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jclocatelli said:
And again the snorkel is for just in case shit happens.... Meaning I take the van to Mexico a lot and sometimes when it rains Bridge's falls down and I have to cross an arroyo. But the best thing of it is, when I'm sitting at the border waiting to cross back for three hours I am in bumper-to-bumper traffic... I am not collecting the hot air from the exhaust and the hot asphalt so there stays cooler.
DETAILS! PIX! IDEAS! Please! I just spent an assload of money for what may or may not work. It'll work. Love that snorkel of yours :thumbup: I want to make one not so much for river crossing but for cooler, cleaner air.

Cool video! Where is that? I wanna go there after it rains.
 

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OK, so here's my input.

Mostly I wanted a snorkel for cold air intake since I'm not a fan of the hood scoop or holes in the bumper etc. I also really like the look of a snorkel having driven offroad vehicles exclusively since day one. Since I was already in the process of cutting and drilling a million holes in my van I figured what the hell, might as well make a nice big 3.5" hole in my fender too!

Here's the progression, done simultaneously with my aluminum body cladding mod.

I wanted to use the largest pipe practical, so I chose 3" schedule 40 black ABS pipe that's easily available at the hardware store. Schedule 40 3" pipe has a 1/4 thick wall, so the pipe O.D. (outside diameter) is actually 3.5". I used a Grenlee 3.5" conduit punch that I had bought used on ebay when I built my roof rack (used it for the portholes):



I used a template and tried to find a location that was flat and far enough away from the blower motor:



Spending an hour at Home Depot can really spark some ideas. Look in all the bins, pull stuff out and lay it on the ground. You will go into the store with an idea in mind but once you see what is available to you I guarantee that idea will evolve fast. I basically I built my prototype right there on the floor of Home Depot. I was very selective but I still spent $185 on plastic pipe and fittings! It adds up quick! I came home with this:



As far as I have seen on the internet the passage through the body seems to be the weakest (ugliest) link. For DIY snorkels most people just cut a nasty hole in the body and feed a solid pipe through it. Hey that's great if you can make the edges of the hole look nice and make it feel solid. I wanted something better.

I wanted the ability to remove my snorkel easily so a mounting base seemed the best way to do that. I didn't have a clue what I was going to use for a base until I saw "toilet flanges" in a bin. I decided I was going to use a "toilet flange" or "closet flange" as a mounting base for my snorkel because it was very sturdy and despite the large diameter would fit on the backside of my fender. It was also thin enough to easily fit in between the fender and sub-fender. This would not not only give me a nice firm mounting base but also the pipe part of the flange would come through the hole and leave only a very small gap around it that I could seal with urethane.

I made a template for the O.D. of the flange and made sure to it would not overlap the indentation of the body lines and could still match up to the nice flat spot I had chosen on the inner fender wall:



It's nearly impossible to match up the templates from the outer and inner fenders. Once I had an idea of where the flange would fit I drilled a 1/8" diameter pilot hole from the inside of the engine compartment. You can see the drill bit in the space between the inner and outer fenders (Note: grille removed):



I then removed the outer fender. It's not as challenging as you may think and I believe it's necessary if you want to do a good job with the hole placement. It's also not an option if you're using the toilet flange and planing to install it from the backside of the fender. You could do it on the outside but it would really look like shit and plumbers will laugh themselves into a ditch as they pass you on the road. Once I had a rough idea of the centering between the two fenders I double checked that my toilet flange would still be in a good spot.

After the outer fender was removed I started cutting the inner fender hole:











Then the outer fender hole:







Checking my flange placement:



Because the inner and outer fenders are not parallel there will be a problem with diameter. The inner panel is now oval so a straight pipe will not feed through:



Some massaging with a file is necessary.

Be sure to paint the bare metal edges:



If you were to mount the flange outside the fender it would look something like this...not too pretty:



I installed it on the backside:







I used stainless steel hardware:



When installed on the backside and pipe fed though the hole and into the flange will look nice and clean:



Here you can see the relation between inner and outer fenders and the clearance with the flange:



You can see how I had to open up the inner hole for more clearance:









Basically what you have after mounting the flange is a socket for a 3" pipe. You can then add some sort of fitting to the outside and run your pipe. I added a ~6" section of pipe and welded it (with pipe glue) in place. This gives 1.5" sticking out for a fitting and a few inches inside to attach a hose:













You do need to trim the inside of the flange socket a bit to get the pipe all the way through since they are tapered fittings. A dremel with sanding wheel works great for that.

