BOV tuning questions
#1
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BOV tuning questions
So running the GFB valve from FM and got the car driving again. Valve is VTA with a K&N filter on it. The Vacuum hose doesn't share with anything and is connected under the thottlebody. At idle the valve is open, ya. Going into boost swear I can hear the thing close. How do I describe this......Driving in cruise and smash the throttle down. The intake makes a noticable change in suction sound just after the gauge sweeps past 0psi. Almost like I can hear the motor trying to suck air in at the BOV and then transition over to the turbo intake. This normal? Never remember hearing this on my SR powered 240 running a greddy valve.
On top of this is I can hear the turbo "chirp"/"shudder"/"surge" just a little. Just 2-3 little chirps. Not after a higher boost let off (4psi plus ish) or just shifting in traffic. Only when I lightly pass someone. Like a quick throttle to 0psi ish then let off cause the dick cuts me off.
I know I can adjust the preload on the valve. Question is how do I know what is too soft and opening under boost? If I go too hard on preload it'll surge all the time probably/not react fast enough. Change intake mani fitting location? Also don't have an air compressor or pressure hand pump yet either. Really the surging sound just translates to turbo abuse in my head.
On top of this is I can hear the turbo "chirp"/"shudder"/"surge" just a little. Just 2-3 little chirps. Not after a higher boost let off (4psi plus ish) or just shifting in traffic. Only when I lightly pass someone. Like a quick throttle to 0psi ish then let off cause the dick cuts me off.
I know I can adjust the preload on the valve. Question is how do I know what is too soft and opening under boost? If I go too hard on preload it'll surge all the time probably/not react fast enough. Change intake mani fitting location? Also don't have an air compressor or pressure hand pump yet either. Really the surging sound just translates to turbo abuse in my head.
#2
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The surging sound won't hurt anything, and if you are getting that sound, it means the valve is closed. It almost sounds like the valve is moving slowly and needs to be lubed or broken in.
#3
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Yeah the valve just seems laggy. I did tear it completely apart, clean it, and lube it with some killer gun oil. I use the same stuff on my Glock and should be safe for the little teflon seal in it. Very little amount used FYI. I've been fixing little stuff from the previous owner. He never had the BOV even hooked to vac for a couple years
Any recommendations on a good vent to atmo BOV? The Forge valve seams to have disappeared online and I am not paying over $150 for a valve or buying knock off china stuff. Unless someone can vouch something specific.
Any recommendations on a good vent to atmo BOV? The Forge valve seams to have disappeared online and I am not paying over $150 for a valve or buying knock off china stuff. Unless someone can vouch something specific.
#8
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Problem fixed.. ish. Little adjustment was needed. More curious on how to test if the BOV is adjusted to light and leaking under boost. More specifically how to test it without an air compressor.
Edit: Little interested in triple88's valve though
Edit: Little interested in triple88's valve though
#10
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Once I put the right spring in there, I've never looked back.
Calling off-throttle chirpy BOV "surge" is like calling Steve Urkel a "power lifter". If there is no fiery pressure in the turbine, it's not "surge". Engineers may feel free to correct me, but I've running a fairly stiff spring in my BOV, have been for 3-years, and my turbonator looks fine with no play. Run a stiff enough spring to keep the valve closed in overrun, you should not hear the BOV open in vacuum.
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