Raising fuel pressure does not change wideband A/F output???
06-27-2012, 11:13 AM
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Raising fuel pressure does not change wideband A/F output???
Okay, here's the setup
Gen VI 502 w/ center mount 2.3L whipple
aeromotive pump and regulator returning to tanks
I'm right at 12.1:1 A/F at WOT. (i'd like to be at 11.5:1) and also be able to adjust w/o changing the cal.
if the cal is changed, richer A/F can be obtained but not when i raise fuel pressure. i can see it on my mechanical fuel pressure gauge but the wideband output is unaffected
has anyone run into this problem? if so, any remedy?
Gen VI 502 w/ center mount 2.3L whipple
aeromotive pump and regulator returning to tanks
I'm right at 12.1:1 A/F at WOT. (i'd like to be at 11.5:1) and also be able to adjust w/o changing the cal.
if the cal is changed, richer A/F can be obtained but not when i raise fuel pressure. i can see it on my mechanical fuel pressure gauge but the wideband output is unaffected
has anyone run into this problem? if so, any remedy?
Last edited by nedpoole; 06-27-2012 at 11:16 AM.
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06-27-2012, 12:05 PM
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Unless you are running the injectors at their maximum physical flow rate (irrespective of pulse width), it does not sound correct that an increase in fuel prssure does not change the air/fuel readings at all rpms. What is your stock fuel pressure and what amount have you increased it to and seen no change in air/fuels? Somethings off here.
Best Regards,
Ray @ Raylar
Best Regards,
Ray @ Raylar
06-27-2012, 12:09 PM
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Unless you are running the injectors at their maximum physical flow rate (irrespective of pulse width), it does not sound correct that an increase in fuel prssure does not change the air/fuel readings at all rpms. What is your stock fuel pressure and what amount have you increased it to and seen no change in air/fuels? Somethings off here.
Best Regards,
Ray @ Raylar
Best Regards,
Ray @ Raylar
i was originally running at 45 PSI when i setup the system. i can raise it to as much as 60 PSI (idle) and not see any difference in A/F output...
06-27-2012, 09:01 PM
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Drop Dustin at Whipple (Whipplecharged) a PM here on OSO and maybe he can clarify what you are seeing as it just does not seem possible unless as I said the injectors at 45 PSI are running thre maximum flow rate with your current programming.
Best Regards,
Ray @ Raylar
Best Regards,
Ray @ Raylar
07-06-2012, 04:44 AM
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If you still have the stock injectors I believe they are 42 lb/hr @43,5 psi (static flow).
45 psi starting pressure should give you 42.7 lb/hr, increasing to 60 psi should give you 49.3 lb/hr if my formulas are correct.
I have also heard that stock (Delphi?) injectors do not respond very well on higher pressures.
Are your pressure regulator boost referenced so that ∆P over the injector remains correct?
45 psi starting pressure should give you 42.7 lb/hr, increasing to 60 psi should give you 49.3 lb/hr if my formulas are correct.
I have also heard that stock (Delphi?) injectors do not respond very well on higher pressures.
Are your pressure regulator boost referenced so that ∆P over the injector remains correct?
07-06-2012, 09:23 AM
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If you still have the stock injectors I believe they are 42 lb/hr @43,5 psi (static flow).
45 psi starting pressure should give you 42.7 lb/hr, increasing to 60 psi should give you 49.3 lb/hr if my formulas are correct.
I have also heard that stock (Delphi?) injectors do not respond very well on higher pressures.
Are your pressure regulator boost referenced so that ∆P over the injector remains correct?
45 psi starting pressure should give you 42.7 lb/hr, increasing to 60 psi should give you 49.3 lb/hr if my formulas are correct.
I have also heard that stock (Delphi?) injectors do not respond very well on higher pressures.
Are your pressure regulator boost referenced so that ∆P over the injector remains correct?
07-06-2012, 11:27 AM
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The injectors that come with a Whipple Merc 496 supercharger kit are not the strock GM injectors that are used in a stock Merc 496.
I believe they are a Siemens 60lb/per hour injector as supplied by Whipple and they all mount in the throttlebody assembly of the Whipple supercharger. Check with Dustin at Whipple for confirmation and exact specs.
Best Regards,
Ray @ Raylar
I believe they are a Siemens 60lb/per hour injector as supplied by Whipple and they all mount in the throttlebody assembly of the Whipple supercharger. Check with Dustin at Whipple for confirmation and exact specs.
Best Regards,
Ray @ Raylar
