ask saint steve
imo most of these products such as redex and those cheapo octane boosters are a waste of money
my advice would be to treat her to an extra oil change, fill her up with some vpower (or bp102 if you can find it) and then do an italian tuneup - nice and easy to do yourself and good fun in the process
Why did i know my name would be mentioned
It wouldnt do much mate tbh, apart from loosing you around 10bhp whilst using it, the engine will retard the ignition settings to compensate for the "strange" octane mixture.
In saying that, mine has now down 53k miles, and no hickups whatsover and never underperformed, as has always been a strong bhp performer on the ramps (except when i had a tankfull of it mixed on a dyno day
) which GTijames is referring