Sorry I know this has been thrashed out a few times but I wondered if anyone knew anything a bit more up to date.....

Heard that SUL + NF can be better (less DETECTED knock anyway!) than Optimax + NF.

I was going to add the recommended 5ml per litre to optimax and fo a ECU reset cos I have a MY95WRX, but people have said booster works better with SUL. Anyone know why cos this doesn't make much sense unless there is some detrimental chemical reaction between NF and the additives in Optimax ? Or is it cos say Esso SUL is not enhanced/boosted NUL but proper long-lasting 97RON ?

Anyone got any thoughts?

Cheers
Alex

 

Sul + Booster better than Optimax plus Booster.....errrrrr....arhhhhh - dont think soooo..

I think you'll find that yu can advance the ignition more with the Optimax than with SUL - I only use SUL in an absolute emergency... and then only with a full bottle of NF - that said I've only had to use it a couple of times..

1.6 Ron minimum more on Shell Optimax... never heard of a problem between Optimax and Booster.. then again you can get bad batches of all fuel - I suggest you put in a Knock Link which would show you problems with bad fuel........

 

Nice one Steve - I will be using Shell Optimax as per usual then !

Damn must now plan the journey to Anglesey with that in mind