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DIY snorkle

21K views 89 replies 18 participants last post by  AstroWill 
#1 ·
Anyone have any pictures or the know how to do a snorkle?

It doesnt seem like theres to much room to work with if you ran a pipe straight out of the top of the engine if you were to take out the existing airfilter and box...
 
#79 ·
I have way more information than I know what to do with. I have tried graphing some of the important bits but it all looks too complicated. Really when it comes down to it all we care about is whether or not the average engine performance for any given excursion is improved, the same or degraded by the addition of the snorkel. Obviously no matter the situation we know having cooler, cleaner air is beneficial for an engine no matter what the circumstances. Most snorkels are attached all the time since nobody wants to fuss with it before each outing. Ideally we want the snorkel to at least match the performance of the OEM intake equipment so we can leave it attached and never think about it again. Not all snorkels are created equally, but mine seems to at least equal OEM equipment and surpasses it as far as maximum intake air temperature (IAT).

As stated previously I ran three individual tests under similar conditions. I did not use the AC and the windows were up the whole time. Each time I followed the same route, observed the same speeds for each leg of the route and each trip took about 24minutes. The first test was with the snorkel and K&N filter in place. The second test was with the snorkel detached and the K&N filter configured to intake air from the front grille. The third test was with the OEM airbox in place.

Click the chart to read it easier:

COMPARISON DATA 1.JPG


Basically the chart shows that having the snorkel in place is not making a bit of difference. It is neither harming nor improving performance to any large degree. The only major difference is that the maximum air temp that was allowed to enter the engine was 16*F lower with the snorkel as opposed to the OEM airbox. So lets say that was sitting in traffic at a stop light...the air was 16* cooler entering the engine. That's good news.

You can also see from the MAP (manifold absolute pressure) numbers that the snorkel is not acting like any sort of "ram air" device. The pressures are pretty much the same inside the intake with the snorkel as without. You can also verify this by looking at the volume of air passing by the MAF (mass air flow) sensor. Those numbers are also pretty much the same.

I tried to display data in a simple way. I'm not bothering with the maps of my route with the GPS data, 3D graphs of measured data or any other type of number crunching, confusing analysis. My goal was not to show you folks that the snorkel is creating some huge improvement in performance but rather to show myself that having the snorkel in place is not robbing me of any engine performance. I know the benefits of having it and the situations that require it are far and few between. Basically it just looks cool on my van. Just like my 35" tires there is very little benefit to having them aside from the rare occurrence where I require more ground clearance. The situation where I require a snorkel is also rare.

On the table you can see that max HP was less with the snorkel as opposed to the OEM airbox. Keep in mind this measured value is the max HP used during the route. Cruising measures zero HP. Acceleration measures positive HP. Deceleration measures negative HP. I can't say that with the snorkel I used less HP to maintain the same speeds because it is possible that I also braked more (more negative HP) during the other two tests. The results for HP are too close to make any conclusions with. Typically performance gains from aftermarket products are displayed in graphs showing HP vs RPM and how you get more HP at any given RPM when the product is beneficial to the engine. Perhaps I could get better data for something like that by doing a 1/4 mile run as opposed to a 25minute excursion through various terrain. I'm not racing my van short distances so for me averaged values for an entire excursion are more useful.

If you would like to know any specifics about the data please ask.
 
#80 ·
97cargocrawler said:
Basically the chart shows that having the snorkel in place is not making a bit of difference. It is neither harming nor improving performance to any large degree. The only major difference is that the maximum air temp that was allowed to enter the engine was 16*F lower with the snorkel as opposed to the OEM airbox...

...Basically it just looks cool on my van...
...The situation where I require a snorkel is also rare.
I'd say you beat the probabilities.

Common sense suggests that ANY increased length of pipe on the intake would DECREASE air volume/velocity. Think about all those guys that inverted the lid to their air cleaner in the 60s.

I'd venture to say that in 100% of civilian (non military) applications, the snorkel is for "just looks cool on my van [jeep/subaru/moped whatever]". With your OEM intake, I think you'd have to be in about four feet of water to begin worrying about sucking DiHydrogen Oxide into your intake.

So throwing the "Need it for stream crossings" thing out of the picture you, in your application, end up with -
- Looks cool
- Delivers cooler air

I'd say you're one up on the lesser engineered, less well-thought-out snorkels that run vacuum cleaner hose up to the roof.

We could, of course, ask the question "Is 16* cooler air positive? Negative? Null?".

We also could consider the "hassle factor". Your snorkel is probably not in smog compliance in CA. So whatever that presents in terms of inspection, CHP, APCD (do they still have that?) etc, may be worth factoring in vs the two demonstrated points, looks and cooler air.

I'd like to see the GPS data. Comparing the engine data to the vehicle speed might be telling. I have to think that there's at least SOME amount of ram air effect happening.

Lump
 
#82 ·
FASCINATING ...
ABSOLUTELY FASCINATING to see the "scientific approach" blended with "seat of the pants" engineering.

I do some thing similar with my retirement "career" designing firearms parts and accessories fir M14.CA.

