[335boosted2Dmax]

I hope people know that this car is a closed loop system, in which case a blow off valve will do damage to the car in the long run, what this system needs is a Diverter Valve which Diverts the air back into the system and does not release it..........I just hope people aren't just going out to get the BOV's just to get the noise.........just wanted to start a thread about this because people seem to be running out to get a BOV as soon as they get a 335i............

[Zeiss]

Good info! BOV is totally unnecessary for that engine layout.

[SoCal335i]

Yes you are correct the bov does not do anything for performance. It is for the noise. Thats the only part im going to agree with you. Other than that it doesnt matter whether its closed loop or not, if you go with the right bov setup you will not cause surge and wont damage anything on the car. Furthermore when you blow off atmospheric instead of diverting you are running cooler because your not recirculating the uncompressed hot air thru the diverter valves, instead you are blowing it out. With the tial bov you might get some surge with the wrong spring and its a 50mm valve (the largest one in a bov) which is a little overkill. The hks is a well designed bov for this type of low boost setup and remains completely shut during idle because of the pull trigger type design and wont leak boost.

[335boosted2Dmax]

The BMW turbo system is a closed loop system by which all unused boost that is spooled during off throttle and gear shifts must be re-routed within the system; it cannot be vented to the atmosphere due to the dependence on the MAF and ECU to properly read and interpret air flow dynamics within the intake tract. Therefore BOV's (Blow-Off Valves) are not used because they create a rich air/fuel condition (i.e. less air to fuel ratio) which will damage the catalytic converter, create soot on the exhaust pipes, and cause occasional misfiring (due to the purged air) which will result in ECU miscalculated timing adjustments and other errors.

[SoCal335i]

I heard that the sensors dont pick up anything from the diverters and that its on a map sensor system not maf??

[335boosted2Dmax]

I'm not positive about that, I just assumed MAF.......

[SoCal335i]

If im right then it in fact doesnt do any harm to the car or affect the A/F ratio, And then you too will buy one

[335boosted2Dmax]

The only problem, it is yet to be seen, I'm very iffy of the BOV with this closed loop system, I would rather put my money towards a TURBO back exhaust with a nice 3 inch wide Down Pipe

[SoCal335i]

It is on map sensor check this post out. I hear what you are saying but im spending a lot of money on this car so a $450 bov isnt going to stop me from getting anything else. You're not going to be able to fit 3" downpipeS on this car... Not enough room... they would hit each other where they connect to the turbos.

http://www.e90post.com/forums/showth...hlight=e92+map

[335boosted2Dmax]

I still think the car is going to run rich even though you may not get any CEL's or error codes.....i don't know we will see eventually

[RetroGamerJP]

Originally Posted by 335boosted2Dmax

I'm not positive about that, I just assumed MAF.......

You should not make such a bold statement as your OP and then later say you are "Assuming" anything. System is MAP based.

Whether you would install a BOV or not is one thing but to tell others they are damaging their vehicle when you do not have all the facts is irresponsible.

Use the search, it's been discussed.

[wj4]

Originally Posted by jp335i

You should not make such a bold statement as your OP and then later say you are "Assuming" anything. System is MAP based.

Whether you would install a BOV or not is one thing but to tell others they are damaging their vehicle when you do not have all the facts is irresponsible.

Use the search, it's been discussed.

Plus 1,000,000. How are you going to make such a bold statement based on assumptions. And the 335i is NOT a MAF system. My current car is a MAF system and you can't even run a VTA BOV, it will stall on you at random times.

[purplewidow]

here is the best sounding one that i have heard!!!!!still i would never rice my beamer!!!! tune but not rice!!!

________
Volcano Vaporizer

[SoCal335i]

Originally Posted by purplewidow

here is the best sounding one that i have heard!!!!!still i would never rice my beamer!!!! tune but not rice!!!

That one has the Greddy type rs bov on it... Thats pure rice buddy. Its not good for this car i dont think, i saw that you can buy an extension for it, you screw it on the front and makes it like a pull trigger type like the hks so it stays closed in idle so it doesnt make your rpms fluxuate at a red light. It might not sound the same with that extension on though.

[wj4]

Just my 2cents, but the Greddy BOV's really suck. I've had 2 myself and the diaphragm on both went out causing a major boost leak...from 24psi to about 13psi. 4 of my friends also had the diaphragms on their type s and rs ripped.

I must be one of the few who thinks that the 335i has an integrity level it should maintain. And I'm almost certain those who go with VTA will get bored of the sound extremely quick. Everytime you let off the gas, you will hear it.

[Ultimate Racing]

Originally Posted by 335boosted2Dmax

I still think the car is going to run rich even though you may not get any CEL's or error codes.....i don't know we will see eventually

The engine runs speed density (MAP sensor based). The engine will not run richer as the metering is done post BOV.

Darryl
www.ultimate-racing.com

[A. Hansen]

The 335i uses bosch diverters

They choose them because of enviorment and noise.
So it's no problem to blow to air.

With a maf (VAG cars) only closed loop works because it's measuring mass air

[SoCal335i]

I love being right!!

[CASHBY]

so would 2 forged 004 BOVs work, or would you need the new pipe to only have one BOV?

right now i run a Forged 004 BOV on my A4.... i have no issues with it and its runs a MAF.

Here is the 004 Valve



Made from billet aluminium, this atmospheric diverter valve dumps the charge-air to atmosphere creating the "Whoosh" sound when the throttle is lifted. This increases both quicker throttle response and higher clamping load to maintain boost pressure more reliably.

Unlike single piston or diaphragm diverter valves, this uses counter balanced springs and dual pistons to prevent the valve from leaking air into the intake system at idle. This prevents our diverter valves suffering any of the failures associated with single piston and diaphragm type diverter valves.

http://www.ecodetuning.com/shop/cart...t_detail&p=436

[schneid4323]

Originally Posted by CEA 3

so would 2 forged 004 BOVs work, or would you need the new pipe to only have one BOV?

right now i run a Forged 004 BOV on my A4.... i have no issues with it and its runs a MAF.

Here is the 004 Valve



Made from billet aluminium, this atmospheric diverter valve dumps the charge-air to atmosphere creating the "Whoosh" sound when the throttle is lifted. This increases both quicker throttle response and higher clamping load to maintain boost pressure more reliably.

Unlike single piston or diaphragm diverter valves, this uses counter balanced springs and dual pistons to prevent the valve from leaking air into the intake system at idle. This prevents our diverter valves suffering any of the failures associated with single piston and diaphragm type diverter valves.

http://www.ecodetuning.com/shop/cart...t_detail&p=436

I wanna hear a video before I jump the gun on this...

[CASHBY]

I have it on my A4...it isnt like a BOV sound...its more of a WOOOOOOSHH sound.

I like how it sounds though.

but i am not sure if it will even workwith our cars... you would have to run 2 of them.

[A. Hansen]

Hi,

Who did your tuning on the a4 ?

It's possible to reprogram the motronic ECU
then the MAF sensor is shut off... the injection /ignition etc... is pure lambda based.

Only a few companys do this.

If they didn't do this you get 100% SURE CeL'S (CHECK ENGINE LIGHT)