Took the plunge and installed my JB4 last Wednesday (while g/f was putting up my roof Xmas lights - now that's dedication). The install required the video and the hard copy instructions. It took me 2.5 hours, although I took my time to make SURE I got it right the first time. I can honestly say it should be about 45 min next time. It's kind of scary digging into the guts of the DME.
I wanted to try Map 5 with a blend of 40% E85 (which is available less than 5 miles away) and 60% 91 octane, but I ran out of time. I ran on Map 1 and Map 5 and didn't notice much difference running straight 91. I logged about 400 miles on a long weekend trip and I gotta say I'm very happy with the results. First time on WOT, I saw DTC lights and heard tires chirpping
Power delivery is smooth and strong to redline.
I'll report back when I get some E85 in her and autotune on Map 5.
Any reason to not just clear codes and leave JB4 in for routine trips to dealer (I'm CPO for next two years)?