Muskrat
Well-known member
With my plans for a turbo upgrade, and going to an external recirulated 02 housing setup, I've been thinking about this a bit. (AKA trying to decide between MAP [thinner 3/8" flange - direct flow] or PR O2 housings [thicker 1/2" flange - 90* flow])
What, in the end, is the ultimate effect on performance with a 90* re-entry angle? Obviously both will work, but is there a distinct advantage of a more direct re-entry angle? I'm relating back to my college fluids class from three years ago, so I may be a bit rusty. Hopefully someone with more expirience with fluid dynamics can chime in.
The exhaust comming out of the turbine is already very turbulant, so any dirruption to flow shouldn't really affect this.
It also takes energy from the main exhaust stream to redirect the exhaust particles from the wastegate, and the exhaust particles from the wastegate lose energy as they collide with the tube wall. What would be the affect of this? Would it create a higher pressure zone immediately after the wastegate re-entry?
This would cause higher back pressue in the exhaust (would it be significant, in the grand scheme of things?) possibly causing increased spool time. This could also have an effect on boost control response. More backpressure at the re-entry means less air can be diverted and you'll have a tendancy to spike to higher boost levels at lower target pressures. The question is, is the backpressure significant enough to affect this in the real world? Or is it just bench racing?
What's your opinion?
What, in the end, is the ultimate effect on performance with a 90* re-entry angle? Obviously both will work, but is there a distinct advantage of a more direct re-entry angle? I'm relating back to my college fluids class from three years ago, so I may be a bit rusty. Hopefully someone with more expirience with fluid dynamics can chime in.
The exhaust comming out of the turbine is already very turbulant, so any dirruption to flow shouldn't really affect this.
It also takes energy from the main exhaust stream to redirect the exhaust particles from the wastegate, and the exhaust particles from the wastegate lose energy as they collide with the tube wall. What would be the affect of this? Would it create a higher pressure zone immediately after the wastegate re-entry?
This would cause higher back pressue in the exhaust (would it be significant, in the grand scheme of things?) possibly causing increased spool time. This could also have an effect on boost control response. More backpressure at the re-entry means less air can be diverted and you'll have a tendancy to spike to higher boost levels at lower target pressures. The question is, is the backpressure significant enough to affect this in the real world? Or is it just bench racing?
What's your opinion?