Dry Nitrous and Injector Duty Cycle
06-16-2017, 08:19 PM
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Dry Nitrous and Injector Duty Cycle Brought my stock motor, trans & converter 2k SS to the track last week and ended up running a better time than expected. 11.99@115.50.
Only spraying a .55 jet through the MAF sensor. Here's the odd part. Stock injectors and efi live only shows about 82% duty cycle. Shouldn't I be close to 100% with 120ish shot?? How can I tell if it's a false reading ?
Thanks for any ideas,
Shawn
Only spraying a .55 jet through the MAF sensor. Here's the odd part. Stock injectors and efi live only shows about 82% duty cycle. Shouldn't I be close to 100% with 120ish shot?? How can I tell if it's a false reading ?
Thanks for any ideas,
Shawn
Last edited by 2000ssNX20; 06-18-2017 at 12:10 PM.
06-18-2017, 12:46 PM
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Injector Duty Cycle Hi NX20, yes you have the BEST CORRECT DUTY CYCLE for DRY NOS.
Could this be the reason ?
I manufacture/design Fuel Injectors.
MY REPORT is the most common, BEST, Duty Cycle is from 60-85% with my preference of 80-85%. (NON GDI)
WHEN the Duty Cycle is past 92% the Fuel Injector may STAY OPEN, may operate at x % or other, NOT GOOD.
When at 100% there is NO ACCOUNT for RPM changes, NOT GOOD.
WHEN you state "through the MAF sensor" this could cool the Hot Wire ?
Lance
Could this be the reason ?
I manufacture/design Fuel Injectors.
MY REPORT is the most common, BEST, Duty Cycle is from 60-85% with my preference of 80-85%. (NON GDI)
WHEN the Duty Cycle is past 92% the Fuel Injector may STAY OPEN, may operate at x % or other, NOT GOOD.
When at 100% there is NO ACCOUNT for RPM changes, NOT GOOD.
WHEN you state "through the MAF sensor" this could cool the Hot Wire ?
Lance
06-18-2017, 02:34 PM
#4
Brought my stock motor, trans & converter 2k SS to the track last week and ended up running a better time than expected. 11.99@115.50.
Only spraying a .55 jet through the MAF sensor. Here's the odd part. Stock injectors and efi live only shows about 82% duty cycle. Shouldn't I be close to 100% with 120ish shot?? How can I tell if it's a false reading ?
Thanks for any ideas,
Shawn
Only spraying a .55 jet through the MAF sensor. Here's the odd part. Stock injectors and efi live only shows about 82% duty cycle. Shouldn't I be close to 100% with 120ish shot?? How can I tell if it's a false reading ?
Thanks for any ideas,
Shawn
My assumption: Lower duty cycle than expected equals not all incoming air/nitrous being captured by MAF.
Advise: Add a wideband. That will tell you where you are from a fueling perspective. Adjust spray nozzle position to achieve optimum g/cyl calculation.
On a dry set up, nozzle location and angle can have a huge impact on how MAF registers it.
06-18-2017, 04:57 PM
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I wonder if the fact I Mixed VP Unleaded Extreme 110 octane with a specific gravity of .845 could have richned it enough to cover up lack of injector ? Of course I guess it possible that a previous owner had they opened up some as well...
Definitely going to get a wideband and install it before playing around anymore.
Definitely going to get a wideband and install it before playing around anymore.
