Additional Injector R4 Calculator

[Fstrnyou]

If your MAFCAL is good to start with, I would adjust the R4 fuel map and leave the AP maf curve alone.

[BuddySpeed3]

Originally Posted by Fstrnyou If your MAFCAL is good to start with, I would adjust the R4 fuel map and leave the AP maf curve alone.

Yeah that's what I was thinking also. Ideally, with OL fuel trims disabled I'd like to get the maf curve dialed in almost perfectly with IDC's just touching 100% and then interpolate the maf curve up to 5 volts.

From there, using the R4 calculator I'll ADD 5% fuel and see if the AFR enriches evenly across the rev range. If there are uneven variances I'll tweak that region in the fuel map in order to hit AFR targets and then try another pull. Once AFR is enriched evenly I'll PULL 5% of the maf curve and check again.

I'll do the same for 10%, 20%, etc. Small changes over several fuel map / maf curve revisions.

I'd rather slowly collaborate the aux fuel into the stock fueling curve instead of going straight to adding 30% aux fuel, and pulling 30% of the maf curve.

This way I can ensure that 1) The aux injector(s) are working, and 2) There won't be any significant risks from running excessively lean.

For every percentage increase in aux fueling, and percentage decrease in the maf curve, IDC's will decrease.

So I'll be able to increase boost slightly for every revision. The boost pressure I settle at will depend on how drastic the low side fuel pressure drops from the added fuel demand, and injector manifold delta. I'm hoping to monitor fuel pressure with a gauge.

Once I start to see any sign of fuel pressure drop, I'll decrease boost by 1-2 psi, and settle at that boost pressure.

Then while still monitoring fuel pressure, I'll continue to slowly increase the percentage of aux fuel while pulling the same percentage from the maf curve until my IDC's are around 75-80%. I wanna have IDC's at a safe number to maintain good in cylinder atomization.

Once everything is finalized, I'll re-enable OL fuel trims to account for small variances in AFR.
Hopefully my plan works out

Does anyone want to share some of their experiences tuning 5th/6th port injection?