| Re: Tips on part-throttle tuning |
Subject: Re: Tips on part-throttle tuning by anesthes on 2010/3/23 10:34:24 Quote:
O2 sensors sees the extra fuel and reports low BLM. It's one of those strange conditions that causes the tuner to keep pulling fuel because the BLM reports like 108 or something silly, and makes the problem worse. Quote:
The narrowband is not perfect. Things get all sorts of crazy when you had a big cam into the mix, because the overlap period is havoc on the 02 sensor. Anything with more than 224 degrees duration, I usually just run open loop and get it dialed in with the wideband. While we'd like to think EFI is great for weather corrections and all that, with such modified motor and 80s technology the corrections hurt more then they help. The true benefit of EFI over CARB is: 1) You can play with crank fueling 2) You can modify timing, idle, fueling without opening the hood 3) You can log RPM vs LOAD vs MPH for WOT fueling at the track, to get an idea of where to add or pull fuel/timing. Since we know that dyno tuning an engine hardly EVER prepares it properly for the track, since a dyno can't accurately simulate progressive load and drag coefficient of an individual vehicle. "Closed loop" is a great idea, and works well on stock motors. When you go crazy with cams and engine combos it's not reliable. -- Joe |
