Super Unleaded

Shack_attack

Just a quick one, does anyone have a preference of petrol station where they get Super Unleaded from.

I usually use Shell V-Power or Tesco Super Unleaded, I've heard BP isn't as good for performance or keeping the engine cleaner.

Appreciate anyone's thoughts.

fivetide

Mapper once told me V-Power and Tesco were the best.

What car are you putting it in?

Strider590

^^ As above...

Pointless waste of £'s in most cars.

In my Westfield, with a 1979 overbored crossflow engine, heavily modified with 11:1 compression ratios, lightened/balanced internals, stage 2 head, race cam and fixed traditional distributor based timing, it's 100% necessary to stop engine damage.

In anything not a Japanese import and with modern electronic ignition, it's waste of time/money.

But we do have this same discussion every few months

Shack_attack

I have a GT86 and the manual says to use 97 RON or higher.

Apparently having a compression ratio of 12.5:1 requires Super Unleaded?

evoke

Shell V-Power every time.

Strider590

Shack_attack wrote: »

I have a GT86 and the manual says to use 97 RON or higher.

Apparently having a compression ratio of 12.5:1 requires Super Unleaded?

The 2.0 Subaru engine sans turbo, they recommend super (as they do on the impreza) because in Japan they use 100RON fuel. But the electronic ignition will take care of the timing. They couldn't sell it in the UK if it didn't run on 95.

The engine itself is under powered by about 50-100bhp (having driven one for a weekend), leaving the car no faster than the MR2 mk3, but with brakes/suspension that could handle twice the power. It's a very strange car..... Almost like they designed this crazy track day racing car and then thought "oh no, we'd better tone it down or we'll get sued when people kill themselves".

If they release a performance version of the GT86 (probably after doing so on the Subaru BRZ), i'd be more inclined to suggest using higher octane fuel.

The fact that the engine isn't pushed to it's limits, means you have some leeway on the fuel, making every day ownership less of a chore.

w211

I use super unleaded/diesel in my bike and car, just for the engine cleaning detergents, not for the higher octane/cetane ratings.

I use Shell V-Power because of the double points I collect which are converted into Avios.

almillar

In anything not a Japanese import and with modern electronic ignition, it's waste of time/money.

Too general Strider. Yes, Japan has better fuel than our standard unleaded, and if you import a car it mightn't work.
Also, lots of cars ask for 95 (standard unleaded) or 97+RON (super/premium etc) petrol. If they've got knock sensors etc, they'll be able to take the better performance of the higher octane petrol, after a couple of tanks and/or an ECU reset after you're sure you've got rid of the 95 stuff.
Message is - no hard or fast rules, read your manual for YOUR car.

Strider590

almillar wrote: »

If they've got knock sensors etc, they'll be able to take the better performance of the higher octane petrol,

Well... Yes but no. Higher RON fuel doesn't give greater performance, it's purely that high performance cars need it to run at designed capacity.

The definition of "high performance car" is generally something not sold to the average Joe Public.
Remember we call anything with a soft roof a "sports car", from a Ferrari down to a Street KA.

People are too stupid to heed advice to run on high RON fuel, manufacturers would be slated all over the news/media/etc if they started saying "oh yeah it exploded because you used the wrong fuel". As such you won't get many production cars that need it at all.

Except maybe old motors from the 4star (98RON) and 5star (100RON) petrol days.

Carcluster

Can probably find comparisons on line - 5th gear did one a while ago (i THINK v-power had good results).
as regards supermarkets, I read that they source from different places do the actual fuel can really vary - plus always use a busy station which means the supply gets changed regularly as it can lose it's oomph over time.

worried_jim

Carcluster wrote: »

Can probably find comparisons on line - 5th gear did one a while ago (i THINK v-power had good results).
as regards supermarkets, I read that they source from different places do the actual fuel can really vary - plus always use a busy station which means the supply gets changed regularly as it can lose it's oomph over time.

5th gear went for v-max and Tesco. When they tested BP it gave the same performance as regular BP fuel.