and foam block all air from that side so have small holes on the back of the plastic piece behind intake.

Beatrush bumper bar completely opens up all that airflow to be able to actually pickup moving cold air from the front end.

There are several air scoops available that solve this. Greddy pictured, AutoFactory, LegSport.. I can't say that it added any power even on the butt dyno. But the IAT we lower so thats nice.

https://i.imgur.com/vubkYFg.jpg

That is done on purpose I believe. I may be wrong on this, but I think the intake does better drawing from a low pressure area (behind the bumper cover) than from a high pressure area (vent exposed to the front of the car).

I think even BMW switched it up from a ram air style intake to drawing from behind the bumper like our cars do.

https://www.rawautos.com/wp-content/...3GTS-M3CSL.jpg

Velocity through the filter is pretty low. Only way in increase that is with a pressure difference. Airflow has a dynamic pressure in addition to a static pressure. When you slow that airflow down (with the radiator) you transfer that dynamic pressure into greater static pressure, which in the twins is captured in the grill opening. That static pressure is reduced less by changes in flow direction than dynamic pressure, and also suffers from less turbulence. As such, using the static pressure from the grill opening is theoretically more efficient in producing clean, high pressure airflow than a direct duct to the front of the car.

OK, this is all true if talking of ram air intakes, but HKS duct is not affected by speed velocity, as it stays behind the bumper. So, no CAI, loss of resonators, shorter and larger, air temperature is colder?

Oh! This just replaces the factory "snorkel" with a shorter piece and larger opening? I imagine it will change the sound but not have much more effect if you keep the intake baffle underneath it.

Do you think with something like this you could see a bit more effect?

https://dpbfm6h358sh7.cloudfront.net...1031667346.jpg

It’s probably done because of design limitations without drastically changing the bumper brace or removing the bumper foam piece and spending more money. The oem design has no airflow access from the front, it is just taking in stagnant air adjacent to the engine bay only blocked from the engine by a thin piece of plastic and a little foam. Seems far from ideal.

I am not talking about changing to a ram system with high pressure air either. Just having access to the fresh cold air coming through the front grille and being able to have that air cool the air in the space previously occupied by bumper bar and foam. And possibly being able to “suck” air from that cold stream but not “ramming it” and not redirecting the high pressure air to come in the grille and then curve up to the filter location or bringing the intake duct end closer to the high pressure air either. Just allowing a direct link between filter and direct cold air while maintaining a low pressure zone.

My IAT dropped a good amount switching to my custom setup. Although my reasons for switching and doing this had nothing to do with this was just a pleasant bonus. Wish i had pics when bumper was off.

Not really. Better than cutting a hole through the bumper, but I wouldn't expect much better performance. Maybe you get a bit more dynamic pressure converted that isn't flowing through the radiator, but you lose some of that to bleeding off the edge and you get more turbulence in the inlet. I honestly haven't actually done a real analysis on this car, but having some experience in airflow (I'm an aeronautical engineer by education), it seems like the inlet was pretty well optimized for the current solution. This MIGHT change if you were to reduce pressure in the engine bay by way of vents and the like. Then you might benefit from a more direct intake snorkel.

One note is that (iirc) Perrin's r&d paper on their CAI said they experimented with removing the air dam between the grille and filter element and found that it created some turbulence that affected the MAF. Since accurate MAF is kind of important for making power, they left the air dam alone.

I couldn’t find any information or testing in regards to the front crash foam.

Besides not being a fan of oiled filters, I also didn’t like how the perrin filter “sat”. In Perrin’s picture it is fully exposed on all sides but on many other peoples pictures and including mine it always sat on the crash bar and was basically blocked by the bottom and “lip” sticking up so only airflow could go in from behind and up to the top basically limiting service area. Switching to beatrush crash bar and swapping on a 2.75” x 11” coned dry filter it is now truly open all around.

I also don’t see how it would create turbulent air removing the foam. Air comes in straight at / into radiator at which point it will diverge into radiator and some will go up and into the holes on the plastic piece. I don’t see what would really cause it to instantly diverge up prior to encountering any resistance or obstacle. The space directly behind the front bumper which is now wide open and has a straight line to the filter should still be a low pressure non turbulent zone just much closer or straighter path to fresh cool air.

Not saying it’ll make gains, but possibly maintain HP / less heatsoak type issues.

Disclaimer: I also have a sprintex SC may change some factors regarding all of this and the benefits etc...

Honestly, the Perrin could be the absolute best intake on the market and I still wouldn’t be interested just because it requires removing the whole bumper to service lol

That’s a downside true. At least it only takes about 30mins to remove/install once you know how.

Also a chance this new skinnier longer filter may be able to slide in with only undoing the top bolts/clips.

Yeah the removal itself is easy. It’s more an issue with all the clips and tabs getting worn down and inevitably breaking and/or loosening after a few times.

On a slightly related note, I had a Grimmspeed intake on my 13 FRS and had no issues. The data logging showed everything checked out well with regards to the MAF scaling after install. Had a slightly louder and more pleasant induction note.

No real noticed change in power. MAYBE pulled a slight touch more in the very top end before dying off, but after a couple pulls, I couldn’t really tell a difference.

