Different wastegate style?
Posted: Tue Oct 14, 2008 6:29 pm
I've been thinking about it for the past week or so, and it seems that wastegates could be installed backwards, and perform better.
On turbocharged cars, the exhaust before the turbine is actually under pressure, as the turbine is a big restriction. How much pressure, I'm not sure, but it is some. Enough to, in addition with the heat, kill oxygen sensors in high output setups. We all know that wastegates start to open before their set boost pressure, causing lag to be worse. Well, in addition to the manifold pressure causing them to creep open, exhaust pressure adds to that. How much, I'm not sure, I haven't actually hooked a boost gauge up to my Y-pipe yet. But even 1psi on a very low boost application (Like mine, 8.7psi), would cause the wastegate to creep open even earlier, further worsening lag.
So what if we just put the wastegate on "backwards," so that the exhaust pressure actually pushes the valve closed more? Much like my BOV, where the intake pressure actually seals it with more pressure. My highly detailed, scaled, blueprint for CNC machining (Blue is manifold pressure, red is exhaust pressure). On the left is how the wastegate is supposed to be bolted on, on the right is my thinking:
Thoughts? I'd try it, but I don't think I have enough room to turn the WG. Anyone else want to try? It should rotate right around, and still bolt in fine. Shaun, care to try?
On turbocharged cars, the exhaust before the turbine is actually under pressure, as the turbine is a big restriction. How much pressure, I'm not sure, but it is some. Enough to, in addition with the heat, kill oxygen sensors in high output setups. We all know that wastegates start to open before their set boost pressure, causing lag to be worse. Well, in addition to the manifold pressure causing them to creep open, exhaust pressure adds to that. How much, I'm not sure, I haven't actually hooked a boost gauge up to my Y-pipe yet. But even 1psi on a very low boost application (Like mine, 8.7psi), would cause the wastegate to creep open even earlier, further worsening lag.
So what if we just put the wastegate on "backwards," so that the exhaust pressure actually pushes the valve closed more? Much like my BOV, where the intake pressure actually seals it with more pressure. My highly detailed, scaled, blueprint for CNC machining (Blue is manifold pressure, red is exhaust pressure). On the left is how the wastegate is supposed to be bolted on, on the right is my thinking:
Thoughts? I'd try it, but I don't think I have enough room to turn the WG. Anyone else want to try? It should rotate right around, and still bolt in fine. Shaun, care to try?