That's why I people should drill a hole in the bottom of the elbow like with the snorkusOriginally Posted by Sinister
This is a discussion on "The BIG BOV thread" (Where all bov question threads get merged) within the Engine Modifications forums, part of the Tech & Modifying & General Repairs category; Originally Posted by Sinister Did you notice there was stuff in the bottom of your snorkus? Well now all of ...
I'll bet my best friend's dog on it. It costs 4 hours, $100, and will make real horsepower. It won't mess up your MAF sensor ever, at all, doesn't even get damp in a rainstorm, reduces turbo lag, knocks 4 pounds off the car (perfect for those with an Optima RedTop, 4lb lighter than OEM batt.). This mod implies a panel filter upgrade.
There's a lot of other less important reasons why this is the way to go. There's no funky, hard to find cleaner for most panel filters. The ports I drilled in my airbox are tuned. I will explain that in a minute.
It gives the car a mean turbine spool sound, louder than the normal rumble of the boxer block when warm. Very much louder in fact.
I want to mention that it doesn't aggravate Police officers who might be interested in what is under the hood. They know to look for CAI tubing and cold air cones, and they will send you for a State Inspection here where I live... and it will fail just to get them the bucks. This looks like factory parts, and will outflow almost any CAI, so just read on...
I will happily send you all to Staples for Desk Wire Hole Grommets (2 of the 3" ones, one 2", so you can do the same thing. You will also want an Apex'i Aluminum mandrel bent elbow (about $12), a Weapon-R silicone hose coupling (about $7), a cheap coffee cup from WalMart (travel cup, the black ABS ones that go for a dollar in the automotive dept.), a hot glue gun and high-temp hot glue (Walmart, $12), and a Subaru WRX/STi. Since Staples doesn't have all this stuff (and why not?!), you will do a little driving around in your 'rich condition with a CAI you spent $200 on', ignoring the CEL from misaliagned MAF sensors, or whatever else included you in this thread-to-be.
Once armed with the car and it's new pieces and parts, get the airbox out, whether it is out of the box in the garage, or out of the car, and get the sharpest, cleanest box cutter you can find, and carefully score a fine circle around each grommet until you have mapped out the holes completely. Go where you can easily clean chards of plastic after cutting the holes. Use the box cutter, and go very slowly, making single clean passes until you have effectively drilled through it's walls.
Throw away the pieces of plastic left over, and get the grommets out of their packaging, and pop the dust covers out of them. Look! Port tube flares for $3! They are ABS, solidly dyed, and will take a sanding like a champ. Same for the coffee cup, cut it so that the rim is all you have left, and use it's ridge to seat it in it's hole. Get your hot glue gun really wicked hot...
Once you are at the point of having to respect just how hot your hot glue gun is, make a bead for one port at a time, and seal it into place. Pics should outline what you are doing, they are not the rule. The reason you want really HOT hot glue is so that it doesn't turn into that globby mess that looks like it was made in a pre-school class. When at it's hottest, it is a true liquid, and will seal a fine gap very quickly, while offering it's adhesion characteristics at maximum. This builds a strong weld which will never fail.
After this setup is fabricated, the elbow is a piece of cake. As long as the rubber (floppy piece) grommet that was part of the snorkus joint is still attached to the airbox, the elbow can be clamped in from the inside. I glued that just to ensure a tight seal and no wiggling. Also, make sure you align the elbow to allow the airbox to be removeable for future work. It should point slightly toward the front headlight, which will create a ram effect from air through the lower dams. It is very effective, I am using it, it works.
When you get it into the car, you will see that the grommets are not the most aerodynamic pieces in the environment they allow passage to. It is wise to trim them until they are either vaned for turbulence, or shaved flush with the inside walls.
I chose the vanes, since they require more work, and are slightly more effective. Both will be nearly equally intense a difference in power and sound, but the vanes just seem to lend a smoothness to it all. Could be the placebo effect... at any rate, check the pics for a guideline, and you can see where I am with it. I used a Weapon-R SRI for about the last 4 months, and it isn't really very much of an upgrade, just loud and very moisture absorbant. It came with a ton of extras for free, and I figured I could get power out of it with a tune, but it is more restrictive that this airbox after the mods.
In the pics, I have not yet cut vanes to match the movement of air, but the install pics of the box in the car will show that very clearly (to be posted when it isn't freezing cold outside). I am sure you can see how to do it just by looking in the airbox, which is already a vein-grid to stagnate cooler air and allow it's induction when called for. You will increase this effect to it's maximum by shaping the sides of the port holes' tube ends to match the veins in the airbox. This allows the turbulence from the ports to compliment one another, rather than cancellation, which can result in a lean/rich ecu malfunction and a CEL. It can also cause detonation and stalling... none of which are a risk if my formula for port diameter and overall location is used. Port length is not so much an issue as covalence. It is better to just terminate them as early as you can (smoothing them to the walls completely) if you are in doubt of your own work at all.
