Why does anyone throw away hp with a blow off valve?
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Joined: Jul 2004
Posts: 75
From: Indianapolis,Indiana the arm pit of of the average white guy.
Car Info: Dont ask me why I throw it side ways and yes am mad when I drive.
Where's the love for this guy
Originally Posted by Roberto
I know some of you don't want this to turn into a tech discussion, but it's a comment that is in dire need of a technical answer.
Many if not most stock diverter valves will leak at higher boost pressures. This has been tested many times by myself and others. If a valve starts to leak at say 19 psi, and your target boost is 24 psi, you'll be running the turbo harder that it should to obtain 24 psi at the intake manifold. As the compressor head psi goes up, the compressor discharge temperature goes up, creating more heat for the intercooler to relieve (which it cannot), and ultimately creating a higher intake temperature, and making less horsepower.
If you are running less boost than the stock diverter valve will leak at, then switching to an aftermarket blowoff valve will be nothing more than a noise maker. However, if you are running boost above the leak-point of the diverter valve, then you have a boost leak that is costing you horsepower via higher intake charge temperatures. In that case, switching to a properly configures blowoff/diverter valve will be like picking up a bit of intercooler efficiency, and you'll be working the turbo a little easier for the same intake psi.
Many if not most stock diverter valves will leak at higher boost pressures. This has been tested many times by myself and others. If a valve starts to leak at say 19 psi, and your target boost is 24 psi, you'll be running the turbo harder that it should to obtain 24 psi at the intake manifold. As the compressor head psi goes up, the compressor discharge temperature goes up, creating more heat for the intercooler to relieve (which it cannot), and ultimately creating a higher intake temperature, and making less horsepower.
If you are running less boost than the stock diverter valve will leak at, then switching to an aftermarket blowoff valve will be nothing more than a noise maker. However, if you are running boost above the leak-point of the diverter valve, then you have a boost leak that is costing you horsepower via higher intake charge temperatures. In that case, switching to a properly configures blowoff/diverter valve will be like picking up a bit of intercooler efficiency, and you'll be working the turbo a little easier for the same intake psi.
Some one needs to give this man props. I'll be the first. So go head and keep trying to pick up girls with some little pissing noise while the rest of us take you out at the track ok. You know if she sleeps with you for your car noise your probably going to need a rubber. See you at the tracks guys.
Late
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From: on da compz...readin' yo blogz
Car Info: "the loud one"
Originally Posted by poser
if i was a chick, i'd get wet hearing it... 
and it reminds me of my race and culture (i'm 100% filipino)....pssssssssshhhhhhhttttt
and it reminds me of my race and culture (i'm 100% filipino)....pssssssssshhhhhhhttttt
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From: El Cerrito, CA
Car Info: 2014 Mazda MX-5 GT PRHT
If I was a girl, I would own stocks in Victoria Secret and Fredricks of Hollywood (cuz I'm a freak nasty hoe.) because if I heard the "pssssssssssshhhhhhhh" I'd only have crusty-patis smellin panties left in my room... ohh.. and I'd lick and suck on my own nipples while a WRX with a BOV drove by my room giving that innocent school girl look and having a sailormoon outfit on too. 
Token Toyota Mod
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From: Palo Alto, CA
Car Info: Something german
Originally Posted by sireatalot
If I was a girl, I would own stocks in Victoria Secret and Fredricks of Hollywood (cuz I'm a freak nasty hoe.) because if I heard the "pssssssssssshhhhhhhh" I'd only have crusty-patis smellin panties left in my room... ohh.. and I'd lick and suck on my own nipples while a WRX with a BOV drove by my room giving that innocent school girl look and having a sailormoon outfit on too.
Originally Posted by sireatalot
If I was a girl, I would own stocks in Victoria Secret and Fredricks of Hollywood (cuz I'm a freak nasty hoe.) because if I heard the "pssssssssssshhhhhhhh" I'd only have crusty-patis smellin panties left in my room... ohh.. and I'd lick and suck on my own nipples while a WRX with a BOV drove by my room giving that innocent school girl look and having a sailormoon outfit on too.
Originally Posted by RAGE
I run the type-h on my car...
I only bought it because the stock on started to leak at 18psi... I run around 19 to 19.5 peak boost. When I first put it on the car it didn't seem to run right, but after I put in the correct number of spacers it works great. It holds boost and I peak at 19 (give or take a little) and hold 17psi to redline. If I wouldn't have needed to buy one, I wouldn't have... I personally don't like the attention that it can bring to the car. Not that my yellow car doesn't catch anyones eyes anyway...
I only bought it because the stock on started to leak at 18psi... I run around 19 to 19.5 peak boost. When I first put it on the car it didn't seem to run right, but after I put in the correct number of spacers it works great. It holds boost and I peak at 19 (give or take a little) and hold 17psi to redline. If I wouldn't have needed to buy one, I wouldn't have... I personally don't like the attention that it can bring to the car. Not that my yellow car doesn't catch anyones eyes anyway...
*** at me with your BOV... hehe
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Car Info: 2014 Mazda MX-5 GT PRHT
sorry,.. when I move up to O'ahu in a few years.. I'll be on Kuhio sellin my body for span masubi and pork cutlets.... and when I hear a WRX with the BOV.. I might pop a gasket
note: I'll be standing in front of the **** shop with the old grandma and grandpa that own that place on Kalikawa
note: I'll be standing in front of the **** shop with the old grandma and grandpa that own that place on Kalikawa
LOL...I just screwed up my GFB Hybrid when I was cleaning and lube'in it! I stripped one of the screws and can't get it to tighten...had to go back to stock 
Oh well, as a hybrid I was getting a little of both worlds but the sound just wasn't that loud and went WOOOSH when I wanted Pssshhhh! Gonna hit Sears today and get some stuff to solve my little f up!
Oh well, as a hybrid I was getting a little of both worlds but the sound just wasn't that loud and went WOOOSH when I wanted Pssshhhh! Gonna hit Sears today and get some stuff to solve my little f up!
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