Turbo Surging???
Jul 25, 2007 | 12:06 PM
#11
GFYS and STFU
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From: Here and sometimes there too.
Originally Posted by WJ MARK
My blow off valve sounds like a rattle snake when I let off the gas. Im pretty sure that is normal though.
Same here. This is mine, you can hear it at 105 when I let off the gas...
http://www.youtube.com/watch?v=ukXiYmwaEw4
Jul 25, 2007 | 12:44 PM
#12
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Originally Posted by WJ MARK
My blow off valve sounds like a rattle snake when I let off the gas. Im pretty sure that is normal though.
Jul 25, 2007 | 01:23 PM
#13
Originally Posted by Turbo 6.0
It sounds like your BOV isn't even opening because that is the sound of compressor surge. how many lbs is your BOV spring?
Jul 25, 2007 | 02:05 PM
#15
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From: colorado above 6000 ft.
Originally Posted by Turbo 6.0
It sounds like your BOV isn't even opening because that is the sound of compressor surge. how many lbs is your BOV spring?
That wasn't my vid.
Mine makes the rattle snake sound when I build alot of boost fast then get out of it real fast. When I build boost aliitle slower and then let out slower it makes the phhsst sound. I have a turbosmart dual port blow off valve that is adjustable hard and soft . I definatley don't feel any surging though.
Jul 25, 2007 | 03:14 PM
#16
GFYS and STFU
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From: Here and sometimes there too.
Originally Posted by WJ MARK
...Mine makes the rattle snake sound when I build alot of boost fast then get out of it real fast. When I build boost aliitle slower and then let out slower it makes the phhsst sound. I have a turbosmart dual port blow off valve that is adjustable hard and soft . I definatley don't feel any surging though.
Also you can't "feel" the turbo surge the mass of the turbine wheel is far too small to shudder or vibrate our trucks.
Jul 25, 2007 | 03:54 PM
#17
Originally Posted by Spoolin
Ok, kool, that's what I figured. I can see how it's not as important at 6 psi but I'm wondering, is Slowhawk using his truck on the street? At a track I can see how it isn't all that important since with the auto the shift are so quick and after your pull your not getting back on it right away. On the street you loose alot of spool time I would imagine and add a little lag time with the nature of street driving.
Anyways, I guess Noonie is safe for now. Too bad STS doesn't chatter up on the forums, could tell us why a BOV doesn't come with all kits.
I'll ask turbo 6.0, maybe he can tell us.
Anyways, I guess Noonie is safe for now. Too bad STS doesn't chatter up on the forums, could tell us why a BOV doesn't come with all kits.
I'll ask turbo 6.0, maybe he can tell us.
Slowhawk's quote was on his GN I think. I believe he said it was a street driven vehicle.
Again, if you get out of boost slowly, you get no noticable surge. It's just when you nail it, get into some boost and jump off the go pedal. For a manual, you do that during shifts, and the turbo wheel is slowed down drastically by the surge, meaning you have to spool up again in the next gear. For that situation a BOV is definitely beneficial -- keep your wheel moving at speed, no need to spool up again. For an automatic, you don't lift, which means the throttle stays open and no surge occurs during shifts.
As far as harming the turbo, Jose may be correct -- this surge you get with automatics may decrease the life of the seals, etc., but the question is: how much? Is it worth worrying about? I think there is enough evidence to the contrary for the everyday driver. People have been running automatics sans BOVs in low boost applications for decades. High boost? I'd have a BOV (or TWO!
)STS doesn't include BOVs in automatic cars because their base kit is set up for 5-7psi (not to speak for STS but I've been friends with Rick and Dave for a long time now and asked them this very question years ago). When you start talking to them about big boost, they recommend a BOV to protect the turbo.
, but my **** seems to be working fine. 
