112% Injector duty cycle. How bad is that?
04-11-2005, 08:20 PM
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112% Injector duty cycle. How bad is that? I haven't really done any full throttle tuning yet but with my new motor I'm getting 112% duty cycle @ 6700rpm. It is runing at 12to1 right now on the wideband. Do you guys think I need larger injectors or will they be ok once I lean it out?
I have 98 injectors so what would the next step up be?
Thanks
Frank
I have 98 injectors so what would the next step up be?
Thanks
Frank
04-11-2005, 08:30 PM
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You will need bigger injectors. You should probably assume a BSFC of about .55 to be on the safe side.
We did run a 118% duty-cycle on some 160 lb/hr's on a Pro 5.0 car. That was kinda scary though. Haha.
We did run a 118% duty-cycle on some 160 lb/hr's on a Pro 5.0 car. That was kinda scary though. Haha.
04-11-2005, 08:38 PM
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Originally Posted by KingCrapBox
You will need bigger injectors. You should probably assume a BSFC of about .55 to be on the safe side.
We did run a 118% duty-cycle on some 160 lb/hr's on a Pro 5.0 car. That was kinda scary though. Haha.
We did run a 118% duty-cycle on some 160 lb/hr's on a Pro 5.0 car. That was kinda scary though. Haha.
What do you mean by bsfc?
04-11-2005, 09:08 PM
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Brake Specific Fuel Consumption, or the amount of lbs/hr of fuel it takes to make 1 HP. If your BSFC was .5 it would be .5 lbs/hr of fuel to make 1 HP. You can use reverse-engineering to help figure out what size injectors you need. So for every 1 lbs/hr of fuel, you can make 2 HP.
Let's say you've got 30 lb/hr injectors, and you only want to run them at a max duty-cycle of 90%, and you're assuming a BSFC of .5
Potential HP = Injector Size x Number of Injectors x Duty Cycle x BSFC
Potential HP = 30 x 8 x .9 x 2
Potential HP = 432 Flywheel HP
The more effecient your injection system, ignition system, combustion chamber, the lower your BSFC will get.
Let's say you've got 30 lb/hr injectors, and you only want to run them at a max duty-cycle of 90%, and you're assuming a BSFC of .5
Potential HP = Injector Size x Number of Injectors x Duty Cycle x BSFC
Potential HP = 30 x 8 x .9 x 2
Potential HP = 432 Flywheel HP
The more effecient your injection system, ignition system, combustion chamber, the lower your BSFC will get.
