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My local servo has decided to swap from BP to United which has left me in a bit of a dilemma. The car is tuned and has always run on Ultimate but of course that isn't available now. They have told me their 98 mix is Boost 98 which is an E10. Am I going to run into any tune/detonation problems if I fill up on this because from what I understand the ethanol burns quicker than normal fuel. I'm currently running 22psi with a T04Z with the Ultimate tune

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I always buy United 98 ron. The reason for this is simple. At WOT, my car knocks around 15 with United 98 and 45 with BP 98. The choice for me was clear. Also United is about 7-10 cents a litre cheaper here in Perth. Mate in your case you really should get your tune checked cos different fuels have a huge difference on a car that is tuned close to "the edge" as my example shows above. I've pulled 5 degrees, run 91 octane and the car still goes good :thumbsup:

are you worried about it being too lean on the United 98?

would there perhaps be more detonation protection with the Boost98 considering the higher Ethanol content? i wonder if you could even push it further than bp98......

Or go to a different servo?

Theres only 2 servos where I live so I have a choice of United or 95 Shell Premium.

Cheers for the replies everyone. I have to eventually get a retune done once I get this ice ignition to somehow work properly so I'll do the tune on the United stuff. Just hope the cheaper fuel is still fairly consistant.

Slightly off topic, but I also consistently use BP98 [ultimate] too. On 20psi, under WOT, I get quite a high knock (35 - 55, depending on load and temp) .. The car was tuned on Melbourne BP98. Just this past weekend, I went for a longggg drive down the east coast, and filled up at just near Pembula Beach (Shell 'Premium', I have a sneaky suspicion it was only 95), but recorded an absolute max knock of 21. Thats including a WOT run up a *steep* hill in 5th gear, lol.

Plus, netted an extra 50km to the tank range.

IMO, there is simply too much variation in the quality and types of fuel available. Even though my tune is considered very safe, some fuels just dont agree. Kinda like a bad curry.

But, as Elite Racing said, definately worth while getting tuned for the lower quality fuel. Atleast you know you'll be safe when you fill up from the last 1000L of stale fuel from the bottom of the Servo's tanks ;)

BP fuel is crap. BP 98 knocks almost as much as Shell 95. United 98 all the way.

We siphon all other fuels out before tuning and put BP98 from the servo at Stapylton QLD. IMO it doesn't matter where you go, you can get a dodgy owner who can do anything to their fuel and 9/10 they won't get caught. But if you go to a massive servo with a huge customer throughfare, you have a better chance of them being clean/good quality as they have a greater chance of law suit if they f**k up and they are more likely to be tested more often than a small local servo out the back of black stump.

If you are absolutely anal about your tune or the fuel you are running on, buy a bottle of VP Racing octane booster. It costs $20 and will certainly make up for any bad batch of fuel you put in until you can get your regular in there. If you are in a remote area and you are suspicious of the fuel being provided, write a letter to your local member or advise the office of fair trading and see what they can tell you. We shouldn't let these dodgy operators continue to provide poor fuel, we pay enough for the damn stuff!

Where abouts are you in Tassie? Personlly i'd go for a 95 tune. United doesn't cover the state very well, so you could find yourself stranded. 95 and 98 are the only two 'premuim' fules that you'll be able to find statewide.

depends where you are. over here (WA) BP ultimate is the best pump fuel we get, but its by far the most expensive even though BP own the only refinery here....

Mate I'm in Perth. I've bought fuel from BP on Orrong road and that is the shit that knocks to 45. I now go to the United also on Orrong road and it knocks around 15 to 20. BP is not better according to my power fc. Try it mate and see the difference for yourself.

Where abouts are you in Tassie? Personlly i'd go for a 95 tune. United doesn't cover the state very well, so you could find yourself stranded. 95 and 98 are the only two 'premuim' fules that you'll be able to find statewide.

A 95 tune would be the go. Even a 91 tune. I've run my car on 98, 95 and 91. Sure there are big timing differences in the tunes but on the road it doesn't feel a lot different. Yes you can feel the difference but it makes bugger all difference for driving around

Mate I'm in Perth. I've bought fuel from BP on Orrong road and that is the shit that knocks to 45. I now go to the United also on Orrong road and it knocks around 15 to 20. BP is not better according to my power fc. Try it mate and see the difference for yourself.

one example doesnt set the standard. ive had one tank of bp ultimate that needed 8 degrees of timing pulled out under load to stop it pinging its nut off, fuel was obviously stale and shit. but in general bp ultimate is better than the other 98s in perth

one example doesnt set the standard. ive had one tank of bp ultimate that needed 8 degrees of timing pulled out under load to stop it pinging its nut off, fuel was obviously stale and shit. but in general bp ultimate is better than the other 98s in perth

I bought it from the same BP servo for months in a row till I found the United. I buy from the same servo for consistency. Where do you get yours from usually? I'm due to fill up in a couple of days and I'll give it a try for comparisons sake. I don't care about the price difference. It only adds up to $5 a tank anyway.

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