First there is an "idea" or concept. Then we brainstorm the idea on napkin drawings, followed by SW drawings on the computer taht can be prted over durectly to the CNC machine. Then we create a working prototype for real worl testing. Then we repeat and refine till we get a finished prototype we like.
Then we post the prototype on a web site forum for "crowd sourced" feedback.

Nice to see some one else using the same processing.
 
#83 ·
I may have loosely employed the scientific method but my tests have far too many uncontrolled variables to be scientific. :mrgreen: My DASHDAQ-XL is made by DREW TECHNOLOGIES which is an OEM supplier of data acquisition and programming devices for the auto industry so I am somewhat confident in the accuracy of the device. If there are any errors in the data it was carried over for each test so it should factor out being that I'm just looking at raw data for difference in value comparisons and not concerned with the values themselves. Just looking at two apples to see which is bigger but I could care less that they are apples. I did notice that the GPS has me down as going about 62mph when the DASHDAQ had me at 65. That error could be in either device or most likely the vans ECU since I programmed it. My tires are a bit shorter now due to wear so the speed calculations in the ECU must be off. I probably have 34.5" tires now. Anyway, there are errors for sure but each test would have the same errors.

Here is the GPS data. DO NOT use it to show up on my doorstep. I don't appreciate unannounced visitors :violence-guntoting:

View attachment INTAKE MODS MAPPED AREA DATA.txt

View attachment INTAKE MODS MAPPED AREA DATA.xlsx

That list is continuous and has all three tests in order. There are about 600 lines of GPS data per test.

Here is the route:

intake mods test mapping area.JPG


Basically I start in the middle and go down a very steep freeway, get off and come back up. Then I do the right side of the Y which takes me partially up into the Angeles National Forrest which is a really steep grade. Then I come back down, get back on the freeway and do the left side of the Y which is flat highway that ends in a very steep grade. I get off and come back down the grade, exit the freeway and do a few miles of flat city streets. All the highway driving is at roughly 65mph. Angeles National Forrest leg is 45mph and city streets is 35mph.

ASTROSAFARI.COM will not permit my log files with .dif file extensions to be uploaded. If you are interested in those files for analysis in LogWorks3 or some other tuner utility let me know and I can email them. You can see the basic data in the .csv files though using a spreadsheet program or notepad:

Snorkel data:

View attachment snorkel.csv

K&N filter with hose routed to grille:

View attachment KN filter only.csv

OEM airbox:

View attachment OEM airbox.csv

I'm not hiding any data, feel free to analyze it and draw your own conclusions, disprove my finding etc. I'm certain someone could look at that data and figure out all sorts of cool stuff. I'm not an automotive engineer or a tuner.

In future tests I will record things like fuel economy. I wasn't able to do it this time because I can only record so many data channels at once with the DASHDAQ. I'm also interested in fuel bank data (rich/lean etc). Also, I should note that I have not experienced any more MIL (SES, check engine light) codes since I replaced the MAF sensor. My guess is that my old MAF sensor was worn. No codes thrown with the new MAF for any of the tests or my daily driving for the past week. Idle on start-up with the snorkel is still a bit rougher than I'd like but after a minute everything is chill.

I will continue to ponder new ways of displaying the data. Its difficult because there is so much and each test is not the exact same length of time and don't start at exactly the same spot on the pavement. I can't just overlay the data on a graph very easily but I will see what I can do.
 
#84 ·
OK. I'm not able to draw any kind of conclusions from the geo data either. I'm not even able to read it in GE so I'm just looking at text. I was thinking maybe we'd see something like MAF=20 @ MPH 0, then MAF=100 @ MPH 65.

I do have a question about the earlier posted chart of engine data that compares OEM vs KN vs Snorkel. Where the RIGHT column reads "SIMILAR DATA" is that your own interpretation or the software's? I note that the snorkel takes a 31 hp hit over OEM and a 24 ft/lb hit over OEM.

So far it looks like the KN filter wins. If that is indeed the case, how about PASSIVELY feeding the snorkel air to the KN. ie, don't make a hard connection under the hood but let the proximal end of the snorkel duct simply BLOW it's cleaner, cooler air onto the KN filter. Perhaps that tends to achieve the best of both worlds. Slightly cooler air (not as cool as the sealed snork) but 31 hp more, 24 ft/lb more, likely better MPG etc.

Lump
 
#85 ·
Where it says "SIMILAR VALUES" that's my interpretation. That whole chart is made by me using data that I gathered and the LogWorks3 software compiled. The LogWorks tables and charts are far more complicated to read but I can take measurements on the charts and take snapshots of the screen for you to see. Choose a leg on the route and I can do that.

The HP data is confusing at best. As you can see the average over the three tests is similar. That means that the power added and subtracted from the wheels was similar in all tests. In other words I accelerated and braked about the same amount in each test. The higher HP you see for the OEM intake means that it required more engine power to climb the same hill etc. than the snorkeled intake did. In other words the engine worked HARDER with the OEM intake on whatever obstacle the van encountered. That max number is a single data point. It could be an outlier. I will have to look at my graphs and see where the max data point for each test was encountered on the route. If they all happened in the same place then I could say yeah the snorkel kicked *** on that hill etc. I will have to look.

