New owner of a 2014 IS350 as of last week! One of my absolute favorite cars period since 2006, finally own. Black on black, super excited, blah, blah, blah (no but really I've lost a lot of sleep this week )

First thing I did when thinking of mods is take a good look at the intake.
Noticed after about a minute I wasn't sure I was going to get something much better by going aftermarket. Don't care if it's shiny. And definitely not leaving the engine bay victim to outside elements and some cone filter sucking on hot air all day (really? Although I know they usually sound great) After hours of reading threads on here...I'm convinced I was right and this stock intake is good-to-go. (ok, minus that silly sound enhancement...thing).

I do have a K&N drop-in arriving tomorrow, and have one last thought on this intake before I move onto exhaust....

Has anyone increased air-flow into this stock airbox? No, I don't mean drilling holes for increased sound. And I will not remove airbox entirely, unless there's a bigger aftermarket one.
Maybe this snorkel can be enlarge or another one built in it's place?. Perhaps a sealed passage to down behind the fender/bumper to compliment the snorkel already in place?


(I did something like this on my old SC300...looked pretty garage rigged but better than anything they sold)

 

If you were to look at the FSport intake, you'd see it connects to the stock snorkel that comes from the front of the hood. Also there is a hole cutout in lower air box where it sits right behind the right side headlight. I bought the FSport filter, and just cut out a hole in the stock air box behind the headlight. I did buy an HPS intake tube too.

 

Ok so the same snorkel, but also a second cutout in the front side. That second cut out probably sounds great and hopefully far enough away it won't catch much hot air.
Does the car sound like it's breathing better? Notice increase/decrease in intake performance?

 

I don't think it's getting hot air from the engine bay because it's facing forward and it should be getting fresh air as you drive. The intake doesn't give you that much of a power gain that you can really feel. I do feel using the stock air box with the aftermarket filter is better than if you were to remove it and go with a cone filter.

 

Thanks for pointing that out. I missed seeing the F-Sport airbox had that cutout...can't be too bad I agree. And yeah I know I won't sweat too long over a potential 2 hp gain.

 

Did you end up modifying it?

 

The hole on the F Sport is just for additional growl--similar in concept to the sound generator you called "silly"

The stock intake on most premium cars tend to be optimized under hundreds of hours of testing using secret inside data crunched by supercomputers. The design is based on the exact and specific demands of the engine. Many in the blue and white world I come from tried "upgrading" their intakes with even the most expensive ones and found the stock performed best.

The intakes that do show a net gain tend to achieve that gain in the high end but sacrifice in the lower end (where you'd actually need it in real world use)

So stay stock and get an F Sport filter =) The better mod would be to remove the charcoal filter in the upper box.

 

Nope, haven't done it but I probably will. Purely to sound better as if Lexus did it...must not hurt either.

There is a thread, I believe in this forum, which someone did extensive testing on the major options for aftermarket intakes. As I believe I mentioned earlier in this thread.

​​​​​​Results were that the stock intake performs the best. Period. Regardless of what they did in the over-engineered / over-rated blue and white world ....it's for the reasons previously stated.

So the best mods are intake filter. Simply replacing the intake tube would seem to be better...but couldn't be by much (hasn't been tested really that I know).

And the point in this thread..getting more cold air into intake. Seemingly our best bet for any real performance gain out of an intake. In theory cause haven't come across anything .

 

The last thing you could do to increase air flow is replace the tube between the box and throttlebody.(I forget which vender supplies them on here but im sure Josh from Meraki Autoworks can help you out, he has everything!) the current tube is ribbed and disrupts smooth airflow.

 

Yeah that's what I meant by "intake tube".

RR Racing has a good one at a fair price. Also the F-Sport uses that design.

Besides the ribbed coupling it also has a couple other areas of loss flow it eliminates.

I should probably mention the dyno testing and what I speak of are the NA 250/350.

 

If you are going to get an aftermarket intake tube and want the best bang for your buck, then stay away from the ones that have the accordion style connectors and stick with the smooth ones. Better airflow with the smooth ones. The accordion style ones cause turbulence in the air flow. This is the reason I chose the K&N kit. Its chrome but I'm having mine powder coated gunmetal gray.

 

Yeah want a straight coupler.

I thought about the K&N one and wrapping in a header tape.
Won't look pretty but it's effective.

RR Racing one is carbon fiber and I think $100-$120

 

Funny that this discussion came up as during the past few months, I've personally datalogged a multitude of WOT pulls on my 2nd Gen IS350 using both the stock 3IS350 F-Sport Intake Pipe w/ Sound Generator and a smooth aftermarket intake pipe (in this case, the tried and true JoeZ intake pipe) and I have consistently logged higher MAF g/s #s with the JoeZ intake pipe (avg. of 2-5 g/s higher under the same intake air temperature range). Peak MAF g/s that I recorded for the JoeZ intake pipe was 254.71 g/s @ 59 degrees while the peak MAF g/s that I recorded with the 3IS F-Sport intake pipe was around 251 g/s @ 59 degrees (not shown on the below chart).



I personally wanted to use the 3IS F-Sport intake pipe as part of my engine setup specifically for the added acoustics of the sound generator but since I want to put peak performance first, the JoeZ intake pipe was the winner at the end of my research. Even though the 3IS F-Sport intake pipe has a slighter larger 3.00" inner diameter compared to the 2.75" JoeZ intake pipe, the higher air velocity and less turbulence of the JoeZ intake pipe allowed the engine to breath better and therefore make more potential power at peak RPMs.

 

Nice work. I'll see if I can find the Dyno results I was talking about and post up here in the same place.

I'm curious though... since the MAF is mounted up on the air box before the intake tube, does the MAF gs/grams per second still show accurate results based on the modifications you've made?

Anyone else have input on this?
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From what I've seen, the MAF g/s readings from a stock engine is around 220 g/s. As more modifications are done to the engine to speed the process of expelling the exhaust gases, the higher the potential MAF g/s.

Without modifications to the intake manifold, throttle body, etc., horsepower and MAF g/s gains from an intake mod will be minimal but based on the multiple datalogs I've collected the past few months with these two pipes as my samples, there were consistent (albeit small) air flow gains to be had with the JoeZ pipe over the stock 3IS350 F-Sport intake pipe.