There are various ways of bending the snorkel pipe to conform to the body. I tried a few and failed with every method. Bending 3" schedule 40 pipe is definitely not easy. Ideally you have one of those $500 heated blankets that plumbers use. If not perhaps you can try to disassemble a toaster oven and use the heating elements to heat the pipe. Or you can buy some flexible hose like I did as plan Z after failing miserably with plans A through Y of pipe bending.

So now onto the pillar mount...

I wanted to weld tabs to the pillar but I was worried I would either heat up the butyl rubber holding the window and melt the seal or that I would crack the window. I decided on pop riveting tabs to the pillar. It's not as solid but at least it can be undone:





I welded a bar in between because I couldn't think of any easy way to attach the tabs to a round pipe. The bar would allow me to wrap a hose clamp around the whole thing:





Attached to the pillar (I still had not figured out how to bend the pipe at this point):





As mentioned I was unsuccessful bending the 3" pipe. The outer surface would start to melt and bubble before the inner parts were heated enough to be flexible:



So plan Z involved super heavy duty smooth inside with PVC rod wrapped on the outside hose from McMaster-Carr (it's hose used for coupling between pipes):

hose.JPG


This hose is not flexible at all. It will curve nicely to the side of the van but forget about 90* bends etc.

I cut a piece to use as the lower section of my snorkel. I then plasti-dipped it black:



I sanded the ABS plastic section of the pipe to prep it for truck bed paint and used a dremel to smooth the mold leftovers and writing off the elbow. The less this stuff looks like plumbing fitting the better it looks on your van:





All the outer pieces ready to install:



Note that I slit the fittings so the hose clamps would act as a clamping chuck. I slit the fitting back enough for the clamp but not far enough back to allow the fitting to take in water. The slip fit is 1.5" deep for the pipe socket, I cut my slits about 3/4" back:



Slipping the fitting onto the base (it's not on all the way in this pic):







I bought my snorkel head on Amazon for something like $35. Once I had it in hand I looked up the part number online and found it for like $13 elsewhere. This is just molded plastic and I saw the same head going for upwards of $100 on different sites. Be sure to shop around for the best deal and more importantly get the correct size. If you're using 3" schedule 40 pipe keep in mind it has a 3.5" outside diameter so you need a head that fits it.

Some heads come with a "pre-filter" while others do not. The prefilter basically keep large chunks of shit from getting into the tube. You can stretch panty hose over the head. I wanted something a little more weather resistant and really I don't think I need the filtering characteristics of panties for the head so I went with stainless steel washing machine drainpipe filters:













Some shots with everything painted and finalized:











The pipe is huge but really I have not noticed it there when driving:



OK, now for the goodies under the hood...

I was lazy and decided to use this K&N RC-5052AB Universal Cold Air Intake System instead of making my own filter contraption. From what I saw online it would not have been possible to make a filter assembly that would have maintained a large diameter air passage through the filter. For example, I saw a lot of DIY'ers using cone filters but having to mount them onto 2" pipe etc inside a housing. This K&N Apollo filter and housing can be modified to allow 3.5" diameter all the way through. In stock form the inlet has a 4" opening and a 2.5" exit:



It comes with attachments and whatnot for using smaller hose etc. I wasn't using any of that crap since I wanted to connect a 4" hose to one side and a 3.5" pipe fitting to the other. The one side minus attachments is 4" already but the other outlet end needed some work:

















Toilet flange to the rescue:





I cut the center of the Apollo outlet flange out and made it slip over my toilet flange:







I turned a 2.5" outlet pipe into a 3" outlet pipe:



Cleaning up the flange a bit to make it nice and flat, smooth, flush etc.:





I then drilled the matching holes for the Apollo housing:









Sealing it up:



Reassembled with the toilet flange, new longer hardware and painted flat black:





Installation...

Things are tight in the engine compartment so I needed a much more flexible yet sturdy and waterproof hose. McMaster-Carr:

hose 2.JPG


The plan was to slip a hose over the backside of the toilet flange on the fender and route it to the 4" inlet on the Apollo filter. The toilet flange in the fender had a 3.5" O.D. pipe and the I.D. of the hose is 4". I wanted a watertight fitting so I cut the center out of a 3" rubber pipe end plug and slipped it over the pipe:



That allowed me to mate the two and have a nice watertight seal:



Rubber sleeve slipped onto the pipe and you can see that I had to trim the cover over the blower motor a bit to get the hose on:









Dipped down so I could install a new coolant bottle:



The stock rubber gasket on the MAF allows a pipe fitting to slip in. The O.D. of the fitting is 3.5".















