Don't run one right now on S/c boat or my turbo sled. Are guy finding any real advantage when running under 10 lbs boost?
BOV'S the good bad and the ugly.
- Thread starter allblowdup
- Start date
I apologize in advance for the noobie question, but what would the reasoning be behind having one at high boost? And why wouldn't it apply at a lower boost?
M
mike_s
Well-known member
A blow off valve, or compressor bypass valve, is never a bad idea on an air throttled engine. When the throttle slaps shut all that airflow has no place to go and it forces its way back out the compressor, causing compressor stall or "surge", this can actually stop all motion of the turbo and in rare cases cause the shaft to reverse. This causes some pretty insane loads on things, erodes compressor blades, destroys turboshaft bearings and thrust bearings. I have seen compressor surge actually wind the compressor nut off the turboshaft before. When given a choice, ALWAYS run a BOV.
plus rumour has it having a blow off valve allows you to spool it back up quicker after a full throttle cut from wide open
M
modsledr
Well-known member
This is basically true...by bleeding off the back pressure through the BOV, the turbo remains spooled up, therefore reducing the "lag" in on/off/on throttle situations.
BOV's
I've posted this before. Pick your poison.
http://www.siliconeintakes.com/stpg.php?page_id=bov
I've posted this before. Pick your poison.
http://www.siliconeintakes.com/stpg.php?page_id=bov
HAving a BOV for high boost applications is more important. The compressor spins faster and the loads on it are higher so when the throttle is chopped the surge and loads are much higher. The rule of thumb has been that less than 10 psi a BOV is not needed.
My question was that even if it is not needed is there an advantage to having one. It does seem so!
