[joec500]

Hmmmm stock DV'S work great for me!!!

[XPO186]

What's up Joe! Yes that's rite... I am the MUNI bus you hear behind you.

Off topic: you in NYC yet? Sounds like your weekend is gonna be a blasty blast.

Hey man, can you shoot me your number again? I updated my stupid iphone's firmware and didn't backup my data. Lost a bunch of data...

Yes stock DVs for the win, or something...!

[Terrance28]

Originally Posted by packinDSS

Everything I've read shows no advantage of using a BOV over DV and vice versa other than BOV's on our cars suck in unfiltered air. Correct me if I am wrong.


I personally do not like the BOV vacuum cleaner sound I associate them with and they suck in unfiltered air into the engine.

A bov will not suck in air on this car, please read sparkys response.

[Terrance28]

OP quit the guessing work on whihc springs you need and invest in a synapse BOV, and you won't have to worry about this ever again.

http://www.e90post.com/forums/showthread.php?t=312105

[Terrance28]

Originally Posted by joec500

Hmmmm stock DV'S work great for me!!!

Trust me once you start pushing any serious boost they are gonna start blowing open.

[XPO186]

Originally Posted by Terrance28

OP quit the guessing work on whihc springs you need and invest in a synapse BOV, and you won't have to worry about this ever again.

http://www.e90post.com/forums/showthread.php?t=312105

Ha ha, i should...

The synapse looks like a really nice piece. I'm just not sure what's up with the apparent smear campaign they are running against the TiAl valve. All their youtube videos seem to show how shitty the TiAl valve is (apparently?).

[s1cke92]

335i are my first turbo cars. i use to have aa bov, i've bought it used, all i did was install it. what springs are you guys talkin about? or did aa bov dont have springs?

[XPO186]

No springs for the AA bov. Their kit is specific to these cars though so it's probably already dialed in.

[s1cke92]

kool! im getting my aa bov back from mandeep lol.

[XPO186]

So I got the 11lb spring in the BOV and it's working MUCH better than the previous 9lb spring.

Throttle response is much improved... it feels more like the Forge DV setup MINUS the leaky stock chargepipe connection.

On the lighter spring when getting on it, I noticed a bit of lag before boost came on as if the BOV would hang open for just a second before closing and allowing boost to build. Now, the response is instant because the the BOV stays closed at idle and cruise.

Even with a different spring installed, the BOV is still really quiet. So quiet in fact that I suspected that the BOV may not even be dumping pressure but that is impossible. Even with mild levels of boost, releasing the throttle causes vacuum to rebound to >20 in/Hg (actually around 23-24 per my boost gauge). Since the new spring is rated at -22 in/HG and the engine idles at around -20, the BOV remains closed until vacuum exceeds the springs rating. Therefore, it only opens right after throttle closure when there is greater than idle vacuum.

The heavier spring has also all but ELIMINATED the fluttering when shifting after accelerating with part throttle. I was able to get the flutter to occur deliberately by just "feathering" the throttle on/off boost but even that was quite difficult and no one drives like that.

In all, I am very pleased with the *correctly* tuned Tial. IMO, the performance and throttle response is right on par with the Forge DVs with yellow springs... only with a bit more noise. And actually, my exhaust is already so loud you can't hear it dump anything less than 8psi... and I barely EVER see boost during daily driving. Tial Sport has a great reputation for their FI parts and their BOVs defnitely perform.

I may go to another BOV in the future... but the only reason I would do that is for MORE noise. However, this one works perfectly.

[john boxter]

oh wow which spring did you change to what color? and so if you have a bov does it go off everytime you switch gears (in a manual car)? like in traffic will it constantly be going off?

[Zeph]

Originally Posted by john boxter

oh wow which spring did you change to what color? and so if you have a bov does it go off everytime you switch gears (in a manual car)? like in traffic will it constantly be going off?

you gotta build boost before it will make noise. Unless you floor it in traffic then slam the brakes I don't think you will be boosting. When you WOT and rev it up to 4k+ RPM's and then shift is when it will be the loudest... especially if you are running more boost. Stock 8.5psi isn't going to make much noise really.

[john boxter]

ye well im running a jb3 i feel like if its constantly going off that might get annoying so you have to build a little huh so i usualy drive around 2700 rpm and ill shift at like 3000 wil it be going off everytiime do you know?

[XPO186]

Originally Posted by john boxter

oh wow which spring did you change to what color? and so if you have a bov does it go off everytime you switch gears (in a manual car)? like in traffic will it constantly be going off?

I went from the 9lb spring to the heavier 11lb spring (which is what tial recommends for our cars based on engine vacuum).

Honestly, during daily driving the BOV operates just as silently as diverter valves. Not noisy at all. If you have a very quiet stock exhaust, you could maybe hear them "breathing" a bit more but definitely no super loud WHOOSHing going on. My exhaust is loud enough to drown out dumping anything less than 5ish psi.

You have to build a decent amount of boost before you hear it dump and even then, it sounds about as loud as diverter valves dumping the same amount of boost. I'd say it's only louder than my Forge DVs when dumping 10psi or higher. Anything below that you could hear, but it's pretty mild sounding.

