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Discussion Starter #1 (Edited)
In order to select the correct size injector for your application, you might wish to use one of the following formulas. <P></P>
-In most cases a naturally aspirated engine will have a B.S.F.C of .50. This means that the engine will use .50 lbs. of fuel per hour for each horsepower it produces. Turbocharged engines will want to be at .60 lbs. per hour or higher.
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-Using these numbers as a guideline, you can select the approximate injector size in the following formula for a four cylinder, naturally aspirated engine at 200 bhp.
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-Most injectors will max out at 80% duty cycle and this is the accepted industry standard.
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-B.S.F.C is brake specific fuel consumption - How much fuel you are using per horsepower per hour
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The proper injector for this application would be 31 lbs. / hr. or 330 cc / min
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To find the HP value of the of the above mentioned injectors use this formula:
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To convert cc / min to lbs. / hr. - Divide by 10.5
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To convert lbs. / hr to gal. / hr - Divide by 6
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To convert cc / min to gal. / hr. - Multiply by .015873
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To find the new FUEL FLOW rate after a fuel pressure change:
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This is a link where the above information was found and where a few good caculators can be found <P></P>http://www.rceng.com/technical.htm#WORKSHEET
 

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Why not add the quick way also? It's normally within 1-2% accurate, and only an idiot wouldn't do it the long way as a final check (Or at least wouldn't leave a good margin of error/extra!)


<P>Injector size in cc /5 = horsepower supported per injector.
HP per injector * # of injectors = horsepower supported.
You can do any other math from that, like *70, 75, 80% for duration (Whatever you want to use)


<P>Comes out very accurate if you stay in the same pressure range! Try it youself!
 

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What about the physical size...and the connectors ????

And the impedence ???

Will 440cc 7mgte fit into the stock fuel rail ??
 
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