nah ive been told a hundred times you can run the a-series motors on premium as they came with hardened valve seats

i always use it, i prefer Synergy as it is more consistant than Optimax

the car HAS to be tuned for premium unleaded to see any benefits in using it

um i had a mate that worked at a shell servo and he said he would get batches of complaints from customers every now and then with huge mechanic bills, the mechanics blaming the fuel they used for expensive damage to there engines

plus i also here shell has a huge batch of fuel they made at the moment that is dodgey and they are trying to find a way to modify it so they can sell it

enough to keep me away from shell, stick to the synergy i reckon (has same octane as optimax)

optimax was the highest rating a while ago (like when the PRC rules changed), but since then both mobil (synergy 8000) and BP have brought out equivalents