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Lagos
12-03-2004, 09:16 PM
my setup is...

2nd gen 3sgte at 11psi
fmic with 2.25 piping
hks bov (vented)

when driving i could hear a lot of hissing from the car, and the throttle response was crappy. after checking for any boost leaks, i decided to see how the car would perform without the bov working. i disconnected the vac line that runs to the bov and caped it off. now the car fell soooo much better. there is no loud hissing, just the normal spool and throttle response is great.

are there any risks to running the car the way i have it now? i know the correct thing to do is to recirculate the bov,i plan to do that. for the time being, could i just run it with the bov disabled?

eveyone who has a 3s, give this a try. youll be amazed at how much better the car feels.

ChrisD
12-03-2004, 09:24 PM
There's no real harm to running no BOV. Remember that stock, your engine doesn't even have one. But it sounds like something funny is up with your bov. Could the adjustment be too loose? It shouldnt affect your car for throttle response at all.

Lagos
12-03-2004, 09:36 PM
on the hks there is a screw, i had it nice and tight, but not turned 100% all the way, maby like a little less then 1/4 of the threding showing.

i just conneced the bov back up, and made that screw stick out more, seems to have helped but still not as good as it was disabled.

by throttle resoponse, i realy mean the way the car feels when you pussy foot the gas pedal during daily driving. since the bov opens up when it sees a change in the vac, giving it a little gas, shifting, and giving it gas again, seems to bog the car down when vented to the atmospehere.

yeah, i figure it couldnt hurt the motor to be without the bov, but could it maby cause problems if i start running more boost later on? maby IC piping will be more likely to come loose? is a BOV more then a noise maker?

Mike431635
12-03-2004, 11:27 PM
I can solve all your problems: buy a TurboXS unit :D

I have been in love with those valves ever since I heard the Type-H on Tom's (galcrazi) 3SGTE-swapped 5th gen GT.

Mike431635
12-03-2004, 11:28 PM
Or just buy this GoFastBits WRX valve I've got for sale for my gf's bro, cut off the flange, and weld it onto your pipe :)

Schmleff
12-03-2004, 11:32 PM
Or just buy this GoFastBits WRX valve I've got for sale for my gf's bro, cut off the flange, and weld it onto your pipe :)

Or sell the wrx one to me!

I know this is going to sound dumb, but I thougt it has some type of recirculating valve stock? I don't recall, I did not remove the engine from our doner car. It was already out.

Lagos
12-03-2004, 11:35 PM
Schmleff, i just gave a proper education on this topic to your buddy johnL, hahaha

the stock 1sgen and 2nd gen alltrac did not come with any type of bov. the 2nd gen mr2 and the 3rnd gen gt4 did have a factory one.

nuclearhappines
12-03-2004, 11:58 PM
still a bov increases the life of your turbos.

You need to adjust your bov so that it's not leaking air that's all.

try not to run without a bov for an extended period of time.


-nuke

bloodredgt
12-04-2004, 12:33 AM
Are any of you guys running with open waste gate?

Luni
12-04-2004, 12:40 AM
Are any of you guys running with open waste gate?

What do you mean open wastegate?

If you run with the wastegate OPEN the turbo wont spool very fast if at all.

If you run with the wastegate DISABLED the turbo will spool WAY more than 7 psi.

Are you talking about disabled wastegate?

Lagos
12-04-2004, 01:41 AM
nuke, my motor was driven around for 60,000 miles in japan with no bov, so what im doing, cant possibly harm it. if anything, running extra rich from blowing out unmetered air was doing it more harm.

i just got back from driving it some more with no bov...man, its like a whole new car. so much faster then before. just going through the gears the car keeps a constant pull. before i would have wait for the spool up, shift, and bog down a little. now its just, spool up and for get it cause it pulls cosntant though all the gears.

other cool thing is that my car no longer draws attention to me. my exhaust sounds like stock and all you hear is a nice faint sound spool. it feels like such a sleeper.

i plan to drive around like this for the next week or so and then correctly recirculate the bov and hook it back up.

Playfortoday
12-04-2004, 02:11 AM
I think what nuke is getting at is that you are running above factory boost which is more strenuous on the turbo than it was at stock boost levels. Any way you slice it, a bov will lengthen the life of a turbo.

