BOV Issues St185 GT4 Celica

[asweetdude]

Hey all,

yea im a noob to toyspeed but not to toyotas...

Just wanting to know as i have just installed a BOV on a st185 GT4 and well, its not doing what it should.

I have run an extra pipe off the front elbow bend of the factory top mount IC, and thats all well and dandy. The vacuum i have run is off a blanked off one at the back (and sort of underside) of the intake plenum, this has quite a strong vacuum.

My problem tho is that the BOV opens when it should but takes abouut 2-3 seconds to close and makes a gay ass whistling noise when it does...

I suspect this is because of the rubber rings in the BOV (yes it is a cheap one)

Has anyone else had this problem or similar? is it possible that its caused by too much vacuum?


Can anyone help??!!

[MrOizo]

might need to tighten up the spring? if thats possible on the cheapo BOV?

[aesc]

Is the vacuum source youve tapped into before or after the throttle butterfly. It should be under or after it, but im sure if you took that off where the factory BOV was its prob not an issue

Some BOVs can have the tension adjusted on them, maybe try this if you can

[asweetdude]

Yes the vacuum is after the throttle body.

If i adjust the spring (spent about 3 hours f&^King with it) it iether stops it opening at all or allows it to open easier, this is fine, the problem is that it takes ages to close, most BOV's close asap as soon as the pressure changes in the intake mine tries to, but is coming into some resistance.

Am looking at other valves taht dont use rubber bushes/seals. but was hoping to confirm that the valve is the prb before i shell out $250 for one from FBI.

[slighty_sykotic]

To confirm that its the BOV, change the vaccuum feed to the factory one.

If it still does it, spend your $250.

[asweetdude]

am pretty sure its the valve, as the vacuum im using is a spare factory one. and it still does it even with the vacuum pipe disconnected from the valve. now i have the dilemma of what to buy, repco has a racepro one for $208 and fbi has a GFB one for $250, anybody got any recommendations?

[Boosted_162]

I had a GFB Mach 1 on my first ST185, its makes a plain pssshhh noise, but its pretty loud (louder if you run more than standard boost)

[aesc]

Id look on trademe for one before going and paying retail. I paid $80 for a near new GFB valve works fine. Theres always plenty on there

[Adydas]

where the factory BOV was its

They dont run one factory..

[Alex B]

Really?? Gen 1 & 2 MR2 do, didn't think there were any differences between the 3s-gte's ??

[groupagt4]

dont waste ure time.bov makes your car run bad,throws the a/f ratio out.

[UTERUS]

dont waste ure time.bov makes your car run bad,throws the a/f ratio out.

And compressor surge isn't?

[fivebob]

poorly installed, or cheap bov makes your car run bad,throws the a/f ratio out.

Corrected for truth.

A properly installed BOV will not have any effect on A/F ratios, except if you vent it atmosphere, even then it's only goes slightly rich between gear changes.

[Malcolm]

Really?? Gen 1 & 2 MR2 do, didn't think there were any differences between the 3s-gte's ??

no differences in the block/head, but plenty of differences in stuff that bolts onto them (ic/piping, alternator, valve cover, thermostat housing, coolant elbow, crank pulley, throttle body inlet to name a few)

the first gt-four to get a factory bpv was the st205

[RS13]

Yeh, you get what you pay for eh, I bought a cheap nasty BOV off tardme, threw it on my ET turbo and found I had a massive flatspot after shifting, watched the BOV do its' thing, turned out the brass piston in the middle was slightly too large for the aluminium body, so it kept nipping the sides and jamming momentarily after releasing the boost, therefore also letting out the new intake charge!

Mine made a stupid whistling noise too, sounded kinda like, "pssSSHHHHEWWWwwww", so I sanded it down, fixed it good!

[Prymal]

good escuse for a frontmount and a Straight intake pipe to your afm

Now , when i did this on my St185 , which does not run a BOV standard as pointed out , i tapped in before the throttle body for the BOV unit , ran the plumb back setup into a straight intake pipe , and fed the vaccum source from the large plug located at the back of the intake plenum , if you reach down behind it between the firewall and plenum you will find the right source to tap into

I can provide a pic of the full frontmount piping setup from above if you get stuck

With the standard topmount cooler - get the BOV flange welded into the piping between turbo and core - as thats about the only place you can put it - but youll have to figure a way of routing it back nto the intake piping after AFM and before the turbo inlet otherwise it will make the ecu have a little hissy and make things run richer ..

Even better- pss off the AFM , throw one of the popular link ecu's in ( or the wolf v400 plug and play unit) , make it redundant - and run a much happier and more accurate map sensor setup , with a much mor accurate way of measuring intake temperature to , after turbo and intercooler

[Norty]

good escuse for a frontmount and a Straight intake pipe to your afm

Now , when i did this on my St185 , which does not run a BOV standard as pointed out , i tapped in before the throttle body for the BOV unit , ran the plumb back setup into a straight intake pipe , and fed the vaccum source from the large plug located at the back of the intake plenum , if you reach down behind it between the firewall and plenum you will find the right source to tap into

I can provide a pic of the full frontmount piping setup from above if you get stuck

With the standard topmount cooler - get the BOV flange welded into the piping between turbo and core - as thats about the only place you can put it - but youll have to figure a way of routing it back nto the intake piping after AFM and before the turbo inlet otherwise it will make the ecu have a little hissy and make things run richer ..

Even better- pss off the AFM , throw one of the popular link ecu's in ( or the wolf v400 plug and play unit) , make it redundant - and run a much happier and more accurate map sensor setup , with a much mor accurate way of measuring intake temperature to , after turbo and intercooler

Hey would you be able to post that pic anyway i would be keen to look as i am going to Front mount soon

Cheers

[asweetdude]

So after alot of snooping around, and investigating other cheaper options....

And thanks classique, you have confirmed i have put the valve in the righ (only) place you can put it. and used the correct vacuum source.


Ive foudn that the cheaper valves on tardme $50-$100 that are billet aluminium and small enough to fit comfotably inside a tennis ball (or similar to that size... are garbage, i did a bit of web research and these valves brass piston, or aluminium doesnt matter, are only rated for 3-4psi...

dont know many cars that run that lower amoutn of well.. i dont wanna call it boost as i could sneeze harder.

either way, dont buy em , they are grabage, supercheap auto even sells a monza one which is identical.

So i went to FBI today and bought a GFB Bovus Maximus... big red fire hydrant looking thing. Works well, alot more complicated internals, 2 ways of adjustment and it is way louder anyway.

my advice... dont waste money on cheap stuff. $250 is a good price to pay for a very high quality product.

Only prob is that it only just fits in the gap between the IC, turbo, radiator pipe, and fuse box. bonnet actually touches it when i shut it.

[Prymal]

will post a pic up over the weekend of the setup looking down onto the engine

[Norty]

will post a pic up over the weekend of the setup looking down onto the engine

Thanks alot