ac123 Posted February 18, 2023 Report Share Posted February 18, 2023 My VE numbers seem off - they are in the 80s at idle and only mid 90s under full boost. Car is driving pretty well otherwise but it feels like something is off in my map. When I tried to change my AFR, it was setting it too rich so I kept lowering fuel charge cooling coefficient to what it's at now (1.0). Attached map and datalog with some part throttle driving and a few WOT pulls. Full spec list: - 1991 MR2 turbo NA chassis - Late JDM gen 2 3sgte swap - Stock ignition system (distributor) - Link G4x extreme PnP ecu (Link MR2LinkV1) - Stock long block (unopened), ~100k miles on it - Borg warner S252sxe turbo, .63 turbine - Precision 39mm wastegate - Delphi 120lb fuel injectors (1200cc) - Stock FPR (43psi base pressure) - Walbro 255 fuel pump (direct wired to battery with separate relay) - GM flex fuel sensor - GM flat response knock sensor - Fuel pressure sensor - aem 30-4110 uego wideband - 3-port boost solenoid - TurboXS bov - 4" intake - 3" catless downpipe and berk exhaust - Screamer pipe - Upgraded side mount intercooler - Fidanza flywheel and southbend stage 2 daily clutch (425tq limit) flex fuel street tune.pclx tuning flex fuel map driving home at end of night.zip Quote Link to comment Share on other sites More sharing options...
Adamw Posted February 18, 2023 Report Share Posted February 18, 2023 Geez, nasty old injectors. They are low impedance arent they? Are you running them with ballast resistor? What fuel pressure sensor are you using? The 7bar cal you have assigned is for one of the old Link MAP sensors so I suspect it may not match what you have. Quote Link to comment Share on other sites More sharing options...
ac123 Posted February 18, 2023 Author Report Share Posted February 18, 2023 I got the injectors and fuel pressure sensor from ATS: http://www.atsracing.com/Parts/Details/F-INJ-TOP The fuel pressure sender says it's a 7 bar one so I picked that calibration. http://www.atsracing.com/Parts/Details/F-FuelPressureAdapter Quote Link to comment Share on other sites More sharing options...
ac123 Posted February 18, 2023 Author Report Share Posted February 18, 2023 Here is another data log from this morning. One thing I notice is the AFR pegs to about 10:1 in boost and the CL correction even says it's adding fuel (but slowly ramping it back). flex fuel street tune.pclx wot pulls way to katies.llgx Quote Link to comment Share on other sites More sharing options...
ac123 Posted February 20, 2023 Author Report Share Posted February 20, 2023 It seems like what's happening is my IATs are very high at idle when i'm sitting, because the temp sensor sits in the intake manifold. I guess this is leaning out the mixture and causing me to use higher VE values to keep it running at idle. My goal was to get the estimated airflow in a reasonable value, but it seems like in order to do that my VE values need to be very high to account for the heat soaking at idle. Quote Link to comment Share on other sites More sharing options...
essb00 Posted February 20, 2023 Report Share Posted February 20, 2023 As what Adam already mentioned, most probably the Link 7 bar calibration table is off compared to what is supposedly used for your fuel pressure sensor. Wasn't there any calibration points/table provided when you purchased the sensor? Are the injector dead times you've there, the ones provided with the injectors? What's the impedance/resistance of the injector coils as measured? About your IAT, you should fill out some values on your 'Charge Temperature Approximation Table'. Refer to the help file for some guidance. Quote Link to comment Share on other sites More sharing options...
ac123 Posted February 21, 2023 Author Report Share Posted February 21, 2023 I’m getting closer. The fuel pressure seems accurate and matches my FPR, and ats confirmed it’s the right calibration to use. I’ve since found my IAT and lambda calibrations were off and I had to make my own calibrations for them. It turns out the IAT number doesn’t change the calculations as much as I thought it did and I’m thinking my wideband calibration probably had a larger impact on things. I haven’t had a chance to try WOT again but hoping fixing the wideband will move the VE table over 100 in boost like you’d expect. Quote Link to comment Share on other sites More sharing options...
koracing Posted February 22, 2023 Report Share Posted February 22, 2023 Your fuel pressure is dropping quite a bit with the regulator you have on there. I think you may need to look at upgrading as I saw some differential pressures down in the 170kpa region. That's definitely not going to help things either and I feel like your dead times are still the largest issue at idle - guessing doesn't work for that kind of thing. Quote Link to comment Share on other sites More sharing options...
essb00 Posted February 23, 2023 Report Share Posted February 23, 2023 I just noticed, does your fuel pressure regulator have a MAP reference vacuum/boost hose (for fuel pressure compensation)? It seems according to your log, fuel pressure does not rise with boost. Fuel pressure even dips on some points - which may also be an indication your engine does not have enough fuel flow from the pump. Quote Link to comment Share on other sites More sharing options...
ac123 Posted February 23, 2023 Author Report Share Posted February 23, 2023 Fuel pump is a new walbro 255. I'm using a stock FPR at the moment, it does have a vacuum reference. As koracing pointed out it looks like my issue might be the FPR. If you look at differential pressure, it actually drops even in the transition from vacuum to positive boost pressure. After that it only slightly rises in boost (not 1:1 like it should). That means i'm losing fuel everywhere except idle. Another log from yesterday: https://drive.google.com/file/d/1pyr1jAoh-whW7je_9VWlF_SSb3x4ivmc/view?usp=sharing Quote Link to comment Share on other sites More sharing options...
