N55 JB4 ISO First look review
This weekend I followed the directions from Terry to modify the JB4 stage 2 board and update the firmware to the ISO firmware. At first the car was behaving oddly, throwing codes and running slow (no boost) etc. But Terry was very responsive and helped us isolate the problem being the P3 vent gauge competing for CANBUS information. With that disconnected, the new firmware kicked in properly and wow, what a difference!!
As a nearly FBO (only missing FMIC) daily driver, I can give my first overview for those that haven't done the upgrade. As a note, I do not run meth or E85, so this is just with 93 octane and the standard mods.
Overall, torque is much more available and boost is delivered far smoother than ever before. The car never feels like it's struggling or fighting itself. My favorite part of the morning is merging onto the highway, right after I get the double flash and hit it to DTC, leaving the car in 3rd around the onramp and throttling out... I couldn't believe how smoothly it delivered the power. It just starts pulling right away and doesn't stop.
I also put it through some of my favorite torture tests to compare it to the old firmware version (overtakes, deceleration to hard acceleration, stop and go in 2nd gear etc.). It handled all of them very well. My favorite test is a long uphill section of highway where I left the car in 6th and started at 60 mph while opening the throttle (no downshift). No hesitation, no bucks or jerks, just smooth delivery of torque and stronger acceleration than ever.
This is a GREAT update, and I highly recommend everyone to run it. Big props to the guys at BMS, especially Terry for his amazing customer support!!