If you run into trouble getting parts, or getting started, go for it with the questions!
pretty clever. did you come up with that yourself, or did you c & p from somewhere else?
"I do well to be angry, even unto death."
I ♥ rice
1)I don't think you quite understand how ram air really works........
2)Unless all holes are pulling air from the fender well you have sucessfully turned the factory CAI into a hot air one.
Better idea with less work:
The velocity stack is installed through the fender side.But we digress as we are now way off topic from BOV's.............
So, yep, I am the only one I know who has this done, but it ought to be readily available info IMO. And... Thanks for the compliment>
I don't know if you are aware of the fact that our intake tract pulls air from a really dirty source, and also that a turbo doesn't care how cold the air is, it cares how much. I have lower engine temps with this setup than with the shortram. Good enough for me.
"Bro ima get Bimota BB3 because expert. My parents have 911 turbo but awd won't let me launch, ima get 962 twin turbo Group C bro." -- SD_GR
Grandfather of the Bugeye Mafia
2013 Subaru BRZ Limited
2002 Subaru WRX Bugeyebrid Wagon -- SOLD
2002 Subaru WRX Sedan -- SOLD
I understand, and am well aware of "tuning the ports" to make a SPEAKER "think" it's in a bigger enclosure than it really is, or to "tune" for a certain frequency response; I used to do high-end automotive audio/video for a living. What I do not understand, is that with all the various ports in your airbox, how it doesn't pull in hot air from the engine bay, and/or the friggin uppipe thats about 12" away, and HAF?
do you have actual DATA to back up what you say, about this "making" power, and the differences in engine temps?
I'm skeptical, I'm not saying it isn't possible. Not that I care either way, at this point, more so that others don't get falsified information.. And I'll be ripping this out of this thread tonight, and putting it where it belongs, not in the BOV thread
'96 Dodge 2500 CTD @ 40psi - over 700 lb/ft TQ, 7" stack, and 5speed! - SOLD
'01 Dodge 2500 CTD 6-holed hand-shaker - 3850# dual disk - 900 lb/ft - SOLD
'97 Dodge 3500 CTD DUALLY built Auto - 40psi boosties - 750 lb/ft - SOLD
'01 Dodge 2500 CTD Slobbermatic -
'14 VW CC R-Line 2.0T 6-holed gearbox - 4100mi on it in 2.5yrs...
As already said,cold air is denser.Not to metion the IAT sensor is in the MAF.You have one source pulling from the fender well and the other 3 from the engine bay.How much?Show me an intake CFM flow calculation for the stock turbo and the engine.I guarantee one hole can supply more than enough air.The problem here is you don't seem to know alot about the mechanical aspects or engines and turbos.Especially since your using a car audio program to determine airflow for an engines airbox.This where the people all hell bent on intakes loose sight.Cutting a whole bunch of holes into your airbox doesn't help unless you are freeing up a restriction.If my car requires 300cfm of air and the airbox is capable of supplying 350cfm of air and I install an air intake or mod my airbox to flow 600cfm do I gain anything?NO,because there was no restriction present in the first place.Plus the MAF housing is 65mm and the turbo inlet is around 60 mm.Increasing the airbox inlet hole to 70-75mm will supply more than enough air.I applade you for trying something new and I am just giving constructive criticism from a mechanical/scientific stand point.Originally Posted by Impreza2.0
Last edited by Donkey; 04-13-2009 at 02:26 PM.
OK, I totally get you about my intake making mad bass. I laughed really hard at that actually... The idea was to make the tuned length as acoustically inefficient as possible, thereby passing the most air per determined length of specific diameter tubing. There really is no magic to it, there are a few "no-no" lengths, but it is really actually a pretty free system, limited primarily by engine bay dimensions. You could guess, or buy an eBay short-ram and MAF adapter, and still get a decent tune out of it. If you are unlucky, and don't know what is going on, and you put a gap in one of the two couplings, lengthening the tube to some point where you bang the MAF with a non-linear air flow, it will wonk your car out.
The airbox I milled the heck out of is rediculous and I know it. The bellmouth velocity stack IS more intelligent, I just wanted to Swiss cheese it until there was as little left as would still work well. It does. I don't really recommend it, and there won't be a how to...
I appreciate the sense of humor, and the doubt is deserved. I use a Weapon-R short-ram, the v-2 filter, just because I can clean it 5 or 6 times before the foam is trash, and a new foam pod is $20, less than the K&N cleaning kit.
