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Jack
24-09-09, 02:39 PM
How do I calculate the air flow rate of an engine, i.e. how much its sucking in at various RPMs?

I've seen a few calculators and they talk of VE (Volumetric Efficiency) - if thats the case, where/how can I find out the VE?
Southie
24-09-09, 02:47 PM
Is this link any good??? CLICKY (http://www.physicsforums.com/archive/index.php/t-65238.html) :confused: the hell out of me.
Stuart
24-09-09, 03:45 PM
Jack, I shall post my calculations when I get home.... it might just break your brain though lol.

how accurate do you need it to be?
as a rough rule of thumb an engine will consume 1lb of air per 10bhp made (cant remember the tmiing though weather its per sec or per min)
Jack
24-09-09, 07:23 PM
groovy :)

Basically I'm just trying to figure out what size supercharger I may require if I decide to bolt one on. Been looking at Whipple twin screw chargers and trying to see what would be suitable for a 3.0.

I think the Rotrex C30/94 would be good, but its a centrifugal and I can't really fit one of those in my engine bay. Eaton roots style chargers are common buuttt I'd rather not, the engine is hot enough as it is lol
Stuart
24-09-09, 07:34 PM
whats its std power?
Mazz
25-09-09, 09:52 AM
X30XE's are 201/204 iirc - which his will be the same...
burgo
25-09-09, 10:09 AM
Jack, I shall post my calculations when I get home.... it might just break your brain though lol.

how accurate do you need it to be?
as a rough rule of thumb an engine will consume 1lb of air per 10bhp made (cant remember the tmiing though weather its per sec or per min)oooooo i love geeky stuff like this.
dhdev (Oli)
25-09-09, 10:37 AM
There was some geeky air consumption talk in a thread i started here (http://www.pngclub.com/forum/showthread.php?t=104963&highlight=volume)
Southie
25-09-09, 10:46 AM
There was some geeky air consumption talk in a thread i started here (http://www.pngclub.com/forum/showthread.php?t=104963&highlight=volume)

Good god "nerds" lol
Jack
25-09-09, 11:28 AM
210bhp @ 6200rpm. Bearing in mind being a v6 it redlines around 6500-6800
Stuart
25-09-09, 12:58 PM
need more input...
torque/rpm it happens at
cam dutation (not mega vital though)
bore
stroke
inside leg measurement (for my own pleasure)
Jack
25-09-09, 01:45 PM
199lbft @ 3400rpm (270Nm)

Cam duration... pass, whatever the standard is for an X30XE/B308i lol I know the cams are different to the X25, but apparently the same as the Y32...

displacement 2962cc
bore 86mm
stroke 85mm
compression 10.8:1

inside leg, probably jut the right length for your arm to run up there lol