T-spoon
12-04-2004, 03:50 AM
Eeek, guys, not talking about ENGINE damage here, but turbo damage. If you don't get pressurized air out of the intake pipe when the throttle plate closes, it has to go somewhere. If your piping is all secure and tight, that somewhere is back the way it came. Compressor surge is bad for turbos, the engine couldn't care less, the throttle plate is closed. My alltrac only had 120k miles when I got it and had never been run above factory boost, never had a BOV and one day..the whole danged shaft snapped. We've pondered why Toyota didn't put a recirc unit on the alltracs, but it certainly isn't because there's no reason to. After all, they put them on later GT4s, MR2s, Supras, etc. I'd just live with it for now and get the recirc done asap.

Schmleff
12-04-2004, 06:03 AM
Are any of you guys running with open waste gate?

Do you mean like a divorced waste gate? Kinda tough to do with the way the turbo is set up. Some of the supra chaps have done some welding to the housing and ran a seperate pipe though.

Luni
12-04-2004, 04:32 PM
Yeah Lagos man, we arent trying to sound mean or nothin, but you are surely hurting your turbo gradually by not having yoru BOV open.

I mean whats the point of even having one. It just sounds like you got a cheap one. Get a Greddy TypeS or a HKS SSQV or something like that. Those units work fine on our cars.

T-spoon
12-04-2004, 04:37 PM
Heh, I think he actually does have the HKS ssqv, it'll be all good when it's recirc'ed I reckon

Luni
12-04-2004, 05:29 PM
Yeah.

Actually Ive read that when our cars go into open loop/closed loop mode the blow off valve opens and stuff, and if youre recircing and you are using a push shut unit (the SSQV is modeled JUST like a stock MR2 valve where it cannot leak if there is boost cause the harder you boost, the harder you push against the seal). Being that its modeled that way, I thought there were 2 lines you could potentially hook up depending on how you want it to work, and it could be sticking open on regular driving thus causing the engine to run rich.

Lagos
12-05-2004, 03:38 AM
Actually Ive read that when our cars go into open loop/closed loop mode the blow off valve opens and stuff, and if youre recircing and you are using a push shut unit (the SSQV is modeled JUST like a stock MR2 valve where it cannot leak if there is boost cause the harder you boost, the harder you push against the seal). Being that its modeled that way, I thought there were 2 lines you could potentially hook up depending on how you want it to work, and it could be sticking open on regular driving thus causing the engine to run rich.


bingo. i think this is what my problem is. i just realized that i had my bov hooked up to one of the lines on the round idle up valve (the thing next to the trubo pressure sensor). im guessing that is what may be causing it to open too soon. tomorrow i will try it again with it hooked up directly to the manifold. the bov i have is the hks.

just so you guys understand, im doing this as sort of a test/experiment to see why i was hearing a lot of hisss under boost. i though my IC piping was leaking, but it tunrned out to be the bov. so far ive driven 2 days with no bov. before, my car would bog down when i shift, run like total crap when the engine was cold, and sometimes need a little gas to start it up on a cold morning. disabling the bov fixed alll of those problems!!! im going to hook the bov and recirculate it from now on. i recomend everyone with a vented bov, to give this experiment a shot and see how much better your car feels.

Supersprynt
12-06-2004, 02:15 PM
What exactly is the experiment? To hook it up correctly, or to recirc it?

Lagos
12-06-2004, 04:12 PM
to see what im missing out of by having the bov vented, and to see why my car just didnt feel right when driving.

in order for me to recirculate the bov, i have to move the battery to the trunk and build a custom intake. so, before i did any of that, i wanted to know if it was worth all the hassle.

i played around with my bov some more and found out that the threading on the adjustment screw is kind of fucked up. maby this is why it wasnt working out for me as good as it is for other people.

anyone else have issues with their hks bov?

gt_turbo
12-06-2004, 06:13 PM
you can get a custom straight intake pipe from this guy on alltrac.net for $50 and he will also weld on an extra bung for recirc. his sn is bayarea or something like that. his stuff looks good!

carlosfandango
12-06-2004, 08:25 PM
Lagos, as i read the thread, i was thinking - he's notgot it connected correctly -, low and behold, yup.

the bov will not affect performance, it closes when you hit the throttle and only opens when the throttle butterfly closes. its a one way relief valve saving your turbo from compressed air lash.

Mine runs fine with the bov, at first i thought the noise was ricer but now i quite like it, i purposely accelerate and snap off the gas to close the butterfly in order to PSSSSTT past others when overtaking. The looks on their faces are a picture.

Enjoy.