VE Tuning, Which IFR do I use?
#1
VE Tuning, Which IFR do I use?
I put 37# lucas injectors in my car earlier this year along with a Racetronix fuel pump. But my first datalogs showed all my LTFT's between +6 and +15 so I biased everything down (to a total of 83% of original 37# numbers) to get everything in the negative. I'm sure the higher pressure of the Racetronix pump played some part...
Now I'd like to try VE tuning a little. But which table do I use?
The calculated value, or the corrected value, or something in the middle???
Thanks guys
Now I'd like to try VE tuning a little. But which table do I use?
The calculated value, or the corrected value, or something in the middle???
Thanks guys
#2
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Do you know for a fact that the Racetronix pump
has you at a higher fuel pressure? Pressure should
be set by the in-tank regulator unless you changed
that out too. Though a much stronger pump will
make for -some- change in regulated pressure.
Did you ever read the pressure at the rails? How
does it relate to original?
What, on your car, can you trust? Is the MAF any
kind of normal? Do you have a wideband meter?
You have to find some way of knowing that you have
the IFR table right. If you have a reliable MAF and a
wideband then you could just look at the WOT, 4000-
6000RPM wideband result vs commanded AFR and see
whether you are getting close match, indicating the
IFR is proper (at least in that range).
has you at a higher fuel pressure? Pressure should
be set by the in-tank regulator unless you changed
that out too. Though a much stronger pump will
make for -some- change in regulated pressure.
Did you ever read the pressure at the rails? How
does it relate to original?
What, on your car, can you trust? Is the MAF any
kind of normal? Do you have a wideband meter?
You have to find some way of knowing that you have
the IFR table right. If you have a reliable MAF and a
wideband then you could just look at the WOT, 4000-
6000RPM wideband result vs commanded AFR and see
whether you are getting close match, indicating the
IFR is proper (at least in that range).
Originally Posted by V-10 Killer
I put 37# lucas injectors in my car earlier this year along with a Racetronix fuel pump. But my first datalogs showed all my LTFT's between +6 and +15 so I biased everything down (to a total of 83% of original 37# numbers) to get everything in the negative. I'm sure the higher pressure of the Racetronix pump played some part...
Now I'd like to try VE tuning a little. But which table do I use?
The calculated value, or the corrected value, or something in the middle???
Thanks guys
Now I'd like to try VE tuning a little. But which table do I use?
The calculated value, or the corrected value, or something in the middle???
Thanks guys
#3
Good questions, I'll respond the best I can.
Fact, no, I'm installing an electric fuel pressure gauge over the winter, but right now, I'm just going off of what I could find by the search engine. Typical numbers I've found are anywhere from 60-65psi.
I did not mess with the fuel pressure regulator at all. Nor the pulse dampener.
The MAF is 100% bone stock.
No wideband yet, but I did have it tested with wideband on the dyno a month ago. AFR was 14.7:1 idling, about 12.2:1 at WOT (Had to bias the PE vs. RPM down ~20% when I adjusted the IFR earlier this year because it was making me run 10.8:1 on the dyno at WOT). Also had to reduce the Fuel Air multiplier to get the AFR to lean out.
Wideband AFR and Commanded AFR are nowhere near matching. Commanded at WOT is almost 15:1 now, to get me to where I'm at.
As you can see, this has been quite the headache for me this year, trying to get the car to NOT run rich as hell...
Recommendations, please?
Fact, no, I'm installing an electric fuel pressure gauge over the winter, but right now, I'm just going off of what I could find by the search engine. Typical numbers I've found are anywhere from 60-65psi.
I did not mess with the fuel pressure regulator at all. Nor the pulse dampener.
The MAF is 100% bone stock.
No wideband yet, but I did have it tested with wideband on the dyno a month ago. AFR was 14.7:1 idling, about 12.2:1 at WOT (Had to bias the PE vs. RPM down ~20% when I adjusted the IFR earlier this year because it was making me run 10.8:1 on the dyno at WOT). Also had to reduce the Fuel Air multiplier to get the AFR to lean out.
Wideband AFR and Commanded AFR are nowhere near matching. Commanded at WOT is almost 15:1 now, to get me to where I'm at.
As you can see, this has been quite the headache for me this year, trying to get the car to NOT run rich as hell...
Recommendations, please?
Originally Posted by jimmyblue
Do you know for a fact that the Racetronix pump
has you at a higher fuel pressure? Pressure should
be set by the in-tank regulator unless you changed
that out too. Though a much stronger pump will
make for -some- change in regulated pressure.
Did you ever read the pressure at the rails? How
does it relate to original?
What, on your car, can you trust? Is the MAF any
kind of normal? Do you have a wideband meter?
You have to find some way of knowing that you have
the IFR table right. If you have a reliable MAF and a
wideband then you could just look at the WOT, 4000-
6000RPM wideband result vs commanded AFR and see
whether you are getting close match, indicating the
IFR is proper (at least in that range).
has you at a higher fuel pressure? Pressure should
be set by the in-tank regulator unless you changed
that out too. Though a much stronger pump will
make for -some- change in regulated pressure.
Did you ever read the pressure at the rails? How
does it relate to original?
What, on your car, can you trust? Is the MAF any
kind of normal? Do you have a wideband meter?
You have to find some way of knowing that you have
the IFR table right. If you have a reliable MAF and a
wideband then you could just look at the WOT, 4000-
6000RPM wideband result vs commanded AFR and see
whether you are getting close match, indicating the
IFR is proper (at least in that range).
#4
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Do you have any old logs from before you got the large injectors? If so you could look at your ltrims from before and scale your injector tables until your ltrims are back to what they were when your injectors and injector tables were stock. Unless you changed your whole setup at the same time.
#5
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Recommendations, please?