air restrictor mod

<div></div> <div>Decided to have ago at the air restrictor mod this evening, managed to remove the cover and restrictor plate no problem.</div> <div></div> <div>Looking at the plate it’s clearly there for a good reason, mainly to stop a lot of air borne water going straight in to the engine when it’s raining. </div> <div></div> <div>If no plate is fitted a fair amount of water that bounce off the air intake grill then precede to go into the filter at the end of the oval tube. </div> <div>When driving air is sucked in to the engine and when driving in the rain so will a fair amount of water droplets too. This is backed up by the size of the channel that runs along the right hand side and bottom of the restrictor plate, it’s over 20mm high and leads directly to a drain hole. Much larger droplets are sucked in without a restrictor in place, the grill acts as a prefect defector to bounce water in to intake in my view.</div> <div></div> <div>I’m definitely leaving it in position </div> Edited by - zornet on 05/14/2006 10:49:02 AM

Wow, that is first. I was fairly confident that we didn't need to even use the mesh screen. So I am assuming that you left it in and put it back together? I will consider what you have said. I was going to do mine this weekend. Thanks for sharing your thoughts. Russ

Porcheplayer - You’re not of the belief that the 20mm channel you mentioned is actually directing air to the oval tube/snorkel rather than as a drain. I feel its channeling the remaining air that’s not blocked by the Restrictor to the intake. In my book the Restrictor is there for liability blockage of a HOT cigarette-ash, only. zornet

This topic has been discussed in detail and it has been determined that the water is not an issue.

I've been toying with the idea of doing this myself. I have been waiting to see if someone could get a definitive answer from somewhere as to whether the plate blocks water or cigarettes. Is it possible to actually contact an engineer at Porsche to answer this once and for all? Tony

My suggestion is to read the detailed discussion on this from the prior post and make your own decision. I read the info, weighed the facts, did my own analysis and De-Snorked. I driven in some pretty bad rain and no noticable issues. Anyone from Porsche official will not recommend removal.

Tony, Getting approval from Porsche would be nice, but as PACayman said, not likely. Liability issues would kieep them from endorsing such a mod I am sure. I am more worried about breaking the clips than having water get in where it could do any harm. Russ

After considering the design, I decided to leave the plate in place, sure the air flow is better and I can see why Kman has had stronger Dyno results, but it's obvious to me the plate will stop loads of water going into the filter.It's clear the channel is not designed to have any effect on air flow and would be in complete different position and design if it where, the channel ends right above the drain hole too and is only on the rear if the plate. The whole area behind the intake grill is made for a flexible rubber material to ensure water is guided down to wards the drainhole, I've read all the other threads and decided I didn't think water would be a problem, but I'm not going to risk getting leaves, tabs ends and larger water droplets down to wards the filter. Not sure the extra water which will be sucked in would damage the engine anyway, but why risk it. I'd lovesome free HP but the route is to direct without the plate in position IMO. Edited by - Porcheplayer on 05/12/2006 09:16:52 AM

KaiserSozay, A Republic F105 had water injection. It still took two miles to get airborne. And someone once said that if a runway was built around the entire equator, that Republic could build a plane that would use it all!!! Water does suppress detonation. I wonder if the electronics would negate the advantage???

Russ, I broke one clip and it in now way impacts water getting in. In fact I used the De-Snork thread to accomplish and did NOT break the clip. I actually broke the clip when I dropped the piece!! The De-Snork direction and diagram of the clip is great. Go for it!

Russ and others, I realize you are correct, Porsche is not about to O.K. such a mod. I wonder if it might be possible to fashion a much smaller baffle to deflect rain which could sit on top of the mesh? There are some very industrious people in this club. Tony

Hi kaiser I haven't had the opportunity to inspect the plenum, but looking down the tube in situ, I can see the filter at the end, posters mention an upward direction of air flow at the end of the tube, but it's possible to see part of the filter looking down the tube. Don't forget the engine creates low pressure in the tube and any lighter particles will be sucked directly to-wards the filter. Extra water in the engine can't be a good thing, seen as it's an known varible and Porsche has designed the plate to stop direct air flow. Agree with you about the stocking/mesh solution. You'd get max air flow and minimum detritus

</blockquote>

<blockquote id="quote">quote:<hr id="quote" noshade="noshade" height="1" /> <div style="MARGIN: 0in 0in 0pt">Porcheplayer[/quote] - You’re not of the belief that the 20mm channel you mentioned is actually directing air to the oval tube/snorkel rather than as a drain. I feel its channeling the remaining air that’s not blocked by the Restrictor to the intake. In my book the Restrictor is there for liability blockage of a HOT cigarette-ash, only.[/quote]</div> <div style="MARGIN: 0in 0in 0pt">.[/quote]</div> <div style="MARGIN: 0in 0in 0pt">zornet /fckeditor/editor/images/smiley/MWPX/gossip.gif[/quote]</div> <hr id="quote" noshade="noshade" height="1" /> I stand corrected, memory failure, I pictured from memory the Air Restrictor, and just took a view in person, the channel is on the wrong side too funnel air to the intake. zornet

