premium v regular unleaded

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Re: premium v regular unleaded

Post by anchorman » Sat Jun 15, 2019 3:30 am

March wrote:
Fri Jun 14, 2019 4:30 pm
Take a look at the PDF attachments. Ethanol in regular petrol will corrode the engine. Having read this I use premium at least every 3 tanks. In my MX5 I use it in every tank.

ethanol 2.pdfethanol 1.pdf
Very interesting. Thanks.
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Re: premium v regular unleaded

Post by Idavies999 » Sat Jun 15, 2019 5:27 pm

What sort of average MPG are people getting from the 2.0L petrol, either on normal or super unleaded. I’m curious to know.
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Re: premium v regular unleaded

Post by HouseSpider » Sat Jun 15, 2019 9:37 pm

From what I see from various posts it can vary dramatically. Some people can't seem to get more that 40mpg, some over 50mpg.
It will obviously depend alot on how you drive the car and the nature of the roads and terrain in your locale.
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50ish mpg

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Re: premium v regular unleaded

Post by clawhn » Sun Jun 16, 2019 11:07 am

Bought my CX3 2.0 manual new in January. Covered 3k miles since and averaged 39.8 mpg . Mainly town, shortish trips and up / down welsh mountains, so I consider that to be good economy. Long trips give me around 50 mpg.
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Re: premium v regular unleaded

Post by Mrbluesky » Fri Jul 05, 2019 4:41 pm

I only ever use 95 regular petrol all the time and get 42.9 mpg as a long term average, my usual journey distance is probably about 20 miles with an occasional 50 mile run.

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Re: premium v regular unleaded

Post by santa » Sat Jul 06, 2019 5:33 am

I tried a few tankfull of a new 100 octane we have here in Denmark.
There was a noticable difference but not so much as to justify the 10% higher price.
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Re: premium v regular unleaded

Post by Paul97 » Sat Jul 06, 2019 1:49 pm

I'm using Tesco Momentum with a 50/50 spilt motorway and town and get 48mpg, well pleased. On a recent trip to Kent from the North East we averaged 50.4 😁

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Re: premium v regular unleaded

Post by anchorman » Sun Jul 07, 2019 4:06 pm

bloodline wrote:
Wed Jul 12, 2017 10:14 am
If you read about how the Skyactive-G engine works, it runs at a higher compression ratio than a regular petrol engine (closer to that of a diesel). In a normal petrol engine to achieve such high compression ratios, one would need to use a higher octane rated fuel (the expensive stuff), but Mazda have carefully timed the valves to intake a small amount of exhaust gas during the intake stroke (and I imagine careful timing of the direct fuel injection during the cycle), which retards the ignition of the fuel, in effect increasing the octane rating!

It's very clever stuff, only possible with powerful engine management computers.

-edit- So higher octane fuel is very unlikely to make any difference to performance, and on an engine under 5 years old, any detergent fuel additives are unlikely to offer the engine much.
You were doing ever so well until the last sentence. The detergents make a big difference.
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Re: premium v regular unleaded

Post by RichR » Tue Jul 09, 2019 4:25 pm

I've been using Asda normal unleaded (95RON), just because it's nearest to my place of work, occasionally using Texaco 95, and on my 26 mile commute via the A2, Dartford Crossing and A13 regularly get between 45 and 51 mpg according to the 'mpg this trip' read out (got 54 mpg this morning!). Went to France with roof bars and two bikes on top on 95RON and was getting c.43 mpg while running around 65mph, and up to 50 mpg with just the bars and no bikes Filled up in France with 98RON just before coming home and mpg performance was about the same although the car did seem to be smoother. So I can't see a financial advantage in using a higher octane.
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Re: premium v regular unleaded

Post by March » Tue Jul 09, 2019 6:25 pm

It's not just about mpg. Ethanol corrodes engines.

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