Frank B Posted March 12, 2019 Report Share Posted March 12, 2019 im tuning the car the fueling is ok up to 5500 after that it goes super lean 15 afr lean like im out of fuel pump fuel pump base pressure 4 bar i want to know if there is a correction or something on the map that could be cutting my fueling i tried the charge temp approximate table under boost at 100 and 0 does the same thing iat correction on and off does the same thing, the car have 2 new fuel pump and id1000 with a gt35 turbo at 16 psi so i should have plenty fueling im leaving my map and logs to see if somebody can steer me on the right direction or give me some pointers i suspect that i may have some correction or limiter pulling fuel after 5400 but i dont know if this plausible after innundacion no lc.pclr dyno pull 3rd gear.llg dyno pull malo 2 2nd gear.llg Quote Link to comment Share on other sites More sharing options...
cj Posted March 12, 2019 Report Share Posted March 12, 2019 I dont see any limits/fuel cuts/etc kicking in. Your logs dont show the lambda values or fuel pressure though so its hard to get the full picture. Without this I can really only guess Do you have a screenshot of the lambda graph from the dyno from either of these pulls? specifically I want to know if gradually crept up once you were on full boost, if it suddenly just jumped at some point, etc. Is your fuel regulator boost reference working correctly? max calculated fuel flow in those logs is around 2050cc/sec - so around 120LPM which even after losses in the lines etc, you should be able to hit with any decent aftermarket pump (assuming your lines are big enough and the pump has big enough wiring to supply current) Were you feeling misfires as it got above 5k on the 3rd gear pull? your RPM jumps around a little bit which could be misfire or it could be trigger issues. If all else fails, grab a trigger scope at 5400-ish rpm. Quote Link to comment Share on other sites More sharing options...
Frank B Posted March 13, 2019 Author Report Share Posted March 13, 2019 I dont see any limits/fuel cuts/etc kicking in. Your logs dont show the lambda values or fuel pressure though so its hard to get the full picture. Without this I can really only guess Lambda values around .95 / 1.05 once it hit full boost at around 5400rpm Do you have a screenshot of the lambda graph from the dyno from either of these pulls? specifically I want to know if gradually crept up once you were on full boost, if it suddenly just jumped at some point, etc. it didnt crept gradually its like .78 then .95 /1.05 Is your fuel regulator boost reference working correctly? yes its working right its new i dont have a fuel pressure gauge inside the car but we kinda watch it on the dyno max calculated fuel flow in those logs is around 2050cc/sec - so around 120LPM which even after losses in the lines etc, you should be able to hit with any decent aftermarket pump (assuming your lines are big enough and the pump has big enough wiring to supply current) how can i calculate the max fuel flow , im using twin pumps a 340lph + 465lph to a an 8 line to big rails and ID1000 injectors the wire is gauge 8 positive and ground could this be the issue? that could not supply enough volts for 76 psi fuel pressure? Were you feeling misfires as it got above 5k on the 3rd gear pull? your RPM jumps around a little bit which could be misfire or it could be trigger issues. If all else fails, grab a trigger scope at 5400-ish rpm. could you explain a little better the trigger scope part? Quote Link to comment Share on other sites More sharing options...
cj Posted March 13, 2019 Report Share Posted March 13, 2019 Those pumps are kind of overkill and might even be a problem if you just have a single wire feeding both of them. 8gauge wire should be rated for ~73amps draw though so unless there are some weak points/small wires/fuses/etc further up the wiring this should be the problem. You could get a friend to hold a multimeter across the pump terminals and verify that you still see ~14v when it starts to fail just to rule it out. [edit] what do your fuel pickups look like? if you are sucking a large amount of gas out of the tank at once and through small pickups you might be causing cavitation/air bubbles in the fuel. there are 2x back of the envelope calculations you can you to estimate fuel pump size 1) 4x 1000cc (per sec) injectors x 60 seconds = 240LPM max flow through your injectors @ rated pressure @ 100% injector duty cycle. your injectors and pump(s) will have a different flow rating at different pressures, typically the rated flow is at 43.5psi (3bar) and drops a bit at higher flows, but some pumps actually increase their flow at high pressures, and most injectors flow more so you really need the spec sheet to confirm this. 2) horsepower / 2 = LPM requirement. Assuming you have 400 BHP, you need ~200LPM (on petrol) for example the walbrough 465 pump spec states: 465 LPH @ 40PSI & 13.5 Volts, 360LPH @ 120PSI & 13.5V. The trigger scope part is that these engines can get "noisy" at higher rpm which can throw off the RPM triggering which then causes all kinds of thing to go wrong around spark and fuel numbers. The trigger scope feature in the ecu is like an oscilliscope that shows you the trigger voltages and pattern the ECU is seeing. With the engine running, click ecu controls -> trigger scope, and then save the log file it creates. This only take a couple seconds. Please grab one log at idle, and another with the engine at 5500rpm Quote Link to comment Share on other sites More sharing options...
Frank B Posted March 13, 2019 Author Report Share Posted March 13, 2019 5500rpm no load right just accelerating while parked what do you mean fuel pickups like the fuel pump filters? Quote Link to comment Share on other sites More sharing options...
cj Posted March 13, 2019 Report Share Posted March 13, 2019 filters, sizes of the pipe between the pump and the tank if they are external, everything that will be under suction instead of pressure when fuel is pumping. Do you have a surge tank and/or feed pump for this? Quote Link to comment Share on other sites More sharing options...
Frank B Posted March 13, 2019 Author Report Share Posted March 13, 2019 2 fuel pumps inside a tank with their filters Quote Link to comment Share on other sites More sharing options...
cj Posted March 14, 2019 Report Share Posted March 14, 2019 sounds like its not going to be a fuel problem then. A few things you could do to rule it out but i'm leaning more towards triggering issues from what you've said so far. Quote Link to comment Share on other sites More sharing options...
Frank B Posted March 16, 2019 Author Report Share Posted March 16, 2019 i think my trigger is indeed funny im 10 deegrees over on my tune and still making power dyno log 443.llg idle 2.llg Trigger Scope Log 2019-03-15 10;48;56 am idle.llg vp map 450.pclr Quote Link to comment Share on other sites More sharing options...
Adamw Posted March 16, 2019 Report Share Posted March 16, 2019 There are no signs of trigger issues in any of your logs, dwell is rock solid and RPM looks believable. What do you mean by "i think my trigger is indeed funny im 10 deegrees over on my tune and still making power". Have you checked the trigger offset with a timing light and confirmed that you get the commanded timing at both high and low rpm? Quote Link to comment Share on other sites More sharing options...
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