Water actually increases the horsepower and is in no way harmful - unless you are simply dumping it directly into the intake (aka sinking in a lake). Water droplets hit the filter element and act as a evaporate cooler, lowering the temperature of the intake air... Secondly, I raced motorcycles for quite some time and their direct ram-air snorkel (front of the bike) was a 'clear shot' of about 6' worth of travel for any and all rain to be sucked in...frankly, never made one lick of difference in my tenure on sport bikes. Cars have had ram air since the 50's with snorkels leading straight to all that rain-water and it has never fouled any engine of mine. Water (in reasonable amounts) is simply a non-issuefor an ICE. Paul

Many turbo kits out there for many cars have a water injection type system that actually sprays water into the intake tube. The reason this can be good is because the presence of water in the intake air can reduce detonation. Shane

I'm aware of water spray systems also, but its not in any way the same as having a unmeasured amount of water drawn into a modern electronically controlled Porsche engine. The best engineers at Porsche clearly think the plates required and so do I.

The movement of the Pistons creates a negative pressure in any vessel that's linked to them, I.E, the intake tube and outside the car.Air is drawn into the Piston on the down stoke. The higher the revs' the lower the pressure, it's not something that would be easy to replicate or test. I'm not saying it excessive water would be a problem, but I don't know andneitherdoes any one on this board for sure, but why risk it and remove a part that Porsche engineers have designed, which incorporates water channels and is constructed in a way and from materials which are used in wet areas, the rubber surround is a high gloss coated material that's only used to in very wet areas and has properties which allow no water to ingress or remain on the surface. Edited by - Porcheplayer on 05/14/2006 10:28:00 AM

Pardon my stupidity but once in a while a fan kicks on and a significant vacum seems to form around the intake grill being discussed. That negative pressure must cause some H2O and debris to be pulled in - will your mod make any differrence under that condition?

The fan is on the right side (passenger side / #2 side). It is a fan that kicks on to cool the engine. It isn't on the actual 'intake' side. The side the modification is done to is the left side (driver's side). Shane

Geez I get back into town and a whole new thread on this mod erupts, would be nice to keep this with the existing very long thread that alread exists on the topic, too bad merging threads is a PIA and manual in this software currently or I'd do it in a heartbeat. Please do me a favor and respond in the other thread if you feel the need to respond. As far as an 'engineered' part, none of the 986 Boxsters have this restrictor plate, so it is pretty obvious that this was designed more to keep cigarette butts out than water or anything else and certainly isn't there for performance reasons. However, I fully support anyone who does NOT want to do this to their Cayman . This mod is entirely optional and each of us needs to feel comfortable in our decisions. There is no right and wrong here.

Notice that the part being removed is not an air restrictor by Porsche definition, rather it is an impact absorber plate (see diagram from parts manual). Maybe Porsche found out from boxster experience (or because of grill orientation change) that this impact plate was needed. Is it there for ONLY smoking items or for other debris?? Would screen door fabric be equally effective, while retaining better flow of air?? Is the plate there to chaneg the sound? In that Cayman book, they talk alot about how the car was to have a certain sound both in the car and out of the car ...

I still hold to my theory that it is there to deflect objects that would otherwise get to the air cleaner. Thinks like rocks and small bits of trash. Those very possibly could work theirselves past the air cleaner and I suppose into places that they could do damage. Are the gains enough to risk that. That is an individual choice.

Wonder is JackWood still working on this? Have been htinking about the possibility of the holes in the mesh being slits or louvers that, at an angle could deflect debris and water downward, still let the air be sucked in more freely than stock. jm

<blockquote id="quote">quote:<hr noshade="" height="1" id="quote" /> I still hold to my theory that it is there to deflect objects that would otherwise get to the air cleaner. Thinks like rocks and small bits of trash. Those very possibly could work themselves past the air cleaner and I suppose into places that they could do damage. Are the gains enough to risk that. That is an individual choice. <hr noshade="" height="1" id="quote" /></blockquote> Santa Fe, I'm with you. I fully believe that the impact absorber plate is there to prevent little sharp rocks, pieces of glass, hard stuff other than air and a little moisture, from getting to the air filter element. Porsche tested this car all over, in all kinds of conditions: sand, ice, gravel, rain, etc. And I suspect that direct entry of those hard and sharp substances can damage the air cleaner by smashing pleats, making cuts, etc. And after a period of time (say sometime BEFORE the Porsche recommended service interval), the filter would be admitting unwanted crap into the engine. Who knows just how much crap. Certainly, any crap can't be good near fast moving metals ... And since getting to the filter isn't as easy as in a 911 , the owner probably wouldn't get around to it for inspection/replacement at a shorter, unrequired service interval. Is that 'extra' protection needed? It would seem to me that the impact absorber plate is more valuable OR at least as valuable for engine protection as a clear bra is for paint protection. And I suspect more so. IMO. Edited by - fmarshall on 05/24/2006 08:17:29 AM Edited by - fmarshall on 05/24/2006 08:20:16 AM