Actually, I already did refute your claim. At least twice. The situation you propose is nonsense. I'll try one more time.
It is physically impossible for the same engine, at the same speed, and same manifold pressure, and same air temp, to consume air at a different CFM. If the engine cannot consume air at a different CFM, then it impossible for two different superchargers to supply air at different CFM given all else also being equal as you propose.
There also needs to be clarification of what you mean by CFM. CFM specifies the volume flow rate. That's missing a lot of crucial info. What matters is the mass flow rate, and that depends on the pressure and temperature of the air. So are we talking CFM of atmospheric air flowing into and through the the entire supercharger+engine system, or are we talking about the CFM of manifold air (at boosted pressure and temperature) being ingested by the engine? Let's not get hung up on answering this. I'm just pointing out that CFM by itself is ambiguous.
1) For the rest of this post, I will specify the context whenever I mention a volumetric flow rate to avoid ambiguity.
2) Let's also, for simplicity, assume that the engine is perfectly efficient at pumping air. Each cylinder displaces 0.6L of volume, so let's assume it consumes exactly 0.6L of air from the manifold with each complete cycle. This means that, whatever pressure/temperature the air is in the manifold, 0.6L of that air at that same pressure/temperature fills the cylinder.
3) For the sake of working with real numbers (and easy calculations), let's assume we are looking at the engine running at 2000 rpm.
So we've got 2000 / 2 complete cycles per minute of 6 cylinders consuming a total of 3.6L of air from the manifold with each complete cycle.
3.6 * 2000 / 2 = 3600 L/m of manifold pressure/temperature air being consumed by the engine.
4) For simplicity of calculations again, let's say that ambient pressure is 14.7 psi, and the superchargers in question are doubling the pressure, giving us 14.7 psi boost at 2000 rpm.
5) For simplicity of calculations yet again, lets assume no increase in temperature due to the compression. Your scenario assumes the same intake temp for both superchargers, anyway, so there's no difference in temperature to take into account between the two superchargers.
6) So... with this simplified hypothetical situation, I think you can agree that the engine is consuming 3600 L/m of intake manifold air. That intake manifold air is boosted to double atmospheric pressure, which means it converts to double the volumetric flow rate of air from the atmosphere: 7200 L/m. This means that 7200 L/m of ambient temperature atmospheric pressure air is flowing through the supercharger, being compressed down to half the size, double the pressure.
7) Now let's say that you insist that while supercharger A is flowing that 7200 L/m, supercharger B is actually flowing 10% more air, or 7920 L/m from the atmosphere. The engine is still only consuming 3600 L/m of manifold air. If we again, for simplicity, assume no temperature change during the compression, that means that manifold pressure MUST be 7920/3600 = 2.2 times atmospheric pressure. (2.2 * 14.7) - 14.7 = 17.6 psi boost, compared to supercharger A's 14.7 psi boost.
CONCLUSION: The only way to get a different flow rate on the same engine, same engine speed, same amount of boost, and same ambient atmospheric conditions, is to have a difference in compressor/intercooler efficiency or different flow efficiency of intake piping that leads to a different intake temperature, causing a difference in density in the intake manifold.
BUT WAIT! THERE'S MORE!
But how much of a difference could there be due to temperature? Let's revisit the original situation that sparked this debate: 2000 rpms, RIPP vs Prodigy. Same amount of boost, but RIPP claims about 40% gain in torque compared to essentially zero gain demonstrated by Prodigy at the same engine speed, same boost levels. You proposed that a difference in CFM is probably the explanation. For this to be true, RIPP would need to be flowing approximately 40% more air (assuming difference in tuning is not a major factor... which is what you are assuming by claiming that difference in CFM is the major factor).
I have just demonstrated that the only way the CFM could be different is due to differences in intake temp. Let's see if it's possible for RIPP to have intake temps low enough to explain a 40% gain in flow rate...
According to my data logs, intake temps are only about 5-10*F above ambient around full throttle at 2000 rpms. So let's say 70*F ambient temps, intake temps are 80*F. The absolute best case (but practically impossible) scenario is that RIPPs intake temps have no increase over ambient temperature.
So it comes down to how much more air by mass per volume (aka, density) is there in the intake manifold at the same pressure but only comparing a difference of temperature between 70*F and 80*F?
Density of air is inversely proportional to temperature. But not in Farenheit or Celsius. In Kelvin.
70*F = 294 K
80*F = 300 K
So the density of air in the the manifold for Prodigy in this example is proportional to (1 / 300)
The density of the hypothetical best-case-scenario RIPP in this example is proportional to (1 / 294)
Since the pressure is the same, we can proportionally compare those numbers. To find out how much more air by mass is flowing through for the RIPP in this example, divide the proportional density values (RIPP / Prodigy):
(1 / 294) / (1 / 300) = 300 / 294 = 1.02 -> only 2% more air by mass for RIPP.
Or you could also call it 2% more CMF in relation to atmosphere. So yes, technically you were correct in saying the CFM could be different, but it can't possibly be different enough to explain the supposed 40% discrepancy between RIPP and Prodigy gains at 2000 rpm.
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