The HP data required me to enter a vehicle weight for calculations. I GUESSED at the weight of my van by adding 1,000lbs over the 5600GVWR listed on the door sill. So my weight for the calculations is 6600lbs. I have no idea what my van actually weighs. But like I said, comparing apples to apples but I could care less if it's an apple or a pumpkin.

Over the next tank of gas, about a week, I will run the OEM intake and measure my fuel economy. The following week I will put the snorkel on and do the same. I don't want to loose a few mpg's. I can always leave the snorkel on, disconnected and use it whenever I need it. I like how it looks so I don't think I will be removing it from the van if the mpg's drop, just leave it disconnected and use the K&N with a shorter tube. Normally I could give a shit about mpg's as long as the mod gives me some huge advantage in some other respect. Like my huge tires allow me to flatten idiots in Prii and scooters and the debris just flings right out of the tread, self cleaning. Or my rack that weighs a ton but comes in extremely handy when Lump needs to make a landing in his helo.

EDIT: Lump you can see the data you wanted in the Excel files labled Snorkel.csv and the others. HP at this speed etc. but like I said the HP is only positive if the wheels are under acceleration...not coasting or brake applied.
 
#86 ·
97cargocrawler said:
I GUESSED at the weight of my van by adding 1,000lbs over the 5600GVWR listed on the door sill. So my weight for the calculations is 6600lbs. I have no idea what my van actually weighs. But like I said, comparing apples to apples but I could care less if it's an apple or a pumpkin.
You should definitely get that sucker on the scale!

97cargocrawler said:
Normally I could give a **** about mpg's as long as the mod gives me some huge advantage in some other respect. Like my huge tires allow me to flatten idiots in Prii and scooters and the debris just flings right out of the tread, self cleaning.
It's a good thing my scooter can out accelerate (just!) your van or else I'd have to lay low and pass underneath! :auto-biker:

Helo visual:
 
#87 ·
BTW, LOTS more data to follow in the next few weeks. Fuel economy as mentioned but also extreme traffic data. I spend a lot of time sitting in the worse traffic Los Angeles has to offer along with bursts of speed for short distances and hard braking. The stuff that destroys your engine. The tests above, while mostly representative of my daily commute are during a saturday afternoon when traffic was free flowing. I didn't stop for more than a minute or so during any leg of the route. That is VERY unlike my daily commute. I already know from previous monitoring that the snorkel provides vastly cooler air to the engine while sitting in traffic despite the summer temps here in LA. The snorkel then is sucking in air that's much cooler than the air under the hood for several minutes at a time. I suspect I may see some data in the near future that shows the snorkel is better than it looks so far. Hopefully I can find a better way to present it as well.
 
#88 ·
You certainly do get a ton of data from the DASHDAQ-XL! :thumbup:

Isn't it (kind of) funny that the worry with MAF codes, etc after all that work building the thing turns out most likely to be a worn/bad old MAF? Always seems to work like that and if you didn't have a new one on hand to swap, definitely could have been chasing all sorts of things.

The snorkel performance looks decent overall. As for rough idle at startup with snorkel, I wonder if that isn't just the PCM still learning? It's almost like after I re-program with the JET programmer and idle is always funky for a bit.

Looking forward to what else you come up with for fuel economy, fuel trims and maybe even high heat soak condition like sitting in traffic for extended periods. You'll sweat out at least 10-15 lbs! :D
 
#89 ·
Oh, huh. It's been about 6 months now since I last posted about my snorkel. It's still on my van, still in use everyday and I have had no issues with it. I have driven in pouring rain with the scoop facing forward and it was no worry. If any rain got into the tube I'm sure the trap I created in the hose held it long enough for the engine temps to evaporate it and pass it into the engine. My fuel economy has definitely NOT taken a hit, improvements are hard to judge since I'm always adding more weight to my van. A few times during the summer I got a SES light with a lean code while idling or creeping in traffic on the hottest days. It always occurred at the same spot in my commute so something there created just the right conditions to throw a code. I do enjoy seeing the difference in intake temps versus engine temp on my monitor. The snorkel is definitely the ultimate cold air intake.

I have not forded and rivers yet. I know the tube is liquid tight but nothing else on my van is. I suppose one day I may attempt to waterproof the ignition and extend the axle breather vent, but in reality I think I know the limitations of the vehicle. I'm not so sure it will ever be crossing any waterways. With that said I don't think it's any less useful than the ones I see on FJ Cruisers in the city everyday. I like the look it creates for my van, I like the sound, I think it has created a higher flow of air in conjunction with my new exhaust pipe and it has had no ill effects that I can see on the engine. Is it useful? Probably not, but it's one of those things setting the look of my van apart from yours and that makes me happy.

:driving:
 
#90 ·
97cargocrawler said:
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
Do you have the part number?
 
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