Talking about fuels ,here is a strange one . A few people I know of , with hi performance cars/ engines and running Carbys ,have had fuel problems with the Carby flooding and fuel coming out the vent tubes . Been happening on the race tracks ,street and on dyno s . We have tried everything to stop this happening and wondering why . Myself and a top dyno guy think as all the engines were running BP 98 it's the BP fuel additives causing the problem . The only way we think we have solved the problem is running return lines back the the tank even with mechanical fuel pumps .