I'm just wondering how accurate compressor maps are.
For example, when you calculate your air volume for d16 and b16 at 8000 rpm you get the same number....yet we all know a b16 is going to be able to use a larger turbo much more efficiently.
So when we are checking out compressor maps, is it true that all is needed is displacement and RPM....or does compression ratio, and valve lift and duration play a role?
I mean, I'm sure some 1.6 liter corolla engine would do fine with a t25, yet throw that on a b16 and it will just be sucking in hot air (the engine I mean)
For example, when you calculate your air volume for d16 and b16 at 8000 rpm you get the same number....yet we all know a b16 is going to be able to use a larger turbo much more efficiently.
So when we are checking out compressor maps, is it true that all is needed is displacement and RPM....or does compression ratio, and valve lift and duration play a role?
I mean, I'm sure some 1.6 liter corolla engine would do fine with a t25, yet throw that on a b16 and it will just be sucking in hot air (the engine I mean)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by _gurusan_ »</TD></TR><TR><TD CLASS="quote">For example, when you calculate your air volume for d16 and b16 at 8000 rpm you get the same number....yet we all know a b16 is going to be able to use a larger turbo much more efficiently.</TD></TR></TABLE>
Even though a D16 and B16 have the same displacement, they have very different volumetric efficiencies. B16 has a volumetric efficiency somewhere between 102% and 110%, while a D16 will be much much lower. Do a search to see exactly what specific parts affect VE. But basically a more efficient your head and block design the higher the VE of the engine.
When looking at a compressor map you need the flow rate of the engine which you then multiply by the pressure ratio at which you are going to run the turbo. The flow rate of the engine will depend on things like the engine RPM, and the VE at that engine RPM. Compression ratio, valve lift, duration, and things like that will play a role in how efficient your engine's VE is.
Even though a D16 and B16 have the same displacement, they have very different volumetric efficiencies. B16 has a volumetric efficiency somewhere between 102% and 110%, while a D16 will be much much lower. Do a search to see exactly what specific parts affect VE. But basically a more efficient your head and block design the higher the VE of the engine.
When looking at a compressor map you need the flow rate of the engine which you then multiply by the pressure ratio at which you are going to run the turbo. The flow rate of the engine will depend on things like the engine RPM, and the VE at that engine RPM. Compression ratio, valve lift, duration, and things like that will play a role in how efficient your engine's VE is.