De-snorkeled my Box 5 minutes max

[Boxtaboy]

I agree with JFP, in that I think desnorking does make you lose a little power. I was desnorked for a year, and always noticed that at highway speeds over 60+mph, it always felt like I had less power with the snork out. My personal layman's theory is that the snork was designed with the curved, trumpeted opening (which sits closer to the grille opening) to better facilitate airflow into the airbox, giving it a smoother and less turbulent flow into the airbox. With the snork out, there is a void in that area that includes all these waffled edges at the rear section which cannot help airflow into the airbox. Couple that with the fact that the remaining opening after pulling out the snork leaves a straight edge whereas the snork used to have a curved opening, and the flow must be worse than before, IMO.

That being said, ultimately, after putting the snork back in, and feeling like the power had come back at speed, I still really disliked having the snork back in place because there is a remarkable difference in the way the car sounds with the snork back in.... it was just too quiet for my liking, and I soon was back at pulling that snork out. This time, however, after pulling out the snork, I took a dremel to the remaining straight edged opening at the rear section, and sanded it into a curved opening to simulate the curved opening of the snork (and then vacumed out the sanded out bits prior to putting it back together). You can't see it too well in the crappy picture I took at the time, but I now have a curved opening into the airbox. Not sure if it helps or not, but I do love the sound of the car desnorked, and if it means a 2hp loss as JFP shows, so be it...at least I can hear the sweet growl of the intake while I'm going slower, and getting less mileage.

Desnorked and dremeled remaining opening:

[JFP in PA]

The baffle’s function is misunderstood; it is there so that the car meets the ridiculously stringent Swiss noise laws, the same reason for the overly complex Sports Exhausts design, with its valves and speed controls as a factory installation. The Swiss have very tight requirements on how much noise a car can make and certain speeds and under certain conditions; the so-called “snorkel” is there to comply with that requirement. It’s rather peculiar design speaks to meeting the sound level without disturbing the flow of the rest of the intake system, which obviously works. When it is removed, the sound level rises, but the intake system is no longer “optimized”, so performance suffers slightly.

It would be interesting to see if gains could be made by totally redesigning the runner system to operate without the baffle, but that would require a lot of flow bench time at a minimum……………..

[Boxtaboy]

Originally Posted by JFP in PA

The baffle’s function is misunderstood; it is there so that the car meets the ridiculously stringent Swiss noise laws, the same reason for the overly complex Sports Exhausts design, with its valves and speed controls as a factory installation. The Swiss have very tight requirements on how much noise a car can make and certain speeds and under certain conditions; the so-called “snorkel” is there to comply with that requirement. It’s rather peculiar design speaks to meeting the sound level without disturbing the flow of the rest of the intake system, which obviously works. When it is removed, the sound level rises, but the intake system is no longer “optimized”, so performance suffers slightly.

It would be interesting to see if gains could be made by totally redesigning the runner system to operate without the baffle, but that would require a lot of flow bench time at a minimum……………..

I've heard that theory about the snork being placed there to meet the stringent sound limitations in certain countries, but I then wonder why that type of snork tube is inserted in many different types of cars, even domestic ones.... you find them in the older air cooled 911s, in Mazda pickups, all sorts of cars....they all have snorks leading to their intakes. Therefore, I would think that there was a reason for them being there (maybe one function is to further quell sound), but there has to be another benefit to them, no? In fact, I would bet that you could get the Boxster up to higher speeds without even realizing the louder noise of the desnork because the extra growl from the desnork doesn't even come on until after 4k+ rpms really. This is why I don't think the snork is there solely for the purpose of noise abatement.

[JFP in PA]

Originally Posted by Boxtaboy

I've heard that theory about the snork being placed there to meet the stringent sound limitations in certain countries, but I then wonder why that type of snork tube is inserted in many different types of cars, even domestic ones.... you find them in the older air cooled 911s, in Mazda pickups, all sorts of cars....they all have snorks leading to their intakes. Therefore, I would think that there was a reason for them being there (maybe one function is to further quell sound), but there has to be another benefit to them, no? In fact, I would bet that you could get the Boxster up to higher speeds without even realizing the louder noise of the desnork because the extra growl from the desnork doesn't even come on until after 4k+ rpms really. This is why I don't think the snork is there solely for the purpose of noise abatement.

Actually, it is for noise abatement, and different OEM’s handle the issue in various ways. We currently have a Nissan product in the shop that has two factory options: A really slick cold air system and a large diameter, low restriction stainless steel exhausts system. Because the car came from the factory with these, there are two small decals on the radiator support noting that “the car is not legal for export to certain European countries”, because both the intake and exhaust fail to meet “TUV noise standards”. The non option version of the same car has a plastic box in the intake system with a similar baffle to the one on the Boxster inside of it, if you disconnect the box; you get a pronounced intake “roar”, much like the cold air system has. Interestingly, the optional cold air system, which while simple, is beautifully designed, adds 8-10 HP at the wheels, and the exhaust another 10-12 over the standard stuff, so the addition of these does make a significant difference.

The Swiss must drive the OEM’s nuts with this stuff………..

[Boxtaboy]

Originally Posted by JFP in PA

Actually, it is for noise abatement, and different OEM’s handle the issue in various ways. We currently have a Nissan product in the shop that has two factory options: A really slick cold air system and a large diameter, low restriction stainless steel exhausts system. Because the car came from the factory with these, there are two small decals on the radiator support noting that “the car is not legal for export to certain European countries”, because both the intake and exhaust fail to meet “TUV noise standards”. The non option version of the same car has a plastic box in the intake system with a similar baffle to the one on the Boxster inside of it, if you disconnect the box; you get a pronounced intake “roar”, much like the cold air system has. Interestingly, the optional cold air system, which while simple, is beautifully designed, adds 8-10 HP at the wheels, and the exhaust another 10-12 over the standard stuff, so the addition of these does make a significant difference.

The Swiss must drive the OEM’s nuts with this stuff………..

Cool, then all I have to figure out is a way to block out the waffle voids in my intake area, design a bigger curved scoop, and I'll have put that 2hp back into my car!

[JFP in PA]

Originally Posted by Boxtaboy

Cool, then all I have to figure out is a way to block out the waffle voids in my intake area, design a bigger curved scoop, and I'll have put that 2hp back into my car!

Intake systems can be funny things, they often respond rather differently than you might expect. We once were running an engine on a dyno cell stand (no car), and made pulls with and without an air filter, only to find it made more power with the air filter in place. One would assume that without the filter, the system should flow more air, but while the A/F ratio remained pretty stable, output dropped. It liked the filter, go figure……………..

[mptoledo]

wasn't the other reason for the snork to keep debri out? I have heard the lit cigarette example more than once. I noticed the small pan at the front of the snork looks like it is to keep out stuff.

Either way I will do my own unscientific analysis and let you know. I did read boxtaboy's reply on another thread as I was researching it. I can't see how letting more air in a less restrictive manner can cause a reduction in HP or MPG. Oh, well as jeff has said on numerous occasion, this dead horse has been beaten enough. Thanks for the input.