I'm gonna add a heat shield around the hose where it comes near the AC orifice tube:



New coolant bottle, Dorman 603-001 Coolant Reservoir Bottle. I'm still not sure this bottle has a large enough capacity! But here it is installed (no room to get a drill in there):











SO....end results...



Not too happy yet...

The engine does not like the snorkel AT ALL. :banghead: :screaming:

With just Apollo filter and snorkel hose left off:



With the snorkel hose attached to the Apollo filter:



The engine is seriously choked out and starved for air. I have 3" I.D. from the snorkel head to the fender, 4" hose from the inside of the fender to the Apollo and 3" I.D. coming out of the Apollo to the roughly 3" I.D. MAF. There are no bottlenecks or restrictions aside from the bends in the pipe and hose. Those could cause turbulence and eddy currents and act as flow restrictions.

The snorkel adds a more throaty sound to the engine:



With no load on the engine the snorkel wants to stall the engine when you goose the pedal for WOT. Under load (driving) the effect is not nearly as bad. I notice a bit of a stutter sometimes and perhaps a slow acceleration at other times. Worse problem though is that the MAF is NOT happy:





I have only had this hooked up for a few hours so I have not even begun to troubleshoot the issues. It could be turbulence from the 90deg elbow right at the MAF causing the MIL to trip. I have a new MAF coming today that I can mess with (removing the screen etc.). I drove to work today with everything connected and it drives fine. Just the MIL light came on several times. Gotta do some experimenting I guess. Dammit.

But it looks and sounds cool! :shrug:
 

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I'd try pulling the top of the snorkel off first and see if you are getting too much restriction from the screening you added. If that doesn't do it, then I'd pull the air filter element out and just run straight ducting to the top of the snorkel assembly. If neither of those net you a performance gain, then you are getting too much turbulence from the ribbing of the flexible tubing, however, I don't think that's going to give you the fits your van is experiencing as much as something else restricting airflow. Possibly, it could just be the sum of the parts that's causing the trouble, but what have other people used for ducting for their systems?

I'd say that if you are truly having problems with airflow due to the flexible ducting, you might just have to look into fabricating your own ridged duct out of fiberglass.
 

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I just installed a new MAF without a screen. I doubt that will have any effect whatsoever but it is what I want to ultimately use and figured it should be in place before I experiment. The screen and filter are a good place to start for sure since those are the only two restrictions. The hose is smooth inside. The hose outside the engine compartment is 100% smooth bore and the hose inside is also very smooth though ribbed somewhat. I dont know what others have used but I have seen many a collapsed hose on the net since I have been looking today. I know mines keeping shape.

Sent from my tachyonic antitelephone
 

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A flex hose doesn't flow the same as a rigid pipe.

I'd start there.
 

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thegreenmachine said:
A flex hose doesn't flow the same as a rigid pipe.

I'd start there.
All the ridges in my hose probably add up to less turbulence than the one pictured here:



Like I said, the hose outside the engine compartment is not ribbed inside. It's perfectly smooth inside and is rigid. Consider it a solid pipe. Hard to see really but the inside is smooth and flat:



The internal hose is flexible and has a thick wire spiral wrapped into the material. It's also rigid enough to prevent collapse and the inside is also pretty damn smooth:





Those ridges are not as deep as they appear, there is clear plastic on them over the wire.

The K&N filter came with this shit that extends to like 4ft:







If that crap wouldn't cause any issues then I suspect my hose wouldn't either.
 

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There are cases to made where it can be very difficult to improve on factory design... :shrug:

As for your issues, it seems like you have created a reduction in air flow from the K&N filter and the double layer mesh thing which is causing too much restriction.

One problem is with having the additional restriction at the end of the snorkel (farther away from throttle body) is that it becomes even more difficult to breathe and maintain airflow. Velocity would be better (higher?) closer to throttle body so restriction near there (stock airbox/filter/MAF location) does not have as much of an impact on airflow. Putting a restriction way out there at the end of the snorkel after that additional long run of tubing is only going making the situation worse.

As for the P0101 code being set, that is from MAF/PCM being stumped due to lack of airflow/low minimum air rate, most likely. I'd look at ways to minimize the length of tubing as much as possible too.

If you feel the need for a pre-filter, maybe a sock style would be a better option: http://www.ebay.com/itm/Small-Droop...Parts_Accessories&hash=item2ed33282d6&vxp=mtr

I'd be hesitant to run much if any oil on the sock as it seems like foam filters (and gauze style) always tend be over-oiled which will hamper performance.
 

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Wow!

