De-snorkeled my Box 5 minutes max

[mptoledo]

Probably the easiest mod yet. I know this is remedial to most of you. I do this for people like me who aren't a true mechanic. Hopefully they can learn from my mistakes and save a few $$$

WHY?: Mostly sound. You can judge for yourelf. Some have claimed increase of HP of 5-7 and moderate Torque gain. I am still looking for some hard proof.

Tools: phillips screwdriver, maybe some paper towels

Difficulty: 1 out of 10 Cake!!!

Time: About 5 minutes.

MY car: 2001 "S" 3.2L 62k miles

Here's the way I did it: You can follow this website as it has great pictures.
http://www.pcars.us/10min-boxster-de-snorkel-hack-t3401.html
1.) Remove screw on driver side air vent and remove
2.) Remove Black(or painted) grill by gently pulling plastic arms forward out of their clips. Be gentle as they are a little fragile.
3.) Grab the long black tube and rock it side to side and pull hard until it comes out. there are no screws holding it in, just a small clip on the inside top of it. You can try pressing the top, but I just yanked it out.
4.) Optional, I sprayed some windex on a paper towel and cleaned out the inside.
5.) Put it all back together and go test drive it.


Projects completed:
1.) Serpentine belt...........$25 Gatorback w/ac
2.) Sparkplugs..................$42 Ngk-Ix-Iridium
3.) Radio replaced............$225 JVC HD50 (BB install)
4.) Tires............................$700 Sumitomo III Local shop
5.) Oil Change/air filter.....$94 catro syntec 10W40,napa gold,K&N air
6.) Speakers....................$143 Infinity Kappa F=4", R=6x4 plate
7.) Throttle body clean.....$5 Throttle body cleaner
8.) De-snorkel..................$.10 A few paper towels

Projects to do:
fuel filter
Battery (spring).

[JFP in PA]

Not to deflate your enthusiasm, but why bother? This mod has been beaten to death on multiple sites; yet those that have bothered to test before and after have found that most cars lose power as well as gas mileage with the baffle out; so, like most headers, all you get is noise. It’s your car, so do as you please, but be aware that not all mods have a positive outcome……..

[mptoledo]

Originally Posted by JFP in PA

Not to deflate your enthusiasm, but why bother? This mod has been beaten to death on multiple sites; yet those that have bothered to test before and after have found that most cars lose power as well as gas mileage with the baffle out; so, like most headers, all you get is noise. It’s your car, so do as you please, but be aware that not all mods have a positive outcome……..

I haven't read anything about losing gains, except an article back in 2005. It was discussing if Hot air would get in and cause a decrease in power. More post have supported it than have condemed it. But as i said in the op, "this mod is mostly for sound".

Now you have peaked my interest that this may be detrimental to mpg and power. I need to do some research on it. I see the potential for power gains as you have less restrictive air flow, but then the other side has merit with their hot air versus cold air theory.

[JFP in PA]

Originally Posted by mptoledo

I haven't read anything about losing gains, except an article back in 2005. It was discussing if Hot air would get in and cause a decrease in power. More post have supported it than have condemed it. But as i said in the op, "this mod is mostly for sound".

Now you have peaked my interest that this may be detrimental to mpg and power. I need to do some research on it. I see the potential for power gains as you have less restrictive air flow, but then the other side has merit with their hot air versus cold air theory.

You are not “losing gains” just losing slight HP and more particularly gas mileage. This mod will also do nothing to change the temp of the intake charge, that would require other modifications. You may want to check the archives over at PPBB, there have been multiple threads on this, all came to the same conclusion, it is not a positive move unless all you are interested in is more noise.......... If memory serves, one of the catch points started when those that removed it noticed a slight drop in gas mileage, which initiated the before and after testing. Also believe is has been covered, ad nauseum, on RennTech as well……………….

[ChefCarnivore]

Thanks for the post. I always wondered what desnorkeling meant. I like the sound the car makes now. If it improves performance I'm not sure.

[mptoledo]

The sound after desnorkling is pretty cool, especially at the 3000k range and up. I have read 100's of post in numerous threads and it seems the mpg loss mostly comes from people changing their driving habits to here the new sound of their engines. I have only seen 1 guy who claims his mileage went to 10mpg on a 40 mile trip. I consider that post worthless and without merit as there is no way you will drop 40% to 50% in mileage.

I still haven't seen any concrete data, just opinions. For now I will keep it off as the sound is pretty cool. I do monitor my MPG on every fill up and will report my findings.

[mptoledo]

Ok, I found this post on here from a guy who dyno'd his 2001 "s".
He found a 5.3 hp gain and 2.7 torque gain.

He owns his own dyno and has great credentials. " I am an engineer, tuner and enthusiast, and have designed parts for NSXs, S2000s, and even factory supported FWD drag race teams. My race program involved many secured world records...but I digress."
Finally: Dyno charts of de-snorked 986S!!!

