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Discussion Starter #1 (Edited)
CHECK THE INJECTOR CHART...for Supercharger kits...how big do they have to be?

About 4 years ago I found out about this site. Hope this clears up some injector questions.

If you go down the page you can plug in the figures and get the recommended size injector to run. I've found it to work on a couple of cars. One supercharged and another Turbocharged. This may clarify questions about what size injectors to run in your Supercharged kit.

For example: A 440cc injector (basically 42lb's) should be good for 285 flywheel hp...at 85% DC.

Add 10% to the injector size for Supercharged or Turbocharged. BSFC which NA is 0.45 --- moves up to 0.55 Aspirated.

HP (FLYWHEEL)........INJECTOR IN LBS..............IN CC'S
250........................37LBS..........................389CC'S
300........................44LBS..........................462CC'S
350........................51LBS..........................534CC'S
BASED ON 85% DUTY CYCLE. Many racers have run 100% DC for short spurts....all based on engine internals and "Do you feel lucky...well do ya' punk."

There is even information on flow rates to help you decide on FUEL PUMPS @ lbs per hr.

According to the chart and formulas...550lb injectors should be way enough injector for 280-300 lbs of RWHP.

This chart has been known and used on a couple of muscle car sites. So it's not unproven or speculative. Besides, it's fun to play with. :no:

Bottom line ... go with what you feel comfortable with in sizing.

Hope this helps folks!

MegaSquirt - Electronic Fuel Injection Computer by Bowling & Grippo * * ©2009

On the left side of the screen punch up: Injectors and Fuel ...then scroll down a bit for the charts, etc.
 

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^^^ Ah good old MegaSquirt the black box of DIY ecu's. Good find but we all should just cut to the chase and get some 550's and call it day if your adding a supercharger kit.
 

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So it pressurizes fuel and combines it with air?
Not quite - it atomises (by spraying under pressure) a measured amount of fuel into the inlet manifold above the inlet valves where it mixes with the intake air to form the fuel-air charge that goes into the cylinder. The fuel is supplied to the injector under pressure from the fuel rail - pressure is supplied by the fuel pump.
...is replacing one for performance or is it just broken?
Replacement is done with a larger sized injector to allow greater power (along with addition of supercharger etc).
 

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So it sorta thins out the fuel and makes it into a sprayish liquid? And that combines with intaked air, which then goes into the cylinder, and fuels the car? All this time I thought it was just "Fuel goes into fuel tank, makes car go". :D Thanks
 
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