Hey guys. I have been wondering about this for awhile, but haven't posted because I wasn't sure if I just didn't know how to tune or if this is really abnormal or not. My curiosity has gotten the best of me so I really want to know and the car has been running just fine for awhile now so I am pretty sure the tune is fine.
Last summer I installed a set of IPS 19Ts as the start to some beyond BPU mods to my car. Prior to this I had just been BPU, running a Walbro (stock wiring though), stock injectors, SAFC2 with 0 correction. After getting the new turbos installed, I kept my boost controller set to where it was set pre-turbo upgrade (about 14.5psi). I knew that I would be getting more air up top, but since my boost is so low, everything should be about the same in the low-mid range. At this point I tuned most of the low rpm settings on the SAFC using my wideband a paying a little attention to the fuel trims as well. Everything went well, but I ended up with nearly -10% correction across the board. This seemed very odd to me, but it was only the low throttle settings so I wasn't too worried about blowing up the motor, plus the wideband and datalogger (no knock, trims much closer to 100% than they used to be) seemed to indicate everything was just fine.
Anyway, I was worried that I didn't know what I was doing so I had a friend help with the high throttle tune (besides I wasn't about to try staring at all the gauges by myself). He has a lot of SAFC tuning experience and knows what he was doing, but does a lot more work on Hondas, not like that should matter. And just as the low throttle settings, the high reflected the same! We actually didn't even totally finish the tune, but as it stands, the four data points I can remember from memory are 3400 = -6%; 4000 = -9%; 4600 = -11%; 5200 = -12%. To be honest, the 5.2k rpm point is still a little rich too, and maybe even the 4.6k one. It seems totally bizarre to me that we are pulling so much fuel on a mainly stock car, so I wanted to ask the experts: Is this really normal? I know the stock ECU is rich, but > 10%? I plan to wire my wideband into the datalogger sometime this week and then I should be able to finish up the tune from my logs, but it just seems wrong to me. Although, I am getting some knock up top, however, the knock only seems to occur when I am at an AFR in the 10's. I always let off as soon as I hear the alert for > 6 counts of knock. I was shooting for 11 across the board with those numbers listed, because I didn't want to try to go too lean, but I never thought I would need to pull so much fuel.
To be honest, I have never touched the injectors on this car, although it wasn't modded at all when I bought it 7 or 8 years ago (from a dealer). I can't imagine the injectors are not stock... but maybe? I hope someone with more experience can chime in and tell me whether or not this is normal, or if I should be concerned.


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