sure let me look

 

this was for a 61mm, JDM MAP, 1000cc PTE injectors, 3" TBE, etc.

 

my car runs like crap with anything near 1:1, per my screenshots above. Is there something I may be missing?

 

scaling, O2 feedback on or off, general look of the fuel map. I will post that info next.

 

No IAT, no Baro, just MAP sensor.

 

For those curious, the fuel map change at 270+ load (kpa in this instance) is a result of fuel pressue drop off at 30-31psi.

 

Thanks man! You just inspired me to re-look at a few things, its funny how you start chasing one number or set of values when you could easily do what you want by changing the other table back to more rational values. I'll try it out and see what I come up with. The scaling/latancy values have been so solid for me forever, including cold startup on E85, I hate to change it (I'm on FIC 1050's) but once I make a few changes I'll consider it. Thanks JB!

 

O2 feedback is the devil. The sooner that one gets thrown out the window the easier this will be for most of the people doing it. Always tune the car in full open loop (with the tables not periphery) get it dialed, then turn the trims back on if its how you might prefer.

 

Why do you say to use the tables instead of the periphery bit?

I agree though, running open loop will make your tuning issues a lot more apparent. I can run in closed loop and my fuel trims will hunt around a decent amount, but I'd never know there was a tuning issue. Flip it into open loop and you realize the car may want to idle at 12:1 and cruise at 16:1.

 

I have seen periphery bit disable cause other drivability issues whereas the table only affects the feedback and nothing else. Cruise at 16:1 isnt a problem and 12:1 idle can be cured...thats where the tuning comes in

I dont think its a tuning issue per se, but larger injectors behave differently and can cause O2 feedback loops and the idle will hunt. Tuning in full open loop first does 2 things:

1. In the event of an O2 failure the car still runs just the same
2. Injectors and maps end up closer
3. You learn how little latency changes will affect everything else.
4. Some of the starting issues that people have (which in effect are the car being too lean) are easily and quickly identified.

Some injectors (low impedance and large mainly) just do not play nice. The new EZtune box that FIC released really does make a tremendous difference for these, but its still easier in open loop. Your 1600s and 1650s start acting like 800s and 1000s all of the sudden.

 

Meh, I still see it being a problem if your main fuel map doesn't match your actual AFR. I'm not really content with having a fuel map that doesn't reflect any kind of reality.

FWIW, I'm 95% there on having my main fuel table match my actual AFR under almost all driving conditions. The only place I'm still having an issue is at low airflow rates (<125Hz). I'm pretty sure it's due to the fact that the SD conversion is based on the idea of a correlation between MAP x RPM and MAF frequency, but MAF frequency is not treated as being linear to airflow in the ECU (MAF compensation tables...) where MAP x RPM is linear with regards to the engine VE equations.

 

35R, OmniPower 4bar, PTE 1200cc, E85, 27.5psi across, stock cams, evo 9.



- Bryan

 

In that example I posted, I could have changed the left side of the MAPVE map to less than 1:1 and got the AFR correct at WOT. In addition I could have leaned the 41 and 61 regions on the right side and had my map match the AFR. Potato or Potato at that point, end result is how the other maps affect the main map. I see where you are coming from, but if the map gets it done and is in range I am not too focused on it past that point.

FWIW the map is within 0.3-0.5 AFR at cruise more or less I let it slide. Some might say this is sloppy but its about where a MAF car would be so its easy to remember that way. I might need to retrain my way of thinking.

 

So you start running the car at 10:1 AFR at ~10 psi?

My maps are more similar to GST's where my RPM VE is over 100% and my MAP VE table is showing I have to add a bunch of fuel to make everything work out.

I agree, on one hand it really doesn't matter if the fuel map matches up. But I'd also like to see us get to a point where we have a solid base map for a couple of MAP sensors that people could just grab and load up and have everything make sense. Then it would just be a matter of doing a couple WOT pulls to get the engine VE curve and then back to tuning just like it was MAF based. I don't think different setups will really need substantially different MAP VE tables and any change in setup would just need a change to the RPM VE table.

 

I still personally think that if you have your MAP VE set right, and tune the RPM VE correctly for your feedbacks, then your original rom shouldn't have to change other than a few extra tweaks here and there. I think people tend to get too focused on the "afr" scaling of the fuel map, when in reality I don't think it was ever meant to reference afr exactly, but be more of a visual aid when looking at millisecond times instead.

From what I've seen so far I don't think you'll ever have 2 cars with the same sets of scalings on them. They just seem to differ too much, or user preference differs.