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Old 09-07-2003, 01:56 AM
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I'm gonna sound dumb here, but what exactly is a wastegate. And how do you know what size your car needs. I've been wondering this for a long time and any help wuold be greatly appreciated.
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Old 09-07-2003, 02:18 AM
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Wastegate...simple. It an "opening" thats used to exit excess exhaust gas. The more exhaust gas that goes thru the turbo, the more it will spin and cause more boost. You need the wastegate to interrupt that exhaust gas BEFORE it gets to the turbo. All that excess exhaust gas could be considered "waste" since it is not needed, and "gate" is essentially what it is. As soon as the required boost level is achieved, the "wastegate" opens up and dumps the extra exhaust gas out.



get it?
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Old 09-07-2003, 03:25 PM
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Ok, but how does that help reduce boost creep? Like having a bigger one.
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Old 09-08-2003, 06:47 AM
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Well...think of it like this. Exhaust gas has two ways of escaping...towards the wastegate or towards the turbo. Towards the turbo builds boost. If you overload the wastegate(small one that can't handle all the exhaust pressure), the exhaust gas will go to the other way of escaping, the turbo...now remember what I said about how you build boost? more exhaust gas makes more boost. If you overload the wastegate and send all the backpressure towards the turbo, you'll cause it to spool more, which will increase boost....or boost creep.
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Old 09-08-2003, 12:29 PM
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And the size of the wastegate isn't all that important, as long as it's quite a bit more than large enough to handle any sort of boost creep. Then you just tune your boost controller to raise the boost to the level that you want.



Oh, and the stock wastegate is large enough for a stock car. You'll know you need a bigger wastegate when you start modding and making more boost than you ought to be.
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Old 09-08-2003, 12:53 PM
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What is the difference between a wastegate a BOV?
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Old 09-08-2003, 03:07 PM
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BOV is for releasing gas after the throttle body closes and before it reaches the turbo.



When you let off the accelerator the throttle body shuts or closes, leaving the pressurized intake nowhere to go but back the way it came (turbo) causing backpressure and putting un-needed wear on the turbo. A BOV releases the Intake charge before it reaches the turbo thus reducing back pressure and reducing turbo lag.







Basically a wastegate deals with handling exhaust gases while a BOV handles Intake Charge.
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Old 09-08-2003, 05:58 PM
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Originally Posted by ZenRXSeven' date='Sep 9 2003, 02:29 AM
And the size of the wastegate isn't all that important, as long as it's quite a bit more than large enough to handle any sort of boost creep. Then you just tune your boost controller to raise the boost to the level that you want.



Oh, and the stock wastegate is large enough for a stock car. You'll know you need a bigger wastegate when you start modding and making more boost than you ought to be.
No. Wastegate size is VERY important. You don't want to boost 1.0 kilos on a T-04E with a stock fuel system...that's close to the border of fuel starvation. I've seen this happen because the wastegate was too small. If the owner had just bought a larger wastegate, instead of an "adequate" one he wouldn't have been in this predicament.



Size the wastegate so that you can run the LOWEST amount of boost possible. Then use your boost controller to turn boost up.
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Old 09-08-2003, 09:32 PM
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What exactly is boost creep?
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Old 09-08-2003, 09:43 PM
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Originally Posted by jspecracer7' date='Sep 8 2003, 02:58 PM
[quote name='ZenRXSeven' date='Sep 9 2003, 02:29 AM'] And the size of the wastegate isn't all that important, as long as it's quite a bit more than large enough to handle any sort of boost creep. Then you just tune your boost controller to raise the boost to the level that you want.



Oh, and the stock wastegate is large enough for a stock car. You'll know you need a bigger wastegate when you start modding and making more boost than you ought to be.
No. Wastegate size is VERY important. You don't want to boost 1.0 kilos on a T-04E with a stock fuel system...that's close to the border of fuel starvation. I've seen this happen because the wastegate was too small. If the owner had just bought a larger wastegate, instead of an "adequate" one he wouldn't have been in this predicament.



Size the wastegate so that you can run the LOWEST amount of boost possible. Then use your boost controller to turn boost up. [/quote]

Yeah, that's exactly what I was saying. Sizing a wastegate isn't an exact science. It just has to be big.
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