Backpressure - Can big wastegates help?
#86
Restricted User
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Just something to think about. Suppose in a particular turbo setup, the turbine wheel/housing is the restriction of the hot side. Suppose you've reached a plateau where adding more boost is no longer making any more power due to back pressure. Now also suppose this setup has excessively large waste gates for boost control, and now you want to spray a 200 shot on top of this combo. Would it make the power you would expect from a 200 shot, or would the restrictive turbine/wheel combo still limit power?
Just curious to see what everyone thinks.
Just curious to see what everyone thinks.
#87
TECH Fanatic
iTrader: (16)
But what I'm getting at is, say you have an infinitely large waste gate. It cannot help for turbine back pressure as that would only decrease the amount of boost created (drive pressure and all that). But could it help with the overall "restrictiveness" of the exhaust system, giving the exhaust spent by the added nitrous a place to go?
#88
thanks louis, on 14 pounds it made a little under 700rwhp with high backpressure.... It actually made less power when i cranked the boost up. Now with the backpressure in check, it pulls much harder with more boost! My guesstimate would be 800+ rwhp at 18 - 20 pounds. Think i read somewhere that a restrictive charge side can increase backpressure on the hot side....? Is that correct? Thanks
#89
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I believe it would, anything that slows down the turbine speed can cause back pressure issues, I had a car with an air filter that wasn't sized correctly cause back pressure issues.
#99
Restricted User
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But what I'm getting at is, say you have an infinitely large waste gate. It cannot help for turbine back pressure as that would only decrease the amount of boost created (drive pressure and all that). But could it help with the overall "restrictiveness" of the exhaust system, giving the exhaust spent by the added nitrous a place to go?
For exaggeration's sake, Let's say you have a tiny turbo (35mm T3 tiny) and you are feeding it with a big block v8. Now you have a little 38mm gate on the hotside. It would probably be at full boost at idle even with no spring in the gate and it hanging wide open. Now, you could put your "inifinity" gate on there and it would bypass all your exaust pressure out of it or just enough to keep the turbo spooled all the way up and the rest would go out of it. Not sure if that paints a clearer picture.