In my upcoming post in this thread I have a BOV related question, as a noob to the idea, and I would love the candor found to my 'invention post', which I really think makes more sense if found in Engine Modifications since it doesn't relate to turbo tech too directly, but hey...
It doesn't resonate at all, because the couple of points that do exist were avoided. Basically it comes down to avoiding the idiocy of the untuned short-ram, where the filter is that aweful distance from the MAF, where turbulence destroys the reading at certain RPMs, wrecking up A/F ratio, and making your car wonk out when you want a crispy take-off.
So far I have a ported TD05, turbo-back exhaust, excepting the Borla Hush muffler, the rest is all Apex'i w/bellmouth downpipe, stage 2 tune, Weapon-R short "V2" intake, and I have a Greddy Type RS blow-off valve sitting in a box. I am really geared to install it, but I have a couple of questions. I bought this car the way it is, all but the intake, which was part of the ECU tune, and had to be completely OEM to be allowed to sell on the sales floor. It ran like a garbage can until the intake was changed to the WR model, proving the ECU was way beyond factory tuned. I want to know if there is a downside to replacing the OEM bypass valve with a tuneable billet model? It is Greddy, and I understand them to be reputable and patient craftspeople, and that the quality of the product is not a concern, but that installation be done patiently and with care. The piece is attractive, but how useful is it? I hear the "loss of boost" nightmare constantly, and I know it isn't going to sound any different. It isn't a cool sound I am after. It is the option of using stage 3 maps that I want. The TD05 is externally wastegated, with something that is about as nice looking as the stock BPV, and I wouldn't mind replacing that either... I just wonder how much harm it could possibly do to use a finely machined billet unit vs. the cheap stamped steel one that is being mounted at the factory?
I have been told that the boost being manufactured in the turbo is not going to be allowed to be used because of a code in the ECU telling the turbo to go to "limp mode" for a few seconds. It results in unbelievable lag. Will the billet unit respond faster due to weight?
I'm not a big fan of Weapon-R's filters.I have used on a while back on a different vehicle and I had horrible UOA's with it when I sent oil samples to Blackstone Labs.They filter very poorly.AEM Dryflow or Amsoil Nano filter is the best ones out there in my opinion.No oil and completely washable.Originally Posted by Impreza2.0You actually want the filter far away from the MAF.Most pod filters have turbulance problems because the MAF is to close to the filter.Short rams generally have some piping between the MAF and filter which help kill some of the turbulance.Originally Posted by Impreza2.0
I get you about the foam being bad, and it is, they are just sooo cheap. I might try an AEM on my next change. Thanks for the suggestion. As for the aftermarket MAF adapters you are showing me, I can guess (please correct me if I am wrong) that those require a retune. If you write to those manufacturers, and ask why the tubing is not an inch shorter, they'll tell you the same. I was able to bolt the WR intake on and go, no tuning required (might be smart to do anyway). The piping is nice, the couplings are good quality, but yeah, I agree wholeheartedly about the filters. Cleaning them works the first few times, but being foam, they turn to trash quickly. I will also guess that you have a completely rebuilt engine, and that you have major modifications, and that a little upgrade like an intake is peanuts to you, and you have been through it all with them.
I am really done with my intake, it works perfectly. I can see how the air charge may be a bit hotter at idle, but on the road, that is a cool spot in the engine compartment.
I am really interested in an answer to my question about aftermarket recirc. BPV. How can it not improve response during shifts? A lightweight precision CNC machined piston has to be faster than a stamped steel one... Adjustability seems wise too, if other upgrades are made more easily tuned-for.
Last edited by Impreza2.0; 05-03-2009 at 07:17 AM. Reason: hmmm...
I have no idea what your talking about here,you didn't make any sense.Maybe you can rephrase your question?What exactly makes it go into limp mode(you didn't state)?The only time you should get a "code" associated with boost is when you hit the boost cut.This has nothing to do with BOV/BPV's.Not sure why you think the weight of the BOV has anything to do with its performance but I guarantee the stock cast aluminium BPV is going to be lighter than any billet aftermarket unit.Originally Posted by Impreza2.0
Last edited by Donkey; 05-03-2009 at 07:33 AM.
It seems boost cut is initiated early. I don't want to know how to tune the BPV, I want to know if replacing it with a nicely machined one is going to make any difference in reaction time during shifts. It's a bypass valve, not a blow-off valve, I do know better, and no: until I have deeper understanding of the systems, and have the mods that require it, I will avoid the BOV.
I just wonder if a fully recirc BPV is a good upgrade, the one in question is a Greddy RS.