| Roy I would be interested in the outcome if you go for the upgrade, as I am currently building my 998 Hybrid which is using a 998BP engine with a full 50mm system at the moment but alread have the 50/54mm half system and ECU.
I'm hoping this will give me more than enough power for the road when set up correctly, but if a decent amount of extra ponies doesn't cost to much I may be tempted. | 
skidlids
Hybrid Mode
