I just installed new intercooler piping and a new HKS SSQ BOV. The BOV flutters bad. I backed the screw out all of the way but that dose not help. Anybody else have this problem? I don't want to damage my turbo with compressor surge.

Well, there have been several fixes that I have heard. Have you tried the vacuum signal? I also heard turning it around, but I'm going to imagine low boost it flutters and probably sounds fine above 8-10 psi. Most BOVs are thought to go in cars that run higher boost stock than Stage I or II's. These are just some thoughts.

I have an RFL and if I barely give it gas and boost builds to anything under 4psi, it flutters 4 times out of 10. Anything above that is fine (and loud I might add)

Yeah. It flutters at low boost. I get a loud squeal at 10 to 12psi then about 5 or 6 fluttlers as the boost drops.

I have the Blitz Supersound. It would flutter bad with partial boost or full boost (8psi). I took it apart and cut one coil off the spring. Now the only time it flutters is at 1-2psi, and it still holds boost fine up to 13psi so far.

I had the same prob with my GReddy Type-S..then I took out one of the springs and my BOV sounds a nice hi-pitched whistle at or near minimal boost. It's getting annoying now..i want a new sound like the HKS standard

Alvin

96 RST

Star Stage I turbo kit /Starion I/C w/ 2" chrome piping / GReddy Type-S BOV / Missing Link / Custom APEXi- GReddy 2.5" exhaust / 55mm ARD TB/ Nology wires / APEXi EL mech boost gauge / Autometer A/F gauge / Southland Dual Friction clutch / B&M short shifter / Energy Suspension shifter bushings / 16" GSX Rims / Front/ Rear camberkits / Eibach Prokits / Tokico Blues/ Front Upper, Rear Lower strut bars / Rear GST sway bar
GSX Dual Piston Calipers, X-drilled rotors /

BOV flutter isn't bad. At low boost levels you don't even need a BOV. I hear a lotta turbo cars flutter. Haha I know it doesn't sound cool though. When I installed my starion intercooler mine started fluttering.

ummm... last I knew, that fluttering is compressor surge. Which IS bad.




-Tony '98-GST
eclipzgst@charter.net
http://eclipzgst.webhop.net
turboclipz on AIM

That is what is is. I can hear it surge out of the intake on the turbo. I called HKS and tried to explain it to him. I don't think he understood what I was trying to tell him. They told me that is characteristic of the SSQ.

Yeah I have the blitz dd bov and mine does the same thing. It flutters under very low boost and makes a strange tooting squeeling noise at about 7-8psi. A guy told me to just tighten down the screw but it is almost down all the way and no imprvement. I called blitz and they were no help. It sounds so dumb that I am embarresed when it does it to the point that I want a diff one.
Patrick
96 GS
HRC kit, S20G, FMIC, Howell bottom end 8.6 pistons, S-FMU, Blitz BOV, P&P head, SS valves, lots more little goodies

I think with most aftermarket BOV's you're gonna get some fluttering. The springs are strong so they can hold high amounts of pressure, but low pressure isn't enough to open the flapper constantly, so it flutters. A lot of the 4g63 guys have this problem too when they try to vent to atmosphere instead of recirculate.

I'd say loosen the spring as much as possible to make it easier to open, but make sure it will still hold your max boost. If it's still fluttering at full boost, I suggest taking the spring out and cutting a little bit off. Fluttering with low boost is very common, but it's not really harmful to your turbo with such low pressure. If you're getting fluttering at full boost, your BOV isn't opening enough to vent the pressure and it's trying to spin you turbine wheel backwards, which can eventually damage your turbo.

I desided to back the waste gate off a little bit and control boost with my manual boost controler a little more. I was hoping that the waste gate would open at 0 throttle a little better. Putting less force on the turbine. I have managed to get it to the point that is only flutters at low boost, but it is pretty gay sounding. Sounds like an owl hooting under my hood.