I will try and post a new vid with the new equipment tomorrow. I think that it is tuned at 40 hz, I am not real sure though. Here is what the acoustic engineer said in an e-mail from June 27'th.
Yep – this is just what we’ve discussed. Not the prettiest sounding enclosure but still very musical and loud as hell. This is a compound-loading bass-reflex effective down to approximately 35Hz (in-cabin) and audible down to approximately 29Hz. Yes – the woofers and the vent will face toward the rear. For the woofers’ protection, set your subsonic filter between 30-35Hz.