Adam Poland

I have lindsey racings billet BOV on my car currently. I wanted an atmospheric BOV, however, I've heard that atmospheric BOVs are not good for 951s? Is this true?

alxdgr8

You need to run a blow-thru MAF setup if you want to run an atmospheric BOV. Otherwise you will be dumping metered air and it will run rich in between shifts. They make some partial dump diverter valves (dump a portion to atmosphere and recirculate the rest) that will make the car run not so rich but still give a louder atmospheric sound.

Darwantae951

There really isn't any gain by going this route. Are you doing so to attain the sound?

VOoDOoGTX

HKS makes a recirculated BOV but be prepared too spend 400+ on that.. Otherwise go buy a honda.... and turbo it.

hp18racer

The AOS in the 944 works very poorly. If you do an atmospheric blow off valve it will puke oil, makes a big mess.

Cory9584

I vent to the atmosphere and don't experience any negative effects. The car still feels normal between shifts and there's no oil spewing from it. I'm not a ricer and it's like that only because my intake pipe has no provision for a diverter and i dont want to waste my time and money having it welded since i'm going with an ems possibly over the winter anyway.

spoolin51

Do you have standalone?

hinch951

I have one of the "evo" style diverter valves, similar to the stock set up and everytime I go to shift into second or any other gear the car bucks and jumps until the rpms climb a bit. It has never run right since I installed it. However, the stock BOV runs fine, but I can hear it flutter in between shifts, i am assuming a bit of compressor surge. I also have one of the older style lindsey racing bov's and it reacts the same as this "billet" style with the solid piston. Some guywho works on audi tt's said you have to oil the hell out of them,because the piston sometimes sticks....I wasn't sure if I neededa different spring or what? I am running a autothority MAF setup, with chips and that's it. Stock k26.

badcoupe

I have a tial and changed my vitesse over to a blowthru when I fabbed my front mount IC up. To vent to atmosphere you need to go blowthru or speedensity other while they typically run bad between shifts, sometime blow a flame or two out the exhaust.

944obscene

My stock car pops flames out of the exhaust. Fine by me. I'm running ALL stock equipment, save the LR 3" exhaust. Even with the stock exhaust, I'd pop a 7" flame out the back sometimes.

Adam Poland

Same here lol. But I was not going for this to attain the sound. I was hoping maybe I could just maybe clean things up a little bit by removing the vacuum line. I just heard this and wanted to see if it was true or not. Im not wasting money on one if I already have LRs billet BOV. It was just curiosity.

mclarenno9

This.

Trust me it sucks big time.

Darwantae951

Mine works find and I have very little oil in my intercooler/intercooler pipes/intake manifold. If you're having issues with excess oil it may be from worn rings or scored cylinders allowing excess blow-by and pressurizing the crankcase, forcing oil vapor thru the AOS and into your intake system.

mclarenno9

I understand my rings are probably not in the best condition and I probably get a bit more blowby then most, however it is my understanding that a bit of oil in the IC pipes is "normal" for these cars. Some of it could be coming from that pesky little K26 you see in my avatar!

I had one for a week and it sprayed a mist of oil onto the foam under-hood insulation and made a mess, so I got rid of it. Now I have a MAF so I have the best of both worlds. I can hear the recirc valve quite well.

Darwantae951

Yep, oil is considered "normal" because the design of the crank case ventilation system is a closed system. It's also a small plus to pull a vacuum on the crankcase (altho I don't know exactly how much, if any, the factory AOS pulls). If you want to reduce the oil, one way is to get an Oil catch can. Several options are out there for that.

I decided to go with a blow-off valve for two reasons. 1) the intake pipe I bought (no MAF for me, I'll be using MAP) did not have the provision for a bypass valve, and 2) I didn't want to run into any restriction problems as far as releasing pressure. I will be running 15psi normally but 20psi occasionally.