BOVs: To Vent, or Not to Vent? That is the question! (FM Live)

To vent or not to vent? That is the question! This week on FM Live, Jeremy Ferber talks us through turbo Blow Off Valves, and the pros and cons of recirculating that pressure instead of venting your bov to atmosphere.
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[@sshhddoo9892]

such a gorgeous NA

[@FlyinMiataVideo]

We've got a virtual tour video if you want to see more of it! kzbin.info/www/bejne/b4LXeXpqgL6bqq8

[@GOINFINITI]

Excellent explanation.

[@FlyinMiataVideo]

Thanks for watching!

[@carsondes7722]

This is a very informative video. Thank you for the details and the explanations of the different uses and how they operate.

[@FlyinMiataVideo]

We appreciate the kind words! Thanks for watching.

[@ExCordeEnt]

This was super helpful. I dont have a miata. I have an 87 300zx. The guy i bought it from added an intercooler setup and with that, a bov. The afr has always seemed off to me (runs rich). I am currently replacing everything from the intake, intercooler, turbo and exhaust. My new bov comes with everything to recirculate as an option. I started doing some research and from watching your video, it seems that vent to atmosphere may actually be what was causing some of my issues. On my new setup im going to plumb into my intake and recirc. Thanks for this info!

[@FlyinMiataVideo]

@ExCordeEnt If your Z is still using the stock mass airflow sensor, running a vent-to-atmosphere blow off valve will definitely cause your fuel trims to be off.

[@sylvaintexier8609]

Thank you

[@FlyinMiataVideo]

Hopefully it helped!

[@baltod4978]

As a S1 Kit owner- it'd of been great to hear what the BOV sounds like, since it comes in the kit

[@FlyinMiataVideo]

Since it's a recirculation type, it doesn't make much noise and more like an OE build.

[@baltod4978]

@FlyinMiataVideo Sorry! I meant on both recirculating and open to atmosphere. One of the first things I did was replace the bov with a greddy type s- JUST to hear something! Especially with as much money that I'd spent on the kit. Though I now know I have to replace the stock ecu with a stand alone and delete the maf- it'd of saved me time and money to know what my turbo smart would've sounded like open

[@JohnKowalskyDrive]

Thank you for the information! So it doesn't make any sense to run a atmospheric valve on a stock turbo Mazda 3 for example. I noticed that throttle response is a bit more on and off when it's open valve and the engine is moving around more.

[@FlyinMiataVideo]

@JohnKowalskyDrive You are welcome! You wouldn't want to run a vent-to-atmosphere BOV on a car that is still using the MAF sensor - it would essentially act as a large vacuum leak, which will cause the check engine light to come on. Additionally, you would likely experience some drivability issues as a result.

[@JohnKowalskyDrive]

@@FlyinMiataVideo Can this eventually lead to a lean A/F ratio?

[@FlyinMiataVideo]

@@JohnKowalskyDrive Yes; a vacuum leak will cause a lean A/F ratio.

[@scottr3141]

Why doesn't FM sell the Voodoo box separate anymore, and the stage one kit is never available ?

[@FlyinMiataVideo]

Our Voodoo box fuel controller is considered to be an emissions defeat device, meaning we cannot sell it without a CARB-EO. This means they can only be sold with complete turbo kits, as the complete kit has a valid CARB-EO. We aim to have more NA/NB turbo kits ready to ship around mid-October, and appreciate your patience!

[@nolahahnshouse3389]

This is one I know about but at the same time I don’t

[@FlyinMiataVideo]

This video is pretty basic level stuff, but good knowledge for anyone thinking about a turbo kit!

[@christophermeraz-mata]

Which is better for reducing lag, BOV or Recirculate? Can the Recirculate line end up in the exhaust manifold instead of in the intake?

[@FlyinMiataVideo]

As long as you have a well designed turbo system, we haven't noticed much difference in performance between the two. Now, noise is another thing. The recirc hose from the BOV will need to enter the intake track after the MAF if it's used. If you're not running a MAF, it can go wherever you want.

[@twrcrew8852]

Does anyone make a remote oil filter kit for the ND? It's just something I do to all my cars and this is the first time I couldn't. (Also a huge bummer that there's a baffle in the dipstick tube, so my vacuum pump - another thing I love and use for all my cars - doesn't work there either. lame! My body doesn't like being scratched up crawling around on the floor due to the medication I have to take, so I've made my life easier where I'm allowed to) It always feels as though the ND is being left in the dark as far as aftermarket engine support, power mods and in general for everything else? I can't find anything beyond basic bolt ons and OFTs. It's just a sad state we are in where the oldest floppiest miatas can be 400whp semi analogue monsters while those of us who took a chance on the new ones might never see the full potential of all this advanced technology and extra rigidity within the context of monster boost.

[@travdripdrip382]

Wait a minute..... Did he say the FM turbo kits work with stock ECUs????

[@muaddib2678]

FM Guys chime in here if I get this wrong... Yes the stage one kit works with the stock ECU using what FM refers to as their Voodoo Box. Here this is from their website on the kit: Fuel management is handled by our own Voodoo Box, which uses the stock injectors to deliver more fuel. Because it only modifies the signal under boost, the car acts completely stock at idle and cruise. There is no tuning required.

[@FlyinMiataVideo]

Thanks, good explanation!

[@FlyinMiataVideo]

Our FM Turbo kits use our Voodoo Box to connect to the stock ECU for fuel management to keep our kits 50-state-legal, with no aftermarket ECU or tuning required.

[@c34laurel]

Bov before or after IACV ?

[@FlyinMiataVideo]

You'll want the BOV piped to the intake piping and before the TB.

[@c34laurel]

Yes the bov before the tb. What about the IACV. Should I plumb it before or after the bov.

[@FlyinMiataVideo]

@@c34laurel We might be misunderstanding your question. The Idle valve on the Miata is either attached to or a part of the throttle body, depending on what year you're working with. Are you talking about your boost reference line?

[@c34laurel]

@@FlyinMiataVideo normally the IACV is attached to the intake manifold and the hose to pre TB. My question is, that hose pre TB, should it be before or after the BOV inline.

[@FlyinMiataVideo]

@@c34laurel Thanks for clarifying. The placement of the BOV in relation to your IACV doesn't matter.

[@user-im6hd8qh5y]

Does anyone know much about the 2000 wrx bugeye need some advice if anyone can help. thanks😁

[@FlyinMiataVideo]

Sorry man. Miata is our game here.