VE Table maxed at 200 (proper injector data entered) | AEM
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FRS2000
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VE Table maxed at 200 (proper injector data entered)

Hey everyone,

I have a f20c road race engine. Running the infinty 506, engine has ITBs and big cams. Everything is setup correctly from what I can tell. I run ID1700x injectors and have copied all injector data from there website. Fuel pressure is fixed and set at a static 55psi. The VE table is maxed at 200 up top and still goes lean. I am running e85 and know the ve table should peak somewhere around 100. Could really use some help getting this issue fixed so I can finish tuning.

Thanks in advance for the help.

EvoNate
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Did you select E85 as your

Did you select E85 as your primary fuel type in the wizard under Injector Setup?

Has the Infinity been made aware of the 55psi static fuel pressure, either by referencing an installed fuel pressure sensor or by entering the correct static fuel pressure value? (wizard > basic sensors > fuel pressure sensor)

FRS2000
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Yes both are setup. I feel

Yes both are setup. I feel like I have checked everything. Running out of ideas.

FRS2000
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One thing I did find

One thing I did find interesting is I have to set the static at 44 psi for it to register 55ish psi on the battery offset table. I cannot for the life of me figure out why it does not copy exactly what I have selected.

AEM_NS
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Sounds like a fuel delivery
AEM_NS
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FRS2000 wrote: One thing I

FRS2000 wrote:
One thing I did find interesting is I have to set the static at 44 psi for it to register 55ish psi on the battery offset table. I cannot for the life of me figure out why it does not copy exactly what I have selected.

In the Setup Wizard under Injector Setup, do you have Primary Fuel Pressure Regulator Reference set to Manifold Vacuum Reference or Atmospheric Reference?  

FRS2000
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Still not sure why the static

Still not sure why the static fuel pressure I set does not match the injector data table.

It is set to atmospheric pressure

AEM_NS
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I presume you're running a

I presume you're running a MAP sensor. The point of a pressure referenced fuel pressure regulator is that as manifold pressure goes up or down, the base fuel pressure is compensated by the same amount so that the net injection pressure (fuel pressure +/- manifold pressure) remains constant. When you don't have a manifold pressure referenced fuel pressure regulator, your net injection pressure will always be changing based on manifold pressure. So 55 psi base fuel pressure plus -10 psi of manifold pressure at idle will result in a net injection pressure of 65 psi. So "static" fuel pressure from an atmospheric referenced fuel pressure regulator isn't static at all. The system is automatically calculating net injection pressure based on the "static base" fuel pressure and manifold pressure.

FRS2000
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No I don't run a MAP sensor.

No I don't run a MAP sensor. All my tables are based on throttle and my fuel pressure regulator is not hooked to a vacuum source.

AEM_NS
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And what does MAP read?

And what does MAP read?

FRS2000
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It is just reading atmosphere

It is just reading atmosphere so I can have an adjustment for altitude since we race at tracks at various elevations.

AEM_NS
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Well either way bottom line

Well either way bottom line is that you're not getting the amount of injector flow that you've told the ECU to expect. If you're at a VE value of 200 and want it to be 100, you'll have to reduce your VE table and the injector flow table by 50%. Cutting that injector flow value in half is realistically the amount of injector flow you're actually getting. So like I was saying before, this data points towards being a fuel delivery issue. Are you sure it's running on all four cylinders? Definitely have good O2 readings?

You might want to post your cal and a log showing a WOT pull. Perhaps you've got something set incorrectly but I can't think of anything that would skew things by 50%.

FRS2000
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I'm going to add an

I'm going to add an additional fuel pressure gauge tonight.

FreakshowFPV
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AEM_NS wrote:

AEM_NS wrote:

Well either way bottom line is that you're not getting the amount of injector flow that you've told the ECU to expect. If you're at a VE value of 200 and want it to be 100, you'll have to reduce your VE table and the injector flow table by 50%. Cutting that injector flow value in half is realistically the amount of injector flow you're actually getting. So like I was saying before, this data points towards being a fuel delivery issue. Are you sure it's running on all four cylinders? Definitely have good O2 readings?

You might want to post your cal and a log showing a WOT pull. Perhaps you've got something set incorrectly but I can't think of anything that would skew things by 50%.

 

Had a very similar issue to yours OP just recently.  In my case, the injector data was entered by someone else and it was wildy incorrect.  Followed AEM_NS's advice and corrected the injector data and adjusted my whole VE table down by about 25%.  Instead of hitting 200 up top and still going lean, I'm at more like 145 up top and its still rich.  Sounds like your injector data is correct, but something does seem to be causing your injectors to flow less than the AEM expects.  

FRS2000
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I looked into the injector

I looked into the injector data more. I found that the pre set data for the id1700 is different from what Injector dynamics has on their website. Can anyone clarify what the correct data is for the ID1700.

AEM_NS
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We've always had good results

We've always had good results using AEM-derived injector data vs ID's supplied info. Seems like the ID flow bench is a little on the liberal side as all the ID injectors we've ever tested flow under their published data. Even if you make this change, it wouldn't explain a 50% loss in injector flow. What your exhaust setup like? Are you 100% sure your O2 sensor isn't reading artificially lean?

FRS2000
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I checked fuel pressure last

I checked fuel pressure last night and it is maintaining 55 psi easily from the Bosch 044 pump I run. The exhaust is a straight pipe out the back. The o2 is in the stock exhaust manifold and new as of last year. Its readings seem accurate as the car runs accurate to what the o2 is reading.

AEM_NS
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If you have serviceable fuel

If you have serviceable fuel filters, I'd check them even if fuel pressure appears to be okay.

FRS2000
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I have 3 and checked all of

I have 3 and checked all of them