cheap bosch bov replacement
#21
Boost Pope
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Since we are measuring pressure after the turbo but before the engine, flow through the engine will be the same for any given pressure, regardless of how the pressure got there. Doesn't matter it was from a TD04, a Roots blower, or six thousand Moroccan women blowing through a straw.
#22
There are two things being discussed here. The "amount of air" that we care about for making power, the number of O2 molecules entering the engine, is not completely dependent on pressure, but rather pressure, volumetric flow rate, and temperature. The bov, however, only cares about pressure, and couldn't care less about temperature, flow rate, etc.
#24
Pressure was accounted for.
Air temp was somewhat accounted for by the compressor efficiency statement. More would play into it but I figured my simplified explanation would be enough to discount the much regurgitated misinformation that a big turbo flows more at a given pressure than a small one.
#30
Ben, Given the FIXED consumption of air the engine is using (proportionate to rpm) 15 psi is 15 psi. A larger turbo doesn't have to flow any more or less cfm to make 15psi on a Miata or any car. For example if an NA motor draws 250cfm then pumping 500cfm into it would make 14.5lbs of boost. Not counting VE of the engine or any of that. Any gains at all might be from a larger turbine having less resistance in the exhaust. Think about it like a bucket. The level of water in the bucket is the pressure and there's a hole in the bottom representing your engine's consumption. The amount of water required to fill the bucket depends on the size of the hole. Not the pump filling the bucket.
m2cupcar, where's the sound samples?
m2cupcar, where's the sound samples?
#33
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ima get one too i think, Ive finally started upping the boost on a cheapo diy boost controller to ~11 psi now, but it spiked to 15 a few times so im gonna chill here, but i dont wanna loose any efficency or spool on my 2554
#34
Former Vendor
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To answer the question on will a Bosch hold XXpsi on XX turbo - I am pretty sure I lost my BOV after the equivalent of four track days this weekend (two drivers, two days). It used to make a very clean woosh when I lifted off above 0psi, but now it makes a quieter hiss when I lift at low pressures, and the clean woosh followed by a quieter hiss at higher pressures. I haven't had time to get it off of there yet, but I'll be looking into an all-metal replacement.
My setup is a T25 at 13psi, poorly tuned at 200rwhp.
My setup is a T25 at 13psi, poorly tuned at 200rwhp.
#39
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Two things:
1. My Bosch valve was fine. The noise changed because the check valve cemented to the end of the BOV gutted itself a few weeks at Buttonwillow.
2. The new metal BOV is very nice, quieter than the Bosch, and a direct replacement.
Anyone want to buy a Bosch? I have two.
1. My Bosch valve was fine. The noise changed because the check valve cemented to the end of the BOV gutted itself a few weeks at Buttonwillow.
2. The new metal BOV is very nice, quieter than the Bosch, and a direct replacement.
Anyone want to buy a Bosch? I have two.
#40
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As promised, here's some vid of the acceleration for the bov sound. No silly noises, just a good release of boost - just the way I like it.
Yes, that was "unmarked" crown vic in the second vid.
Photobucket's video encoding sucks! First vid gets the idea across, but the second one is almost useless. Maybe I can encode the flv files myself and pbucket will leave them alone?
Yes, that was "unmarked" crown vic in the second vid.
Photobucket's video encoding sucks! First vid gets the idea across, but the second one is almost useless. Maybe I can encode the flv files myself and pbucket will leave them alone?