Divided Turbine Housing (T4) vs Undivided (T3)

[Dark_Horse]

I see atpturbo is actually selling a .78 t3 divided housing with a vband outlet. Should be a very interesting housing to say the least.

They're offering that turbine housing on the Borg Warner S300 line too, though I haven't heard of anyone running it.

 

[DirtyBirdRacing]

I wonder, can any one help me figure out how many LBS/MIN my car will be flowing in exhaust?

I know that this thread is really old, but I figured I would answer this question for anyone who comes across it later.

First you need to find the mass flow rate of the air coming out of the compressor. There are many different websites and books that show these calculations. They can take a little while to do (due to messing with compressor efficiencies) but they are quite easy.

Then you need to decide what air/fuel ratio (A/F) you are going to run under boost, most likely 11.0:1.

Then you use this equation to find mass flow rate of exhaust:

mass flow rate of exhaust = mass flow rate out of compressor * (1 + (1/(A/F)))

Example:

Say your turbo compressor flows 50 lb./min of air and you operate at a 11.0:1 A/F Ratio, then:

mass flow rate of exhaust = (50 lb./min)*(1+(1/11)) = 54.54 lb./min


Oh, and about another thing said in this thread, the mass flow rate of exhaust is always greater then the mass flow rate of air entering the engine. Since the mass flow rate of exhaust equals the mass flow rate of air into the engine plus the mass flow rate of fuel into the engine, it has to be greater or else this means that the engine has no fuel to burn, which is lame.

Hope this helps.

Bill