I dont really agree with banning on a forum unless its a spammer, its a free world if someone banned me from a forum I would just keeo making new usernames up lol
Promotion is a good idea maybe just use a facebook page for events and such to be advertised and only invite paid members to the facebook and redurect them to forum if not a paid member.
Sounds like fuel, air would cause it to bog under load not just cut out, it would also be running rich if the maf sensor is away as the car learns to add more fuel to meet the demands.