I'm very interested in this product. I've recently fitted a K&N filter, Magnecore 8mm HT leads and a Mark Adams GEMS Tornado chip(s) to my 4.6HSE. Mark was excellent after my initial contact via email and telephoned me. We talked for an hour about the V8 engine that is used in classics and P38's and he knows all about different setups as he tunes many of his customers cars at rolling road facilities around the country. TVR owners also use him and his products.
Anyway, one of the reasons that I was interested in the Vortex was that Mark said that the exhaust sytem actually makes more of a difference than many people think when chipping a V8. The standard exhaust sytem bore is ideal. He told me that he found that customers with large bore exhausts were not gaining as much (if any) power from the V8 via the exhaust. Also he thought the standard 2 pipe (newer P38) were not efficient as the 'Y' conection in the system tended to be a bit more of a 'T' which was not efficient.
Anyway, I'd love to try this Vortex on a standard P38's exhaust system. A sports exhaust system for a P38 costs a wacking £500 upwards. If you can fit a Vortex and get the same effect then maybe this is the answer all P38 and Classic owners are after. Mike - maybe you can contact Mark and see if he would be willing to rolling road a few customers cars before and after the Vortex was fitted?