So I drilled
funny when i switched out the stock filter for a HKS unit i didnt even notice the fins. i heard from somebody that the F-sport units are designed and made by AEM. not to throw anything onto the fire but more noise doesnt always mean more power. you'd almost be better off wrapping the pipe well if you swtiched to one with thermal wrap to keep the incoming air as cool as possible.
Lead Lap
Joined: Sep 2005
Posts: 588
Likes: 14
From: Charlotte, NC
i dont know if there is room, ill take a look on friday when my car is up on the rack getting sway bars put in. but doing that would mean putting it near to the ground and running the risk of getting water into the pipe. does anyone know if aem makes a universal water bypass valve for intakes? swtiching the main intake pipe might be better, plus im thinking about adding thermal wrap for mine, to keep things cooler.
so any problem with the extra holes on the front of the air box yet? did you guys feel any loss in power due to introducing hot engine air from the extra outlet? I took the box out and was about to cut the hole but then I discovered that there were some dry water spots all over the box. Is this going to be a problem later on because water could actually get in the system now. the inside of the box is dry and no water spot but the outside of the box is full of water spots. I only wanted more sound and really don't care about any gains just worrying more about losing horses and torque.
so any problem with the extra holes on the front of the air box yet? did you guys feel any loss in power due to introducing hot engine air from the extra outlet? I took the box out and was about to cut the hole but then I discovered that there were some dry water spots all over the box. Is this going to be a problem later on because water could actually get in the system now. the inside of the box is dry and no water spot but the outside of the box is full of water spots. I only wanted more sound and really don't care about any gains just worrying more about losing horses and torque.
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man don't even worry about that .005 hp loss with the holes, is all about the sound!! i have a Joe Z.. then i make some holds today on my stock air box like the 1st pic darn is sounds nice. JUST make that hole is sound really good but after 3.5 RPM like the F sport.
Rookie
Joined: Dec 2008
Posts: 58
Likes: 0
From: ca
Hey I did something similar, except i drilled a single 3-1/2 in hole (use a real hole saw) to the bottom half. looks more cleaner than making alot of little holes. I also removes the carbon filter on the top half and smooth out all the ridges (took forever).. you do not loose 1 hp by removing the carbon filter, by removing the carbon filter you get more volume of air into the intake, thats just plain engineering facts. the carbon filter is there for emission purposes i assumed. 
i kept the hole that i drilled out, put some wing nuts on it, and can always used it to cover the hold that i made. i saved the carbon filter just in case if i will ever need it.
i kept the hole that i drilled out, put some wing nuts on it, and can always used it to cover the hold that i made. i saved the carbon filter just in case if i will ever need it.
Last edited by kimban; Apr 6, 2009 at 03:21 PM.
Hey I did something similar, except i drilled a single 3-1/2 in hole (use a real hole saw) to the bottom half. looks more cleaner than making alot of little holes. I also removes the carbon filter on the top half and smooth out all the ridges (took forever).. you do not loose 1 hp by removing the carbon filter, by removing the carbon filter you get more volume of air into the intake, thats just plain engineering facts. the carbon filter is there for emission purposes i assumed.
Hey I did something similar, except i drilled a single 3-1/2 in hole (use a real hole saw) to the bottom half. looks more cleaner than making alot of little holes. I also removes the carbon filter on the top half and smooth out all the ridges (took forever).. you do not loose 1 hp by removing the carbon filter, by removing the carbon filter you get more volume of air into the intake, thats just plain engineering facts. the carbon filter is there for emission purposes i assumed.
i kept the hole that i drilled out, put some wing nuts on it, and can always used it to cover the hold that i made. i saved the carbon filter just in case if i will ever need it.
i kept the hole that i drilled out, put some wing nuts on it, and can always used it to cover the hold that i made. i saved the carbon filter just in case if i will ever need it.
Besides, the size of the tube for any ISx50 is far greater than it need be to make a measly 306 hp at the crank. NASCAR makes nearly 500 hp with four 25.4mm holes for a total area of 3.142 in^2 in their restrictor plate engines. The ISx50 have a 3" intake yielding 7.069 in^2, or over twice the cross section of the four little holes NASCAR uses to make nearly 500 hp.
What does this mean? The intake tube and airbox isn't the restriction for this engine in any way, shape, or form. You could reduce it to two inches and you'd still have enough cross section to make pretty close to 500 hp. So even at 2" it's still 63% larger than it absolutely must be to make 306 hp. It could be even smaller for the 250.
Stop believing the hype. If your goal is more noise, cut all the holes you want, but you're not going to get any more power out of it.
I am an engineer, and doubt that there is any scientific significance to the repeated 1 hp drop on the dyno by removing the carbon filter, but I don't believe for a second that cutting holes in the air box will increase power.
That said, I've really considered doing it for sound! However, if I do decide to cut some holes, I would glue thin / flexible plastic over the holes to allow sound to pass without allowing air to pass.
I cut a hole just like the F-Sport, in-front of the air box, about the same size, and there is not alot of noise before the 3500 RPM. But after 3500 RPM, it growls and sounds very pleasing. Wish the sound would come at around 2700 though cause I never drive that fast to hear it that long. It will growls and then the engine noise will kick in at about 4500 RPM and the end. Even if you hold it at 4000RPM, just engine noise not intake. Very pleased with the sound at 3500 RPM though but it does not last long.
Rookie
Joined: Dec 2008
Posts: 66
Likes: 0
From: WV
Joe Z vs K&N
I've read this whole thread trying to figure out which intake to go with. Only one person said he liked his K&N.
Can a JOE Z with a drop in aftermarket hi-flow filter match the 11 hp gain of a K&N Typhoon? K&N are pretty good with they're R&D. See attached link http://www.l-tunedparts.com/product/?id=2804
Looks like the best of both worlds, sound (I've used them on other cars) and hp. Comments?
Can a JOE Z with a drop in aftermarket hi-flow filter match the 11 hp gain of a K&N Typhoon? K&N are pretty good with they're R&D. See attached link http://www.l-tunedparts.com/product/?id=2804
Looks like the best of both worlds, sound (I've used them on other cars) and hp. Comments?