This is correct. I actually misread the question.
Fuel injector constant
Race Director
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From: Database Error Indiana
Thread Starter
Le Mans Master
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From: Clearwater Florida
Either way , which number to use ?? my AFPR has a 7psi difference and that dramatically changes the flow at the injectors ... cruise vs WOT
Last edited by C409; Sep 12, 2010 at 11:03 AM.
Race Director
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From: Database Error Indiana
Racer
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From: el cajon ca
hi ,so in 91 vette, using tuner pro rt and the ostrich 2, i have 24 lb injectors and 44 psi at the afpr with no vacum applied, at the constants i found where to change the injector flow rate and i put #24, but is there a place or a table that i change the psi too? my car is running way rich and i'm trying to correct it. thanks
Le Mans Master
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From: Castro Valley Calif.
St. Jude Donor '03 thru '26
hi ,so in 91 vette, using tuner pro rt and the ostrich 2, i have 24 lb injectors and 44 psi at the afpr with no vacum applied, at the constants i found where to change the injector flow rate and i put #24, but is there a place or a table that i change the psi too? my car is running way rich and i'm trying to correct it. thanks
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Racer
Joined: Feb 2009
Posts: 486
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From: el cajon ca
You don't say what bin you're using, but I'm not aware of any PSI table as the ECM only cares about the bottom line. It's commonly recommended by experienced tuners to set your injector constant to what you actually have (24lbs) & tune A/F with your MAF tables to achieve stoich or whatever your motor likes.
Last edited by Ricky 91 vette; Sep 14, 2010 at 12:00 AM.
Drifting
Joined: Mar 2002
Posts: 1,251
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From: Thomson Georgia
I'm glad someone finally paid attention to the 91 in his post, most definitely SD, NO MAF Tables.
You can adjust your injector size upwards several lbs, this will lean the engine down a bit. as it will cause shorter timing to reduce flow. 3-4
Go to the tables and raise your efficiency % by a few and that will also lean a bit. more efficient engine uses less gas to make the same power
Take the .2 volts offset constant out of the MAP table.
Bunches of ways to do it.
Make sure you have good vac to the MAP, use as big a hose as the sensor, itty bitty hose slows response time and can cause a richer? condition as the average vac reading is a bit lower, with table adjustments it will help a cam with a lot of overlap.
You can adjust your injector size upwards several lbs, this will lean the engine down a bit. as it will cause shorter timing to reduce flow. 3-4
Go to the tables and raise your efficiency % by a few and that will also lean a bit. more efficient engine uses less gas to make the same power
Take the .2 volts offset constant out of the MAP table.
Bunches of ways to do it.
Make sure you have good vac to the MAP, use as big a hose as the sensor, itty bitty hose slows response time and can cause a richer? condition as the average vac reading is a bit lower, with table adjustments it will help a cam with a lot of overlap.
Racer
Joined: Feb 2009
Posts: 486
Likes: 3
From: el cajon ca
I'm glad someone finally paid attention to the 91 in his post, most definitely SD, NO MAF Tables.
You can adjust your injector size upwards several lbs, this will lean the engine down a bit. as it will cause shorter timing to reduce flow. 3-4
Go to the tables and raise your efficiency % by a few and that will also lean a bit. more efficient engine uses less gas to make the same power
Take the .2 volts offset constant out of the MAP table.
Bunches of ways to do it.
Make sure you have good vac to the MAP, use as big a hose as the sensor, itty bitty hose slows response time and can cause a richer? condition as the average vac reading is a bit lower, with table adjustments it will help a cam with a lot of overlap.
You can adjust your injector size upwards several lbs, this will lean the engine down a bit. as it will cause shorter timing to reduce flow. 3-4
Go to the tables and raise your efficiency % by a few and that will also lean a bit. more efficient engine uses less gas to make the same power
Take the .2 volts offset constant out of the MAP table.
Bunches of ways to do it.
Make sure you have good vac to the MAP, use as big a hose as the sensor, itty bitty hose slows response time and can cause a richer? condition as the average vac reading is a bit lower, with table adjustments it will help a cam with a lot of overlap.
Safety Car
Joined: Sep 2001
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From: Glenbeulah Wi
You need to put the injector constant at the injector size and reduce your VE table at the rich positions to make the engine run leaner. You can try raising the injector constant but it is a global change that fooling the computer into leaning out the mixture by shorting the injector pulse width. I prefer to give the computer the correct injector constant and then adjust the VE table to give the engine the correct amount of fuel.
Racer
Joined: Feb 2009
Posts: 486
Likes: 3
From: el cajon ca
You need to put the injector constant at the injector size and reduce your VE table at the rich positions to make the engine run leaner. You can try raising the injector constant but it is a global change that fooling the computer into leaning out the mixture by shorting the injector pulse width. I prefer to give the computer the correct injector constant and then adjust the VE table to give the engine the correct amount of fuel.
Last edited by Ricky 91 vette; Sep 15, 2010 at 05:09 AM.
Melting Slicks
Joined: Dec 2008
Posts: 2,772
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From: Mystic CT
You don't say what bin you're using, but I'm not aware of any PSI table as the ECM only cares about the bottom line. It's commonly recommended by experienced tuners to set your injector constant to what you actually have (24lbs) & tune A/F with your MAF tables to achieve stoich or whatever your motor likes.
Dave
Le Mans Master
Joined: Mar 2002
Posts: 5,889
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From: Castro Valley Calif.
St. Jude Donor '03 thru '26
Do you have a known good xdf and ads file for a 91? I have the 'super8d' file off Moats net and looked at a ads file for a SD F body. I have not started tuning yet as waiting for my brake booster to return from rebuilder but do want to make sure I have the correct files to start with.
Dave
Dave
Racer
Joined: Feb 2009
Posts: 486
Likes: 3
From: el cajon ca
Do you have a known good xdf and ads file for a 91? I have the 'super8d' file off Moats net and looked at a ads file for a SD F body. I have not started tuning yet as waiting for my brake booster to return from rebuilder but do want to make sure I have the correct files to start with.
Dave
Dave
