Thanks for the input. I have only 200 miles on the car with the BOE400, nothing on the track so I'm not sure if that is the cause of the problem. That being said, I have beat the car pretty hard with a Katana before the BOE400 so it could have been more than a little compromised. I have a trans build with an OS Giken LSD and Blackwatch 3/4 gears going to happen, I was hoping to get through 1 or 2 track days before I HAVE to do the rebuild. Fred, your assessment matches my experience, it feels like the dogs are not 100% engaged so they can just pop out of gear, seems worse with less load. I will try and adjust the shift cable to see if it's sloppy to get through at least my track day next week.
2006 Elise with BOE 400 supercharger and some aero mods, CRF floating oversized rotors, MCS single adjust coil overs, CRF exhaust, CRF sway bar w/adjustable link, mono-ball pivots, machined steer arms, baffled oil pan, CRF titanium toe link brace, hardened motor mounts, Ethos wheels w/Yoko slicks