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magnumv8 · 09-09-2011, 09:07 PM

Here is the formula for selecting the proper injector for your application.....

injector size = HP x BSFC (.5 avg) over number of injectors X duty cycle (80%)

in a normal V8 with 400 HP when you plug in the numbers you end up with 32 lb. injectors....

You want to be a little large rather than too small or even close so that the injector doesn't reach a saturation point where it literally doesn't close but stays open, that is why the duty cycle is at 80% in the formula to give you a little "head room"....

Normal fuel injection flow rates are @ 43 lbs......by pushing the fuel pressure up you can fool the system into "thinking" the injectors are bigger than they actually are, fuel atomization may be a little better with more pressure, but it is best to start conservative and slowly push things until you see if there is any increase in performance AFTER you get a good tune in the vehicle.....

D L Rambo.....

09-09-2011, 09:07 PM	#7
magnumv8 Member Join Date: Feb 2009 Location: Coraopolis, Pa. Posts: 172 Likes: 0 Liked 0 Times in 0 Posts	Re: LT1 fuel injector size? Here is the formula for selecting the proper injector for your application..... injector size = HP x BSFC (.5 avg) over number of injectors X duty cycle (80%) in a normal V8 with 400 HP when you plug in the numbers you end up with 32 lb. injectors.... You want to be a little large rather than too small or even close so that the injector doesn't reach a saturation point where it literally doesn't close but stays open, that is why the duty cycle is at 80% in the formula to give you a little "head room".... Normal fuel injection flow rates are @ 43 lbs......by pushing the fuel pressure up you can fool the system into "thinking" the injectors are bigger than they actually are, fuel atomization may be a little better with more pressure, but it is best to start conservative and slowly push things until you see if there is any increase in performance AFTER you get a good tune in the vehicle..... D L Rambo.....