Now, the dyno doesn't test the car under true driving conditions and wind speeds @ 50mph. So take the info as you want. I am still searching for the truth, as I know its out there! Most the claims of loss of mpg came from the 987 not the 986.
exerpt "Wow..this is so sad...so much happened on the board while I spent more time beating my poor S on the dyno today. I have repeated the results on 17...yes 17 passes with and without the "snork". The data remains the same. For what it is worth, this mod produces 4.6~5.5whp at high rpms. Whew!"


I am not trying to blindly support my decision. If i am wrong I would be the first to admit it. I just don't take some other guys response of "it felt like i loss power" as a scientific conclusion.

[JFP in PA]

Sorry, but I still don’t buy it for multiple reasons. Interestingly, he ran his tests on a hub design dyno that is well known for always giving considerably higher readings (10-12% are not uncommon) than conventional roller units in side by side runs. I know the manufacturer claims this is because it’s unique design which “eliminates the “roller effect”, but at the end of the day, the rollers are in much wider use. In any case, while I am not going to challenge the veracity of his test; I can tell you that two different cars that I watched being tested showed a slight, but measurable drop in HP and Torque when tested on the rollers. When combined with consistent comments that multiple cars saw lower gas mileage with it out, but recovered the mileage when it was reinstalled; I think you are “tilting at windmills” here……………

[mptoledo]

Originally Posted by JFP in PA

Sorry, but I still don’t buy it for multiple reasons. Interestingly, he ran his tests on a hub design dyno that is well known for always giving considerably higher readings (10-12% are not uncommon) than conventional roller units in side by side runs. I know the manufacturer claims this is because it’s unique design which “eliminates the “roller effect”, but at the end of the day, the rollers are in much wider use. In any case, while I am not going to challenge the veracity of his test; I can tell you that two different cars that I watched being tested showed a slight, but measurable drop in HP and Torque when tested on the rollers. When combined with consistent comments that multiple cars saw lower gas mileage with it out, but recovered the mileage when it was reinstalled; I think you are “tilting at windmills” here……………

Again, I am still in the wait and see camp. I check my MPG after every fill up. I do like the sound with it off. Even using an inferior dyno, it should give a consistent before and after reading even if they are both high. Enough of that. As I said in the OP, HP and torque gains(if any)are negligible and aren't the reason I did this.

I am glad you brought up the MPG issue, as to me that is way more important than any small gains or losses in hp or torque. I will definitely keep an eye on them over time and report my findings, as unscientific as they may be. I still think most people rev up and wind out through the gears more to hear the noise, which makes sense why they would see lower mpg.

[JFP in PA]

OK, I went and looked up one of the guys that ran the test I watched on the rollers and he sent me the following data on multiple runs, with and without the baffle;

***18 Jul Stock no mods ***
RF-001 258.31 bhp 220.54 ft/lb
RF-002 258.21 bhp 221.92
RF-003 258.44 bhp 221.03

********* 18 Jul De-Snorked runs *****
RF-004 256.95 bhp 217.82 ft/lb
RF-005 256.17 bhp 218.46
RF-006 255.95 bhp 218.91
RF-007 256.19 bhp 220.00

Doesn’t look very promising on the performance side, but it was noisier……

I have no idea about the source of the MPG change, so you could be correct in that it results from "too much right foot"..........

[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.

[Boxtaboy]

Originally Posted by 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.

I think if you want to do an unscientific analysis, you can just do some timed runs on the freeway (where the airflow will be important), from 50-90mph, for example, with and then without the snork. That, I think, would be a pretty good measurement of what the snork actually does. Personally, I think you'll find that the snork will help your times, but I could be wrong. I hope I'm wrong, cause my snork is out. LOL

[JFP in PA]

Originally Posted by 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.

Nope, it is a noise baffle. If you really stop a moment and look at the opening in the body with the grill removed and the “snorkel” still in place, a whole lot of stuff can get passed it, so as a debris preventative, it would be pretty poor; you’d be a lot better off with some simple mesh for that purpose………….

[mptoledo]

Originally Posted by JFP in PA

Nope, it is a noise baffle. If you really stop a moment and look at the opening in the body with the grill removed and the “snorkel” still in place, a whole lot of stuff can get passed it, so as a debris preventative, it would be pretty poor; you’d be a lot better off with some simple mesh for that purpose………….

No, I pretty much think your wrong on that. The cup on the bottom is to keep debri and water from getting sucked in. Now how effective it is, well thats another question. If you really look at it, its obvious the cup is there for a reason, to keep crap out.

If you guys want to keep going, I have also read the for any increase in air flow your ecm need time to adjust. Just like pedro says when you install his techno flow thing. All the dynos I have seen have been negligible gains and the only one that reset his ecm was the one who claimed 5 hp gain after 17dynos.

Now I feel like I am defending it, when that was not the purpose. Its like one of those highschool debates that you have to take a side you care nothing about. People have asked about de-snorking and I thought I would try it.

There isn't enough evidence wither way to support a conclusion. I don't race so the HP gain or loss of + or - 2 hp doesn't matter. I would be concerned about mpg loss, but it makes no sense, as common sense dictates that you will get more air flow. The only things I can think of that might go against that is if the snork some how lessened the amount of turbulence, like pedros claim of his thing, and if hot air was sucked in rather than cooler air. I would lean towards the latter.