Premium/regular Petrol Query

[Tommy G]

Hey All. I'm currently running Vortex fuel in my RS-Four Neo. We do a lot of interstate travelling and I'm wondering if there would be any adverse effects of using regular unleaded. Is this just a bad idea?

[GoldZilla]

You should always use Premium in your car, as the Aussie fuels are generally "weaker" than those in Japan (and Europe).

For a bit of insurance, in case you can't find any Premium grade fuels when you're out and about, you should carry a few bottles of Octane booster in your boot. Most bottles fit neatly into the little compartment in the left hand side of the boot.

[sleeper393]

Try not to use vortex premium quite a few people have poo poo'ed the fuel, smelly and not as good as other high octane fuels , eg - shell , bp , mobil. have a look there are some threads on this site that will open your eye's .

Edited January 14, 2009 by sleeper393

[_Ryan_]

shell is the worst!!!

Try your car on BP ultimate, see how it feels after a few tanks.

[pixel8r]

I've found that almost everyone has a different favourite fuel...and it seems some cars like one fuel better than another...

My stageas have both run best on bp ultimate98 - just seems to run smoother, and quieter. I've tried shell vpower but with my last stagea (which had 160awkw) it didn't run as smooth and didn't give any gain over bp, and with my current one (stock m35) i tried it recently on the highway and my fuel economy was about 0.3L/100km worse with shell than bp. Not strictly a scientific comparison but my only advice is that whatever you decide to use, just stick with it, because you'll get the most benefit with repeated use. Using a different fuel every time will not provide any benefit and your car will probably not like it much.

I'd steer clear of regular unleaded - thats about 10% RON less than what the cars were designed to run on. Sure it has a knock sensor but the bottom line is that premium is better for your engine (since these cars were designed to run on 100RON fuel or better). The few $ you save on fuel will cost you in fuel economy, performance, and quite possibly engine problems down the track (depending how long you plan to keep it).

I've always thought to myself - "if you cant afford the fuel (and the insurance), you cant afford the car". In the end I just consider that its just part of the cost of owning a really nice car.

[toddlls]

BP ultimate or Mobil 8000 only, mine runs like a hairy dog on anything else.

Never run normal or 95 without octane booster or you may find funny things begin to affect motor integrity due to lean out thus higher temps

[_Ryan_]

I worked it out that the extra economey i get out of 98 over 91/92 in every car i have owned, has made the price difference worth it per tank. Eg, Save 3bux on the cost of the tank but get 50 less km out of the tank.

[KiwiRS4T]

Always use the highest octane you can get - it is best for your car and should work out just as economical as lower, cheaper grades. Those little plastic bottles of octane booster do virtually nothing and the best of them may raise the octane by less than 1/3 of a point. If you're serious about raising the octane level of 95 or worse you need a couple of 5L containers of toluene.

In NZ (and I believe its the same in Aus) all petrol comes from the same refinery with the brands being different by only miniscule quantities of additives. the only exception is that many oil companies also buy refined petrol on the spot market when it is cheap and different shipments can vary wildly so for me brand loyalty stretches only as far as the cheapest premium (although lately i,ve been buying an E10 blend and in Aus you can get E85 ...interesting thread under "forced induction"on this). The "best" fuel seems to be propane so looking forward to developments in the LPG line.

[Whooby]

There is a couple of shell servo's in QLD that sell 100 Oct. But its 98+Ethanol. Never tried it. Saw it had Ethanol and drove to the next pump.

[Stinky Rooster]

Depends a LOT on where you are too. Here in WA we only get 2-3 types of 98RON fuel, but seeing as though there is only 1 cracking tower (refinery capable of producing 98RON fuel) in the entire state, its kinda a moot point. The only difference in them is a few detergents and stuff blended in that have no effect on the RON.

Having said that though, its kinda interesting that while both U98 (BP) and V98 (Vortex) come from the same refinery, and are both quoted as 98RON, they both have different MON ratings.....

At the end of the day, its all about the SOTP dyno results. I only use 98RON in Teh Fury because km per litre its the most efficient (ergo cheaper)