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The first assumption that I have to make is that the 50 lb/hr measurement is telling me how much gasoline is being injected per hour.

On that basis, the first thing we can do is convert lbs to grams:

50 lbs/hr x 453.58 g/lb = 22,679 g/hr

We'll next convert grams per hour to grams per minute by dividing by 60 min / hour
22,679 g/hr x 1 hr /60 min = 377.98
Finally we need to get you to cubic centimeters per minute. The specific gravity of gasoline varies, but the reference I found states it as 0.739 grams per cc.

377.98 g/min x 1cc / 0.739 g = 511.47 cc/min

Hopefully that helps out..
Kevin
 

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grease monkey
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Discussion Starter · #5 ·
two different answers, lol gotta love this forum. so which is it? 525cc or 511cc? anybody know for sure? red200se-r, thats a pretty thorough formula, thank you.
Dennis
 

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red200se-r (a.k.a KEVIN) is correct well more so than the other way because he converted from lbs to grams and then hours to minutes which is the proper way to do it (espically in chemistry)


but the other way gives you the general idea

lates
joe
 

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ultimately, the lb/hr doesn't really make sense, and if the world were a perfect one (and metric) it would all be cc/min anyway.

Lb/hr vs. cc/min

Mass flow versus volume flow. Some injector manufacturers rate their injectors based on a mass flow rate. This rating uses the units of pounds of gasoline per hour (lb/hr). Since different fuels have difference weight and specific masses, a better way to look at flow rate is by comparing the volumetric flow rate of the injectors. The volumetric flow rate of an injector is expressed in cubic centimeters per minute (cc/min). To convert from a mass flow rate to a volumetric flow rate, simply multiply the mass flow rate (lb/hr) by 10.5 to find the volumetric flow rate. Hence a 96lb/hr injector would provide a volumetric flow rate of 96x10.5 or 1008cc/min.
 

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SE-R Geek / Nissan Tech
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kevin is right.....pounds (lbs) is a measurement of mass, not volume, like CC's (cubic centimeters aka millilitres ML). kevin first converted the pounds to grams (a metric measurement....US/UK "standard" sucks balls)

im a senior in high school and understood this crap. hell i learned it in sophmore chemistry.
 

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sleeper
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no doubt! I always convert to SI first before doing anything. The 10.5 multiplier is a good ball park which assumes a certain value for the specific gravity of fuel (which is dependent on the fuel type used). But hey, what's a couple percent here or there.
 
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