Saturday, September 29, 2007 - 08:35 am, by: Dale Holan(Xtrax)
I have an aftermarket HKS Super Blow Off Valve something doesn't seem to be running right in my mind. What RPM/boost level should my BOV blow off? Can it be adjusted? It sounds like I'm getting a compressor surge at lower RPMS (3000 to say 4500) but It'll blow when I'm well over 5000. Also I'm unsure if It is hooked up correctly. It seems to have 2 lines going in but they come from the same source.
Saturday, September 29, 2007 - 09:15 am, by: Grant Rowan(Booster13psi)
I have a HKS SSQ Bov. I have noticed that it blows audibly at about 5psi and above. The SSQ should have an adjustment nut on the back of it. I have never touched mine so I don't know what adjustment increments can be made.
Sunday, September 30, 2007 - 03:25 am, by: Dale Holan(Xtrax)
I'm not too sure if mine has an adjustment screw or how to adjust the tension spring. I'll take a couple photos, maybe you can suggest how to adjust it. thanks for your help.
Sunday, September 30, 2007 - 06:17 pm, by: Scotty Wheeler(Typhus_sw)
my guess would be that you still have your factory plumb back, which is found at the end of your plenum, which is the same as a bov only when it opens it lets the pressure out of the plenum and is plumbed back in just after your air filter. Hence the flutter daniel is talking about is the air from the plumb back flowing out your air filter. Your bov won't be as audible because the majority of your air pressure is goin through your plumb back, if you adjust your bov so the spring is softer it will be more audible.. Probably help more if i could explain it a bit better but thats the best i can do for now, Good luck with it.
Sunday, September 30, 2007 - 09:30 pm, by: Charlie Ters(Ul05st)
what he means is that at around 0psi, his blow off valve isnt going WOOSSHH loudly .... (maybe very lowly)...well the truth is, no blow of valve does, nissans for example, will always have major fluttering under 6psi, and BOV's are made to vent EXCESS psi..... anything under 'excess' (which is mostly spring related) will not open a bov.... simple, remember your HKS blow off valve is made to probably support 600hp++, you cant expect around 300hp to let it off at its full potential using ct-12's @ 0-6 psi @ 2900rpm etc.... well... thats my theory if a BOV doesnt open at 7psi+....then something is wrong (but remember with the the soarers, it aint open for too long)....
Wednesday, October 03, 2007 - 09:18 pm, by: Steven Anderson(Cusscuss)
Had to think through this one a couple of times.
BOV's use springs in them to keep them closed when idle and under boost as there is equal pressure on both sides.
It when there is a pressure difference ie, throttle closed and vacuum in the plenum but boost in the pipes it will force it open.
Sometimes vacuum is not enough to overcome the spring e.g. low revs so the BOV will not open. This is why some of them have adjustable springs in them. Its normal behavior.