arggggg i need more help!!

jake15 · Post by **jake15** » Sat Sep 04, 2004 7:15 pm

first off a little about my car, 90 legacy w/ ej22t conversion and awd conversion, with a td05-16g and wrx intercooler with stock wrx bypass valve. and i've had a little trouble getting it to work right, thanks to vrg3 i got my car's check engine light to go off (wrong maf) but now it runs really rich and the bov is always venting air out at idle. now the consensus at the shop is that since the bov is always venting then lots of air must be coming in, and the maf may be dumping in more fuel thinking the engine is at a higher speed because of all the air coming in. but we dont know, so any help is very appreciated. thanks,

jake

mTk · Post by **mTk** » Sat Sep 04, 2004 7:35 pm

How do you have the BOV set up/connected to the intake tract?

MK

jake15 · Post by **jake15** » Sat Sep 04, 2004 8:04 pm

its connected right to the wrx intercooler where it is normally on the wrx, and the little hose that connects to the stock bypass vlave is on it (the one that connects to the intake manifold under the brake booster line)

vrg3 · Post by **vrg3** » Sat Sep 04, 2004 8:50 pm

The stock WRX bypass valve is meant to be open at idle. It's not venting; it's actually sucking air in. Unfiltered and unmetered air.

You should plumb it back into the intake somewhere. What's your intake setup look like?

jake15 · Post by **jake15** » Sun Sep 05, 2004 2:20 am

in my experimenting today i figured out that the bov is meant to stay open at idle, but it didnt feel like it was sucking air in, just blowing it out. there is no way to plumb the bov back into the intake tract, the throttle cables are in the way (almost up in the bov). i made the bov stay shut at idle by removing the hose that connects to the top of the bov and blocking it off with a bolt, and now it idles fine and releases the pressure, just not as well as it does with the hose connected, which brings me to my question. would an aftermarket atmospheric bov work? i have a picture and a video of the setup if someone could host the video for me. thanks,

jake

vrg3 · Post by **vrg3** » Sun Sep 05, 2004 3:17 am

Without that hose in place your blowoff valve is acting as a relief valve, basically venting any boost above probably around 7 psi or so. So this isn't an acceptable solution.

An aftermarket atmospheric valve might work if it's built right. Phil uses an HKS SSQV or whatever and it seems okay.

The simplest/cheapest thing to do, though, if you don't want to figure out how to recirculate around all the obstacles, would be to put a check valve on the stock WRX valve's outlet. I haven't tried it myself, but I think McMaster-Carr part number 46835K53 might fit well with a little massaging.

jake15 · Post by **jake15** » Sun Sep 05, 2004 4:38 am

what is a check valve? im thinking its something that will restrict the flow one way and allow it the other. then it will work perfect at idle and as soon as the positive manifold pressure is present it keeps the bov shut to attain the heavy boostin

edit: would this one work? part # 7933k29

vrg3 · Post by **vrg3** » Sun Sep 05, 2004 3:37 pm

Yes, a check valve is a one-way valve. So you'd leave the valve controlled by the pressure differential across the throttle plate, but it would only be able to vent pressure; it wouldn't suck in any unmetered unfiltered air.

Part number 7933K29 has 1/4" pipe thread fittings on it. I think that would be too small... the valve's outlet is 19mm, isn't it? Or 3/4" (which is almost exactly the same)?

The part number I suggested is meant to be socket-welded to 3/4" PCV, so it might fit neatly over the BOV's outlet with a little shaving.

Or you could get one with 1/2" male pipe threads, (which have an outer diameter of approximate 3/4") and use a short piece of 3/4" ID hose to connect it to the BOV.

jake15 · Post by **jake15** » Sun Sep 05, 2004 6:27 pm

nothing will fit on the end of the bov outlet where its supposed to recirc. the throttle cables are right by the opening and there is no way to put anything on there. when i can get the pics off of my brothers camera and posted you'll understand what i'm talking about. i'm talking about putting a check valve on the hose that connects to the top of the bov (the hose that opens the valve when negative manifold pressure is present) so when it try's to suck it is just like plugging it with something but once it hits positive manifold pressure it clamps the bov shut.

vrg3 · Post by **vrg3** » Sun Sep 05, 2004 7:03 pm

Oh.

A check valve in the vacuum hose won't help. For one thing, the actual amount of airflow is very small so you'll basically just end up storing boost inside the chamber of the BOV, preventing it from ever opening. For another, even if you had a pressure relief it still wouldn't function right since you need the BOV to open on vacuum.

Maybe you should see if you can buy or fabricate a little cover for the BOV flange with a 19mm nipple on it... I've seen them used on WRXes for fitting aftermarket blowoff valves. Then you could use your stock valve.

Or maybe you could block off the flange entirely and figure out how to install a 19mm nipple in the compressor-to-intercooler pipe.

BAC5.2 · Post by **BAC5.2** » Mon Sep 06, 2004 1:02 am

Like Vikash said, I am using an HKS SSQV. Works perfectly. No effect on anything, noticeable. Even revving in neutral, where a regular stock BOV would just leak to high heaven.

I would only go with quality aftermarket BOV's. Simply because you want something to react very quickly to prevent any possible seepage. I like the SSQV because of the diaphram style valving (rather than push-valves that can leak at high boost). We don't quite make the boost that would cause float in cylinder style valves, but that's just something I like. Anything dual-stage (SARD, TIAL, and HKS) usually reacts a bit better and faster than cylinder style valves (like TurboXS and such).

jake15 · Post by **jake15** » Mon Sep 06, 2004 2:13 am

i was looking at a turboxs type h rfl, do you think that would work good up to about 14 psi?

BAC5.2 · Post by **BAC5.2** » Mon Sep 06, 2004 4:18 am

Yea, but the RFL is OUTRAGEOUSLY loud. It's to the point that it's just fucking annoying. I know. TurboXS is just down the street from me.

The TXS valve is a piston style valve, so it still has the possibility of creeping under long term, high boost use (i.e. Full boost in 5th gear, on the highway). It's all a matter of whether or not you overcome the spring tension. You should be safe at 14psi, but the RFL valve is a "high power" valve, meaning it's got a larger surface area piston so it reacts slower (big pistons don't move as quickly as small pistons). This allows the potential for compressor surge as the valve does not move quickly enough with low boost.

I like my HKS valve though. It's super sweet.

jake15 · Post by **jake15** » Mon Sep 06, 2004 5:40 am

i would get an hks one, but i cant find one for a good deal, i can find the turboxs ones for $100, all the hks ones are $175+. i'm looking for something thats 100% atmostpheric so i dont have to worry about it being open at idle. i see some on ebay that are some cheap generic brands for like $50 but i wouldnt trust them on my car. i've yet to hear a turboxs bov, but i do not mind loudness. if it doesnt work out i'll have to live with it till i can save up enough money to buy a different one (i'm only 16 w/o a job) haha. any more suggestions are welcome. thanks for all your help

BAC5.2 · Post by **BAC5.2** » Mon Sep 06, 2004 6:20 am

Well, the TXS valve will work, it's just personal preference speaking. The RFL is REALLY FUCKING LOUD (as the monker would suggest). WAY to loud for my tastes, just like the RFL exhaust.

Certaintly attracts attention though.

You get what you pay for, this is another example. The HKS is a superior valve, hence the higher cost.

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arggggg i need more help!!

arggggg i need more help!!