K & N Intake + (Stock) BOV Question

[Muramasa]

From the instructions manual for the K & N typhoon intake, the picture of the stock BOV was opposite of mine. In the picture the BOV is vertical while mine was horizontal. Whenever in my car without the K & N installed, there was no BOV sound until 5-6k RPM. Now with the intake and I switched the position of the BOV from horizontal to vertical, i have sound now at 3k RPM but the weird thing is.. it sounds like a quail using a microphone. Its loud and sound like that kind of bird. I am wondering is that normal and can people post pictures of what their stock bov looks like and if anyone has the K & N how did they set up their bov. Thank you.

[han74j]

yeah theres nothing wrong wiht ur car! after u get the k$n ur car is way louder, it sounds almost like we have a super charger!!! heres a link

http://www.socalevo.net/forums/viewtopic.php?t=1227&highlight=k+n+intake

[evod]

muramasa, put the bov back in the way it was in the stock orientation. K&N screwed up on their instructions...the picture is incorrect. follow han74j's example on the pictures in his link.

[Muramasa]

If I left it in the way I put it instead of horizontal will it kill anything?? My car sounds like a sick quail =P Whenever it boosts and I let go of gas, I get the quail sound =P. Will there be any BOV sound at all if I put it horizontal?? Cause its kind of nice with it vertical. I can just step on gas a little past someone and let go of gas and it blows off with the sick quail scream.

[akara1]

If it is in the wrong way, you could be getting compressor surge which can eventually destroy your turbos bearing. If you put it in how it was originally, you will hear your stock bov with the k&n. One of the shops that worked on my car had put it in backwards, and the car ran like crap. After looking at han74j' pictures, i fixed it and now my car finally runs much better.

Make sure you have it in the right way.

[evod]

muramasa, if u left it in there that way, due to the design of the stock bypass valve, i would think that it wouldn't be responsive enough to open when under boost. when under low boost(normal driving) you may get a small bit of compressor surge...but it should still be able to open. however, under high boost, the vacuum on the diaphram on the manifold side probably won't be enough to open the valve with the force of pressure on the valve itself...keeping it closed as you let off throttle. of course...this is hypothetical as i haven't heard of anyone doing any serious tests with the stock bypass valve and i have no interest in doing it myself =0) if you look at HKS's design however, its just that. but with their larger diaphram, the vacuum side is able to still open the valve under heavy boost loads...that's what they call the "pull type"....where higher boost pressure presses down on the valve itself to help to keep the valve closed. that's also the reason why the HKS one is such a great design(at least the new one...old one was plastic body...sheesh..talk about a big mistake).

[Muramasa]

Ok things are bad now. My car is stalling in neutral. From 3rd gear downgearing to second to make a turn into my work plaza it died halfway thru the turn. Power steering was gone and it was dead dead. I had to slam on the brakes and start the car again. this is the 3rd time it stalled... from the K&Ns picture, it shows the vacuum hose(i think its called that from the bov(smaller tube) it goes over that radiator pipe or something. But to go over it the bottom is pinched. So is that whats causing me to stall?? Someone please tell me what to do?? Han74j... says with it stock set up, he is also experiencing near stalls. One other thing is when I was taking out the mas from the stock airbox i accidently poked the honeycomb. I straighted out the bents as best I could and it seems ok. So i have no idea what to do. I am in ontario and I live in arcadia. Im afraid to drive home and have it stall at 70mph on the freeway on a turn.

[Muramasa]

Ok this is so far what I have found out. After putting the BOV horizontal like stock, the blowoff sound is 3 times quieter and has that hiss blowoff sound. Before if it was vertical it was 3x louder and sounded like a sick quail. So far my idle seems fine now and no more would the rpm dip to 200 (not 2000) on neutral. Yet somehow accelerating in 5th gear to 110 seems a bit slower.. There isnt that power pulling feeling anymore. I wonder what I am missing.

[evod]

muramasa, sounds like you got it right now. the high end ur kinda missing out on may be due to the stock bov having a tendency to leak, or so i've heard from a lot of previous dsm guys. but either, sounds like u got it now =)

[Muramasa]

Ok I have another problem. Before I installed the intake and my oil change being due in about 300 miles, my service light went on. I went to the dealer and they said I was due for the 6k mile service, so i did it. After that happened I installed the intake and its been few days and now its like everyone else says, the bov is horizontal. But now my service light is on again. Could it be that I punctured the honey comb or could it be something else?? The intake and turbo timer is the only thing I have on my car. Please help!

[evod]

muramasa, a punctured or damaged MAS could cause a check engine light. i have the Typhoon currently on my car and i do get a check engine light every once in a while...however it came on after i installed the exhaust, so i can't blame it solely on the filter itself. i've noticed that using different fuel's sort of effect the check engine light... as far as i know tho...there's no way to determine the cause of the check engine light from just observations...you have to get a scanner and pull the code to see why it went of in the first place.

[perversity]

Since you have increased the volume of air getting into the MAF your car may well be running a little rich to compentate, which is why it seems slower at WOT. Also may contribute to the CEL. Something to control the Air/Fuel mixture, like an SAFCII would correct the a/f mixture for you, once properly tuned on a dyno.

[Muramasa]

A SAFCII watever that is is expensive huh? Once i get that I need a bunch of other stuff too huh? Well my service light went off again. Its been on and off 2 times now. Should I still get it checked out??

[evod]

muramasa, the SAFC2 is the APexi SuperAirFlowComputer. it basically allows you to modify the fuel curve of the stock ecu by intercepting the signal from the stock mas and then modifying that signal, and sending the new signal to the ecu. this tricks the ecu into thinking that there are different amounts of air going into the engine, thus the ecu will inject an altered amount of fuel. and like perversity said...its best to tune it either on a dyno, or else street tune with the proper datalog equip. you don't need to get a lot of stuff along with the AFC...but having a few other tidbits(exhaust, dp, etcetc) will allow you to extract more potential through the use of the AFC. keep in mind the AFC is quite limted...as it only alters the airflow signal to the ecu, not injector duty cycle and no control over ignition.

[Coolguy949]

Everyone seems to being putting in their BOV backwards these days. I've worked on DSMs and other turbo cars for over 5 years now and I've never seen a BOV installed without the spring pushing against the boost until now in the evo. If you think about it logically, you'll get a lot of flutter and/or surge if it's on backwards because the way the piston is shaped. It's like an upside down T. Think about if you had the boost pushing down on the T while it's trying to open......flutter. That's why you have the side that the T pushes down on attached to the side the boost is coming from.

[evod]

coolguy, yep...its almost like people have worse short term memory than i do when reinstalling their setups. wasn't this the same issue with a few people installing the forge bov? but yea...either way...except for the hks ssqv....i don't think there is another bov out there that is pull type(with boost pushing up on the T as coolguy was saying would caus fluttering). enjoy guys =)

[TrickedOutEVOVIII]

hey guys...hows the greddy type s with a K&N intake?? compatible or not?? any problems that you guys have heard about??