Quote:
Originally Posted by jamesm
- Get the injectors right first before you go modifying anything else.
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Yup, this is very often overlooked and why i plan to do fuel pump and injectors while i am still NA
Quote:
Originally Posted by jamesm
- Don't just go hacking away at the maf scaling.
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Very very true, more often than not you can tweak the individual scaling (port vs di) to get your trims closer to zero (or tweak both together) but you need to pay attention to which system is active. For example.. cold cranking is 100% port, cold high idle is combined port and direct, cold kick down idle is 100% port hot idle is 100%DI.
Quote:
Originally Posted by jamesm
- Just because your car idles perfectly with low trims doesn't mean your ports are scaled anywhere near properly. The car idles on 100% direct injection, so simply sitting there at idle and watching trims won't help you.
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See above, only DI idle after warm up, you can actually here when it flips over from port only idle
Quote:
Originally Posted by jamesm
- When fine-tuning the maf, you might see an area around 1.2-1.6v that is more erratic with more scatter than the other areas before and after it, and it won't respond predictably to changes. In my case, this was caused by discrepancy between the accuracy of the port and direct injection configuration. if one is more 'off' than the other, it causes a swing in the afr/corrections. they both need to be right, basically. this matters more if you're on e85 and have rescaled the direct injection as well as the port.
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Yup, as i mentioned above, anyone working on scaling need to log di time, port time, and or the injection mode... you have to get the two systems balanced before you worry about maf scale too much.
Quote:
Originally Posted by jamesm
- if you're trying to tweak injector latency, you can set the whole map to 100% port injection and then collect your logs, filter and process the data to eliminate most of the noise introduced by direct injection.
- when you switch to e85 and have to scale the direct injection, introducing another variable into the whole mess, you can set the map to 100% direct injection and do the same for closed loop to get an idea where it needs to go.
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Good tip, i may try that when i do the pump and injectors
Quote:
Originally Posted by jamesm
- no matter what i do i can't fix an issue where the car goes rich on deceleration. my best guess at this point is that there is another map in ipw like the ones mentioned above or something that isn't defined. luckily it doesn't seem to effect much except an occasional puff of smoke coming to a stop.
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you probably need to adjust the top row (lowes g/s row) of the DI scale table, decel will probably be under DI control and at a lower maf g/s than idle so you should be able to reduce the gdi flow rate some there. Get some logs of the rail pressure and maf g/s during decel and you will see where you can try to adjust, will probably be low rail pressure as well as low g/s/. There are also some overrun fueling tables now in romraider you might look at.
Quote:
Originally Posted by jamesm
- tip-in tuning is a bitch. it also effects drivability a lot.
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Cam timing has a lot to do with the tip in area. I found that running too little retard on the exhaust cam (bigger number = more retard) in conjunction with too much advance on the intake side would induce more tip in knock and in some cases steady state part throttle knock like going up a hill in a higher gear right around the .6 to .8 load range... you can try bigger numbers in the exhaust cam map and smaller numbers in the intake cam map in the problem area, just go 5 at a time on each map till you find the sweet spot... also be sure to ramp smoothly.. ignition, fuel, cams, etc
Ohh and sorry i didn't get back to you about your base map man... major life changes happened and i got busy as heck moving to socal. But I'm getting settled in now. If you need anything give me a shout
Great tips btw