Originally Posted by Zeph

you gotta build boost before it will make noise. Unless you floor it in traffic then slam the brakes I don't think you will be boosting. When you WOT and rev it up to 4k+ RPM's and then shift is when it will be the loudest... especially if you are running more boost. Stock 8.5psi isn't going to make much noise really.

Yup. Pretty much what he said. But IMO, stock boost is still audible... just not loud.

Originally Posted by john boxter

ye well im running a jb3 i feel like if its constantly going off that might get annoying so you have to build a little huh so i usualy drive around 2700 rpm and ill shift at like 3000 wil it be going off everytiime do you know?

Don't worry, you'll be fine. You can even drive around the boost if you want.

[john boxter]

what do you mean drive around the boost?

[XPO186]

You could accelerate more gradually so that you do not cause boost to build. Think economy driving and short shifting...

Do you have a boost gauge? The boost comes on pretty seamlessly on these cars so you may not be able to tell at low levels of boost.

[bulldog_yyc]

Originally Posted by XPO186

So I got the 11lb spring in the BOV and it's working MUCH better than the previous 9lb spring.

Throttle response is much improved... it feels more like the Forge DV setup MINUS the leaky stock chargepipe connection.

On the lighter spring when getting on it, I noticed a bit of lag before boost came on as if the BOV would hang open for just a second before closing and allowing boost to build. Now, the response is instant because the the BOV stays closed at idle and cruise.

Even with a different spring installed, the BOV is still really quiet. So quiet in fact that I suspected that the BOV may not even be dumping pressure but that is impossible. Even with mild levels of boost, releasing the throttle causes vacuum to rebound to >20 in/Hg (actually around 23-24 per my boost gauge). Since the new spring is rated at -22 in/HG and the engine idles at around -20, the BOV remains closed until vacuum exceeds the springs rating. Therefore, it only opens right after throttle closure when there is greater than idle vacuum.

The heavier spring has also all but ELIMINATED the fluttering when shifting after accelerating with part throttle. I was able to get the flutter to occur deliberately by just "feathering" the throttle on/off boost but even that was quite difficult and no one drives like that.

In all, I am very pleased with the *correctly* tuned Tial. IMO, the performance and throttle response is right on par with the Forge DVs with yellow springs... only with a bit more noise. And actually, my exhaust is already so loud you can't hear it dump anything less than 8psi... and I barely EVER see boost during daily driving. Tial Sport has a great reputation for their FI parts and their BOVs defnitely perform.

I may go to another BOV in the future... but the only reason I would do that is for MORE noise. However, this one works perfectly.

bumping this old thread as I ran into the same issues - 11lb spring on order! Will report findings after I switch the springs out.

[bulldog_yyc]

bumping the old thread again. 11lb spring working perfectly for past 3 months or so. Throttle response has improved over 9lb spring by an appreciable amount. It is slightly louder than the 9lb and absolutely no sign of flutter, which was sometimes there with the 9lb spring (weird result but same experience) as user above.

Conclusion - if you are tuned and have a Tial BOV, make sure to get the 11lb spring. Picked mine up on ebay for about $40 shipped. Be careful when swapping out your BOV spring - the Tial vband clamp is somewhat tricky to remove from the CP (Stett in my case) without dropping parts all over the engine bay. I ended up having to order a new vband clamp assembly/bolts direct from Tial because I was a clutz and dropped some stuff.

[bimmertt]

Originally Posted by turkish335

bumping the old thread again. 11lb spring working perfectly for past 3 months or so. Throttle response has improved over 9lb spring by an appreciable amount. It is slightly louder than the 9lb and absolutely no sign of flutter, which was sometimes there with the 9lb spring (weird result but same experience) as user above.

Conclusion - if you are tuned and have a Tial BOV, make sure to get the 11lb spring. Picked mine up on ebay for about $40 shipped. Be careful when swapping out your BOV spring - the Tial vband clamp is somewhat tricky to remove from the CP (Stett in my case) without dropping parts all over the engine bay. I ended up having to order a new vband clamp assembly/bolts direct from Tial because I was a clutz and dropped some stuff.

So the TiAl that comes with the STETT kit has a 9 lb spring?

[runz12s]

about to buy a tial q from extreme psi, guess ill be ordering the 11lb spring!

[Syndicategt]

Originally Posted by runz12s

about to buy a tial q from extreme psi, guess ill be ordering the 11lb spring!

I have one if you want. I've been using the OP's TiAL BOV for the better part of 2 years now with the 9lb spring and have not had any issues. I used to get the ocasional flutter, but that seemed to have stopped. Let me know though if you want it still.

So the TiAl that comes with the STETT kit has a 9 lb spring?

Not sure about Stett but ER's TiAL BOV comes with the 9lb spring and they use the same one on their time attack car.

[runz12s]

Originally Posted by Syndicategt

I have one if you want. I've been using the OP's TiAL BOV for the better part of 2 years now with the 9lb spring and have not had any issues. I used to get the ocasional flutter, but that seemed to have stopped. Let me know though if you want it still.

Not sure about Stett but ER's TiAL BOV comes with the 9lb spring and they use the same one on their time attack car.

Damn I literally ordered it 20 min ago wish I saw this