Does anyone know what the airflow thru a rotary engine/an FD engine is in lb/min or cm^3/sec?
I'm trying to check out different compressor maps and am trying to figure out what the airflow/bottem number is for our cars.

thanks

 

You mean like cubic feet per minute (CFM)? Would that work? 'Cuz it seems like a few months ago someone posted something along these lines. Maybe it was in one of the N/A threads....yeah, it seems like it was discussing what a 12A would flow, as this guy was having carb problems. Seems like he was trying to put a 550 cfm 4 barrel carb on a race motor he was building.
Sort of different than what you asked....

That is a good question. I really don't know the answer.
I have a book by Hugh MacInnes that shows all the technical stuff about compressor mapping and all that, but one has to know the base flow of the engine for the formulas to be plugged in.........

 

I found http://www.turbofast.com.au/tfcalc.html but am too lazy or stupid (what ever the case may be) to come up with fake bore and stroke numbers which are the same for a rotary engine for this calculator.

 

I think this is important enough to bring from the dead for a potential answer.

 

for turbofast program, use 3.7" bore and stroke, 4 cyl

(2.6L)

 

Off the top of my head...

Well, if you know the amount of fuel being used and the a/f ratio, you can calculate the amount of air being used. Since a/f is a stoichiometric ratio, you'd evaluate in moles/min and then convert the moles/min of air the into cf/min at ambient pressure and temperature. You can use a/f of about 13, and maybe duty cycle of the injectors by the injector rating to get the fuel input.

Of course, this only includes the amount of air used in combustion. It wouldnt' include air used by the air pump.

 

What air pump?