I honestly just hate looking at the OEM unit in the engine bay. Between the piping, the snorkel, and the sound tube, it’s all just a giant eyesore to me.

I wonder of the 2013-2016 intake tubes work for the 17+. The HKS Carbon one is nice. Pricey and useless, but I almost don’t even care Hahahaha

7 removals

Lucky you. The corner lights alone have proven to give tons of people issues after removing and re installing the bumper a few times.

Air pressure diverts the flow before those particular particles hit the radiator. Gas particles bounce off each other as well as solid or liquid surfaces. The radiator slows down the flow, essentially causing a traffic jam. The resulting bow wave causes the entire front opening of the car to increase in static pressure while losing dynamic pressure (due to loss of velocity). The plastic air dam above the radiator has vents which allow static pressure to equalize across it, but damps fluctuations in dynamic pressure (turbulence). This turbulence comes from changes in speed, random pockets of hot/cold air, etc. Basically the general noise of a pickup 12" off the ground in possibly windy conditions. Apparently that turbulence was enough to give the Perrin folks pause, considering their goals at the time.

Anyway, the rate of airflow near the intake pickup is quite low, so the directness of flow actually has very little effect. The vents in the air dam probably allow plenty of flow for the engine in any NA application. FI, you might start seeing that as a restriction.

The benefit of a Perrin-like setup is that the air spends less time inside the hot engine bay, and the filter absorbs less heat. Plus, aluminum is a pretty good insulator from heat.

Finesse
Lol, after 6x it was slightly worse than the picture shows. Still not really bad or anywhere near some pics I’ve seen of other bumpers. But while doing the 7th removal i replaced the headlight bracket and side bracket and put 3 of the tab supports on each side. Got it back to near factory. And just swapped the filter, so I’m done removing bumper for a long while.

does greddy fit 2020 brz?

Thats the one you need to cut the foam crash bar in order to install? If so, was it an easy install?

Other than taking the bumper off, it was very straight forward. I did not cut the foam I just removed it.

The Skunk2 CAI actually has something similar built-in, and since its all one piece, its more of the "air tight" type setup that all the others talk about when mating mix/match pieces, or even the OEM stuff and its foam type seals.. I have the skunk2 CAI, but havent installed it yet.

Hate to say it, but just do a drop in filter and be done. If you want to get rid of the sound stuff like me, just get a Perrin inlet tube or equivalent. In 4 years of owning the car, every year I think about getting the GS intake or another intake, and I do some searches and then it’s never really worth it other than for looks. I have headers and a tune. Not spending 300 bucks for looks, although I have come close a few times. Probably do it again next year, but then read my post and not do it.

I just paid 233.00 for the Skunk2 (havent installed it yet) considering the price of a K&N drop in at an avg of $50, I really paid 180.00 for the skunk2. I really think it differs for every car. For example, line up 10 BRZs and install the same intake on all and I bet we'd all be shocked at the variations in results. I still think they're probably worth it if you can get a custom tune..

A custom tune with a drop in and a tune with the Skunk2, dyno both after waiting for the car to learn the new settings. I am 100% sure there will be so so little difference between the two that it'd fall into the +/- area of a dyno.

Try and justify it all you want but there is a reason why a lot of people say to save the money and just get a drop in filter.

Also you CANT compare one car to another, that's not how that works.
The cars are going to vary wildly period.

It’s only money. It won’t hurt.

Meh intakes are a waste. Remove the sound generator tube and get a drop in filter and call it a day...

Sent from my GM1915 using Tapatalk

Got a good deal on the V1. Did it for the swag points and to hear some nice whooshing noises. Not sure I would pay full price though


Even pros seem to like it, even if it admittedly doesn't really add all that much.
--There is a tune and dyno comparison at the end, though apparently the car already has a header so it doesn't really say much about the intake duct itself
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https://www.youtube.com/watch?v=eJQkpVJ8RFc
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I'm not really trying to justify anything, I'm only addressing the original question regarding the intake duct.. also if you can't line up 2 brz/frs/86 respectively and compare (one stock and one with an intake) then that would be proof saying it does nothing is irrelevant, its only relevant to the one it was tested and confirmed on..

Tons of claims on intakes both ways, yet no dynos... so yea, basically were all just speculating.. until someone produces dyno test results that is.. until then though.....

This debate was done years ago for the WRX. Plenty of data said the stock air box was good until 400 hp, but so many wanted an intake. In the twins case the intake will not hurt, but on the WRX it definitively could hurt and did for many who tried it. Spending money on a tune for an intake is wasteful and many did not do it, Most that wanted added am intake to other changes before they got a tune, which was fine. Still some tuners had trouble with the maf.

Simple thing is if you want one, get it. Just don’t expect any real gains over a drop in filter, other than looks and sound.

Nice, I was looking at that too, the place of the stock snorkel will much help on keep suck the cleaning air, but the intk temp will be higher than if it could suck directly on the frontal face.

Just ordered from Jp, I hope it will drop the intk temp and gives me more consistent power output when I'm on the track.

Awesome! My intake temps are within 10° of ambient when moving.