Which fuel is best for a GC8 WRX
 

Hi all,

New to the forum but not to subarus!

Just wondering about choice of fuel since bioethanol has been introduced everywhere. Ive always been a Shell Vmax fan but my local indy is saying esso premium has no bioethanol so a better fuel.

I've confusingly (mis)read that up to 30% ethanol can help with efficiency in internal combustion engines.

So...I'd love to get your views on this, thanks in advance.

Shell v power , the esso 99 , but the best is tesco momentum as it’s often higher than 99 octane , and cheaper 👍😁

yeh there was a link to a test on here I think a few months ago. The YouTube vid showed a tuned seat Leon Cupra dyno run on various different fuels. Tesco came out the best giving an increase in 5bhp and had the best knock detection additives, closely followed by v power. I’m not sure if the esso super unleaded tested was 99ron or if it was before they introduced that, but the esso fuel was next followed by bp ultimate, which gave pretty much no power gain over normal unleaded and had pretty poor knock detection qualities.

The esso 99 is not available everywhere , but with the cost of tesco being cheaper plus higher octane it’s a bit of a no brainier 👍😁

ha no way...im hoping this isn't a joke as I'm about to fill up on finest...

Going to look for the YouTube vid, thanks for flagging.

Does the ecu map or actual engine make a difference?

Thinking boxer vs inline, mines a gc8 i imagine the Seat is newer.

There was and had surprising results

I'm sure I read recently that Tesco99, which I usually use, was supplied by Esso so should be identical.

I'd only ever used Shell V power for years as that's what the car was mapped with but when we had a V power shortage in my area for wks and wks a couple of years back i took to using Tesco Momentum 99 as a stop gap, been using it ever since and runs fine and a lot cheaper than V power, and even to this day V power ain't always readily available at my nearest Shell garage.

all petrol regardless of brand comes as a base fuel from the same uk refineries. Then the various brands add their own recipe of additives. Tesco fuel is Tesco fuel. They do however have a lot of esso pumps in Tesco express forecourts but I don’t think momentum is the same as esso super unleaded (well, it definitely isn’t according to the above YouTube vid)

Another vote here for Tesco Momentum (Classic PPP). Definitely perkier after using any of the branded fuels.

Also, my only engine meltdown in 100+ cars I've owned or company leased was run exclusively on Shell.
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Probably a coincidence (or wrong octane fuel in the pump) but I've never touched it since. Bit like Jaegermeister...

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Nothing wrong with Jäegermeister
Just need to drop it in some octane booster (red bull)