Quote:
Originally Posted by mattallac
Question to rice racing:I have read that the outlet from the waste gate to the exhaust needs to be at least 18 inches long . What is your opinion on that?
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Probably have to balance outright power at peak rpm to to rest of the power band, bringing the gas in a bit later would not directly impact on the turbine efficiency at a guess.
I don't want to bore people with my technical shit BDC HC style but you can see the pressure build up in the exhaust as the waste gate is cycling to build up the boost to a new higher target (so the high pressure turbine inlet pressure does obviously effect the Turbine outlet pressure in those conditions) Ideal would be to vent the waste gate on its own for mega powered set up's, but I do believe that a good balance of exhaust pressure (turbine outlet pressure) to (intake manifold pressure)
actually improves the engine power band. If its way lower it will give you more top end but at the expense of mid range power/response. This seems to have an effect even on stock ported rotaries.
I have a nice detailed picture of the 2lt 145 inches of mercury boosted 3SGTE motor in Millen's Pikes Peak Racer and that thing at 950bhp does not have the WG 18 inches down stream (it does go right back into the exhaust outlet shortly after the turbine exit), so go figure, maybe he should have read the internet more
