NB8 91 or 95 ron fuel?

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jerrah
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Re: NB8 91 or 95 ron fuel?

Postby jerrah » Mon Jul 11, 2011 4:14 pm

Regarding the Yaris economy/performance and e10 fuels:
The Yaris (at least the 1.5) has stickers all over it stating that it's designed for e10.

I've found that Shell (and the independents) are the only companies that state their e10 is 94/95RON whereas BP, Caltex, etc are 91.

In a Yaris 1.5 with similar highway driving I can see a repeatable difference of <500km ~ 600km+ per 40L consumed between a 91 and 94/95 RON fuel. Yes I consistently travel 100km MORE per tank on Shell e10.

Bringing it back to the MX5 I get good performance on Shell 94 e10 and it's knock city on any of the other 91 e10's. I have to load a different ignition and fuel map and it really dulls my performance.

Shell 94 is their 'budget' e10 (cheaper than their unleaded 91) and has the bonus of smelling like mollasses when I fill up. 8)

As an aside I always ran BP Ultimate in my VW VR6 which seemed to like it (minimum RON95 recommended).
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Re: NB8 91 or 95 ron fuel?

Postby samx5 » Mon Jul 11, 2011 4:18 pm

The first thing every noob gets told is to advance the timing to 14 degrees, so chances are unless you bought your brand new its been done. If it has you will have to run on 95 or 98. This is a part of what makes this question dubious, as unless youve checked the timing who knows what fuel you should use?

Dann[/quote]
Yes, but mine's an NB8a which is harder to do the timing advance on than an NA6 for example. Agree, the timing test will clear things up a bit.
Was: 1988 Corolla 4A-GE Twin Cam, 1991 Laser TX3, 1995 Peugeot 306 S16, 2003 Astra Sri Turbo, 2007 SP23 Lux
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Re: NB8 91 or 95 ron fuel?

Postby jerrah » Mon Jul 11, 2011 4:19 pm

Note: I get better performance on 98RON but I can tune for particular fuels. I'm running e10 94 because a) it's cheaper b) it's good 'enough' for me.
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Re: NB8 91 or 95 ron fuel?

Postby NitroDann » Mon Jul 11, 2011 4:25 pm

Your yaris must be pulling timing due to knock on 91 if you get repeatable economy improvements on the higher octane fuel. Or your lucky enough to have found a servo who consistantly has a heavier high octane blend.

I also tuned for 95 octane e10 before I went to e85.

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Re: NB8 91 or 95 ron fuel?

Postby jerrah » Mon Jul 11, 2011 4:43 pm

The Yaris does audibly knock on 91 unless the average blend in every servo I have visited is subpar.

My 'average' 91 and Shell 94 e10 has been randomly selected from city and country locations across NSW and QLD with the repeated economy results.
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Re: NB8 91 or 95 ron fuel?

Postby NitroDann » Mon Jul 11, 2011 5:20 pm

Yaris all have knock sensors, so whether your hearing knock or not, its bth pulling timing, and losing power due to knock.

Remember that factory knock control has a auto control limit, just like the degree of freedom you can choose to give your ecu over closed loop running.

So it may need 10 degrees pulled at MBT to stop knock, but it is only allowed a 3 degree retard by the ecus software.

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Re: NB8 91 or 95 ron fuel?

Postby Bizi » Mon Jul 11, 2011 5:42 pm

samx5 wrote:The first thing every noob gets told is to advance the timing to 14 degrees, so chances are unless you bought your brand new its been done. If it has you will have to run on 95 or 98. This is a part of what makes this question dubious, as unless youve checked the timing who knows what fuel you should use?

Dann

Yes, but mine's an NB8a which is harder to do the timing advance on than an NA6 for example. Agree, the timing test will clear things up a bit.[/quote]

Wade (previous owner of my Clubman): is the timing advanced on this car?

--
Since consensus is that any fuel 91+ is OK but 94/95RON is the sweet spot for slightly modded MX5s, where in Northern Sydney has the best deals and highest octane?

I prefer BP and use Normanhurst but it's not the cheapest but is always pretty good and I always leave there happy.

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Re: NB8 91 or 95 ron fuel?

Postby NitroDann » Mon Jul 11, 2011 5:51 pm

Will I...Will I...

Yeah ok.

Go to united and run e85 at $1.10/L and 110 Octane like a BOSS! :twisted: :twisted:

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Re: NB8 91 or 95 ron fuel?

Postby Locutus » Mon Jul 11, 2011 9:36 pm

jerrah, our yaris was from one of the first batches of the new (pre-facelift) shape to land in the country, and there is no mention of E10 on it anywhere. i was driving it before the govt decided to force servos to sell E10. good to see that our experiences have some consistency!

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jerrah
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Re: NB8 91 or 95 ron fuel?

Postby jerrah » Tue Jul 12, 2011 10:43 am

I'd run e85 if I knew I could easily pull into a servo and get it without having to drive to the other side of town.

My Yaris is a 2007 and has the e10 stickers. Benefit of 94RON e10 is that it's cheaper than 91 at the pump AND you get the increased distance to the tank!

91 e10 seems like lose lose so Shell gets my business.
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Re: NB8 91 or 95 ron fuel?

Postby 93_Clubman » Tue Jul 12, 2011 12:40 pm

samx5 wrote:
The first thing every noob gets told is to advance the timing to 14 degrees, so chances are unless you bought your brand new its been done. If it has you will have to run on 95 or 98. This is a part of what makes this question dubious, as unless youve checked the timing who knows what fuel you should use?

Yes, but mine's an NB8a which is harder to do the timing advance on than an NA6 for example. Agree, the timing test will clear things up a bit.

Hey samx5, did you eventually answer your question in this:
viewtopic.php?f=29&t=30568

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Re: NB8 91 or 95 ron fuel?

Postby Mr Morlock » Tue Jul 12, 2011 1:35 pm

Jerrah- E10 is cheaper but gets less l/100km- see the Drive report.

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Re: NB8 91 or 95 ron fuel?

Postby jerrah » Tue Jul 12, 2011 1:46 pm

Mr Morlock wrote:Jerrah- E10 is cheaper but gets less l/100km- see the Drive report.

Which fuels are you comparing? 91 unleaded to 91 e10 or 91 unleaded to 94 e10?

I've done repeated testing that 94RON e10 outperforms 91RON unleaded in MY applications. And as I reported above Shell 94 e10 is cheaper than 91RON unleaded.

e10 isn't really a 'fuel' rather than just an ethanol content indication.
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Re: NB8 91 or 95 ron fuel?

Postby Locutus » Tue Jul 12, 2011 2:48 pm

Mr Morlock wrote:I think some just ignore previous posts.
:roll: :roll: :roll:

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Re: NB8 91 or 95 ron fuel?

Postby NitroDann » Tue Jul 12, 2011 2:58 pm

Yeah Locutus Im with you....

Didn't I explain this fully or do people think im talking out my ass? :D

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.


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