evoseller888

hi i tried searching about this but couldnt really find a thread that hit the nail on the head. i am a noob at this so forgive my question about this if it seems dumb. i have heard bov's fluttering on cars and read from other threads on here that the fluttering is bad. Why is it bad for evos when other cars do it? And would it be possible to do it with our cars and if so what bov would do this? Also i have heard that the fluttering is the wastegate on turbo setups that have aftermarket turbos with external wastegates. any and all information and tech would be greatly appreciated. thanks for looking everyone.

justa4banger

iTrader: (14)

if its excisive flutter to the point that its compressor surge it bad....because the air stalls the compressor.....

GPTourer

A fluttering BOV usually means the adjustment screw on the diaphram is on too tight and the valve is not opening properly under boost. Even with a properly setup valve, a BOV might still flutter under part throttle, light load and low boost situations. Still, it can be fixed depending on how the ports are used.

Fluttering on a wastegate is different. An open dump might have a lot fluttering or "chugga-chugga" sound under full boost as the wastegate is regulating boost, but that's normal.

Evoardo IX

iTrader: (21)

I don't think fluttering are bad for evos particullary, it's vent to atmosphere valves that evos do not like, because of the MAF sensor and air/fuel metering. Comprssor surge is bad, shortens the life of turbos, but I even heard of people running with reversed DV or even no DV at all, so I don't know for sure. But to answer your question, if you want the wooosh sound, you can run your evo with no airbox lid, or get a vent to atmosphere valve as long as you are tuned for it or run a setup with no maf. Hope that helps, my advice, don't alter the fuel/air in the car if you don't get a tune.
Ed

max4rw

iTrader: (8)

do it the right way and just get an open air intake system and a Ix dv you will love the sound trust me and have good drivability, you might have to get a tune to make it run right depending on witch intake system you get!

evoseller888

thanks for all the information so far guys. i seem to hear 2 types of fluttering sounds, one which is a pure air sound type flutter where it sounds like all air that is fluttering while the other is a high pitched flutter. i saw a dyno video of a wrx with arc bov have that high pitched fluttering sound; when the throttle let go it made the sound. and the owner of the car said that it was normal to sound like that after i had asked him how come it sounds so crazy. any input on this guys? thanks.

Raceghost

iTrader: (4)

what about lube with a BOV. I noticed my forge had some type of grease in there. Now I didnt think to add any, because it was a light coating. Should I add some for proper use? It sounds like the one I have might be sticking... Can this cause that type of surge you are suggesting?

xDJ_Aeonx

iTrader: (1)

well i didnt want to start a new thread so what i was wondering is if fluttering ocassionaly is bad? i usually dont flutter unless im running on lower rpms/only slightly spooling up the turbo...it usually happens when i only hit about the 2 psi range. Other than that, it always just releases the air in one shot. Like i said, it only flutters when im shifting a little lower, so it is that bad or should i just stop shifing so low? lol sry, im a newbie.

AznDragonV

iTrader: (14)

^^ no its fine .. mine does that. i have a forge rs

as long as it doesnt flutter at high boost and or high rpm

churbo

iTrader: (2)

^^x2 beat me to it.

JDMevoBOOST

iTrader: (37)

I would say that a little bov flutter when letting off on low rpm low boost is pretty normal for me in traffic. Now if you are giving it considerable amount of gas and accelerating and you get a fluttering noise, then you might have reason for concern.

EVOSan

iTrader: (2)

same here, i have a forge rs and it flutters under part throttle, but as soon as i go WOT it holds just fine

05EvoVIII

iTrader: (2)

i have the agency power bov and it flutters when i build like 10psi and let off...what should i do tighten or loosen the screw?

AznDragonV

iTrader: (14)

if it flutters try loosening it all the way and tighten a little at a time until the point where there is no flutter.

but like i said earlier in this thread... low rpm and low boost flutter is usually ok.. USUALLY

jxs1984

iTrader: (17)

what if its an ix bov and it flutters at full throttle? what would be the problem?