This stuff is way above my pay grade, but I really appreciated and enjoyed the McGyvering, creativity, craftsmanship, and documentation on cargocrawler's snorkel mod. :clap:
And laughed at the Corona product placement. :lol:

And great video from jclocatelli, thanks for sharing.
Lisa
 

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Too bad you folks can't just come and have a look. The hoses are smooth inside, the mesh is pretty damn ....meshy too. I wear the stainless mesh when I do hold-ups because it breathes way better than the panties I swiped from the neighbors laundry.

The external piping couldn't get any shorter....not much point in that anyway. The hose inside could maybe become a foot shorter if it didn't route below the coolant bottle. I need the coolant bottle and that dip in the hose is my water trap.

I drove to the gas station last night with the meshless MAF on and it seemed better. I'm going to be recording all my engine data for analysis. That DASHDAQ-XL pictured above can log all the data the PCM monitors. I suppose I might need to put the stock air cleaner back on and record that info for comparison too.

The engine only seems choked in idle right after start-up. External ambient temp doesn't seem to have any effect, it does it early morning and afternoon. It will be nice to look at some numbers to see what's going on. I'd love to see intake air temp and pressure numbers as well as engine load and rpm data between the two systems.

Of course I will be removing and reworking every part of this snorkel system to find the issue. I spent way too much time and money to just live with decreased performance or remove it altogether. Of course I will be documenting all of it here, failures and successes as usual. I posted the info even with the EPIC FAIL because I do want feedback and pointers. Most of the "solutions" are obvious, but in fact fluid mechanics is quite hard to predict when you can't see what's going on inside the pipes. Every nook and cranny in there has an effect. I don't think you can just add 8ft of pipe to any air breathing system and expect things to improve.

I'd love to see what jlocatelli's got under the hood...
 

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I've been to your neighborhood. The girls there don't wear undies.

Have you driven it far/long enough to allow the confuser to re-learn the new air supply?

The air gets "rammed" in at the origin, then has to reverse directions and flow down the vertical diagonal pipe, then gradually reverse directions again to get into the intake. I don't know enough about fluid dynamics to say if that's a problem or not. I know the Toyo's and similar mini-4x4s have the same setup but smaller pipes. But they might be operating at an extreme air starve mode at the expense of looks.

Lump
 

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Lumpy said:
I've been to your neighborhood. The girls there don't wear undies.

Have you driven it far/long enough to allow the confuser to re-learn the new air supply?

Lump
:D True that. My neighbor is an anomaly though...25 year old Chemical Engineer. She wears granny panties. :x

I have only driven the van maybe 30 miles with the snork before the new MAF went in yesterday. Someone died on the 101 in Hollyweird today so I ditched work knowing I'd be a few hours late anyway. Tomorrow I will drive with the new MAF. I can also go in there and reset all the 'learnin curves manually. Really I aint done shit yet as far as troubleshooting. I'm lazy. I'm also a bit pissed because I expected it to just work and I have a buttload of other projects to get crakin' on.

Hey Silverbullet...

Why did your buddy ditch the snorkel on his overland race rig? The before pix have it but the race pix don't.
 

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97cargocrawler said:
Most of the "solutions" are obvious, but in fact fluid mechanics is quite hard to predict when you can't see what's going on inside the pipes. Every nook and cranny in there has an effect. I don't think you can just add 8ft of pipe to any air breathing system and expect things to improve.
Captain Obvious to the rescue? :roll: :lol:

That is precisely why it can be very difficult to improve on a factory setup. :violin: I do hope you get your setup to work at least as well as stock though. :thumbup:
 

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97cargocrawler said:
Hey Silverbullet...

Why did your buddy ditch the snorkel on his overland race rig? The before pix have it but the race pix don't.
I will have to ask, but I assume, as that it is not a asset needed for the Ultimate Adventure. I am sure it will be reinstalled now that the adventure is over.

Posted By Scott Bruder on 08 Jul 2014 06:46 PM
It interfered with roll cage. We may try to put it on now but the air intake is 60" off the ground right now. not sure i need it anymore!
 

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Those Subaru posts:

An entire page of posts and ONE question about performance and MPG. Answered by "I haven't got the chance to check yet".

The fluorescent pink PVC elbow in that one station wagon is too cool for school.

And the Toyota Corolla with ski racks, snorkel, tach, off road lights.



Lump
 

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Hey, those Sachs MadAsses are pretty cool scooters, this is what I prefer to rip around town though - Aprilia SR50 Ditech :auto-dirtbike:

Even modified air intake with trumpet to pull cool air and adjustable fuel pressure regulator...
 
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