Adamw Posted February 23, 2023 Report Share Posted February 23, 2023 I would still be very suspicious of the fuel pressure sensor calibration and woulkd fix that before you go replacing parts. As I mentioned earlier it is highly unlikely that sensor uses the Link 7bar MAP sensor cal. The MAP sensor cal uses a 4.55V span with a 0.2V zero offset, whereas 99.9% of industrial/automotive fluid press sensors like this use a 4.00V span and 0.5V zero offset. Its not going to make enough difference to explain all of the differential press variation you have in your logs but it will certainly exaggerate pressure change above and below mid-span (~350kpa). Have you confirmed you have full battery voltage at the pump when running? Quote Link to comment Share on other sites More sharing options...
koracing Posted February 23, 2023 Report Share Posted February 23, 2023 The 100psi/689kpa Honeywell/AEM cal is more likely to be the correct calibration to use. I asked the vendor what sensor they used and they said either the WHP or some other similar sensor - it would depend on when they sold it. That could explain a lot with the differential pressure measuring so low. Quote Link to comment Share on other sites More sharing options...
ac123 Posted February 24, 2023 Author Report Share Posted February 24, 2023 Checked the sender and it says 100psi on it so I’ll try the other calibration mentioned. Fuel pump is directly wired to the battery via a separate relay I installed so I don’t expect any voltage drop from the wiring. I did notice in a log that my battery voltage steadily drops to about 13.5v under heavy load / high rpm - is that normal? Note: this is on the other calibration - will try the 100psi one today. Quote Link to comment Share on other sites More sharing options...
Confused Posted February 24, 2023 Report Share Posted February 24, 2023 I noticed that my fuel pressure sensor wasn't correlating with the gauge on my FPR. As a man with one watch always knows what time it is, and a man with two watches is never sure, I had to verify with a 3rd source which I was confident was reading accurately. So, I tee'd my FPR gauge, fuel pressure sensor, and the ECU's built-in MAP sensor together, and with an adjustable pressure regulator from my compressor (which had yet another gauge), I found that the fuel pressure gauge was reading incorrectly, but the sensor matched the MAP and regulator's gauge. It kind of seems like the fuel pressure is tracking somewhat with the engine's MAP, but your differential fuel pressure should be pretty solid at 300kpa. Maybe you do only have a ~190-200kpa base fuel pressure without the manifold vacuum/boost reference? Quote Link to comment Share on other sites More sharing options...
ac123 Posted February 26, 2023 Author Report Share Posted February 26, 2023 Update: after installing a new FPR, the fuel pressure is a lot more stable. There's only a 20kpa drop across the rpm range in boost now. Today I'll play with the injector flow rate to see how it affects the VE table. I had to retune the VE table after installing the FPR and this is how it's looking now. Seems closer to reality for idle/part throttle but still quite low for the boost area. Latest map / data log: https://drive.google.com/file/d/1oj9H4cyl_F-vlCGVWqRzB9ywKlgYedp9/view?usp=share_link https://drive.google.com/file/d/13J1Lhyt0hKvsgakn5XqfrBmhldJpHXHg/view?usp=share_link Quote Link to comment Share on other sites More sharing options...
Adamw Posted February 26, 2023 Report Share Posted February 26, 2023 A couple of things that arent right: MAP sensor calibration isn't right. It should be 0.2V = 20Kpa, 4.8V = 400Kpa. So with your current settings you wont be far off under load but at idle and cruise you will reading about 10% higher than actual. You have injector flow rate set to 1100cc in the injector set-up and 1260cc in the multifuel setup. All injectors that I have tested flow less ethanol than petrol. Your multifuel blend ratio table is set up so that 70% ethanol is using 100% of the 2nd fuel properties. But your 2nd fuel properties are for E99. If you are going to tune table 2 with E70 then your fuel properties should be set to E70 values. Your wideband calibration looks pretty strange, what controller do you have? Quote Link to comment Share on other sites More sharing options...
koracing Posted February 27, 2023 Report Share Posted February 27, 2023 He's using an old 30-4110 AEM wideband without a ground reference on the output - I told him to calibrate as necessary to match the gauge reading. Quote Link to comment Share on other sites More sharing options...
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