Tesco Momentum vs. Shell V-Power

[wiggles]

I just use standard fuel in mine... Cost enough as it is spent £68 at shell yesterday

[tekkendp]

Okay - here's the follow-up.

Drove the car until empty. Full tank of Tesco Momentun (no pre-mixing this tme). Did motorway run. Now the car starts (hot/cold luke-warm, whatever) perfectly fine (quick minimal crank), like it did before the V-Power fill-up. It's been spot on all week.

So, the best I can say on this, Shell V-Power gives my car a serious case of Deli-belly. Wonder if this a hi-power (231bhp) thing? Still going to do the TLC treatment. Oh... the paranoia ... I mean joys of RX-8 ownership.

[PeteH]

Definitely not a 231 thing. Mine runs perfectly on V-Power, as do many others I believe.

[Dazza44]

Mine to

Sent from my GT-I9505 using Tapatalk

[nightfire10]

Okay - here's the follow-up.

Drove the car until empty. Full tank of Tesco Momentun (no pre-mixing this tme). Did motorway run. Now the car starts (hot/cold luke-warm, whatever) perfectly fine (quick minimal crank), like it did before the V-Power fill-up. It's been spot on all week.

So, the best I can say on this, Shell V-Power gives my car a serious case of Deli-belly. Wonder if this a hi-power (231bhp) thing? Still going to do the TLC treatment. Oh... the paranoia ... I mean joys of RX-8 ownership.

I use v power most of the time

[Rotary Potato]

Another 231 that loves V-Power.

[acegeezer]

It doesn't make any difference really, I tested V Power for a good few months before returning to the normal 95ron having achieved no perceived benefits from the higher octane fuel in my R3

[Lemon]

they seem to be very picky when it comes to their preferred fuel, mine absolutely hated momentum when i filled up with it but has run faultlessly on sainsbury's super.

[warpc0il]

Mine hates Tesco 95, is okay on Maxol 95 and noticeably smoother on Sainsbury's Super

[akhan48]

I’ve always used V Power and nothing else, but all your comments above makes me want to experiment in case there’s another fuel my car likes better!

[GreySilver Beast]

My first RX-8 LP was happy on 95 Ron then they seem to change it and the car then no longer liked 95 Ron ,then switched to 97 Ron Super Unleaded and then the car ran smoothly after that

The RX-8 R3 was very happy on 95 Ron and the only time it got treated to Super Unleaded was when I was doing a Track Day

[acegeezer]

Maybe the R3 is more tolerant with any of the fuels

[delta0]

The R3 has 2 knock sensors (1 per rotor) whereas the S1 has 1 knock sensor. Could be a contributor?

[Lemon]

something else worth noting i see a marked increase in range when running on sainsbury's super as opposed to 95.

[manuRx8]

Ethanol defiantly causes problems with classic cars and bike, as the materials used in the fuel lines, pumps, seals, carbs etc, was never designed to be ethanol resistant and, in most cases it isn't, even at the low levels we are now starting to see in UK pump fuels.

The RX8 was designed and most were manufactured, before ethanol became a significant factor in the markets in which the car was sold. There is no mention of ethanol resistance in any of the original or subsequently released service publications. However, this is also true for most cars produced in the early 2000's and that's why there's a limit to the ethanol permitted to be added to standard pump fuels. We may start to see some garages offering higher-ethanol fuels as an alternative, as they do in the US, though this can cause all sorts of miss-fuelling issues and confusion.

I disagree with this statement: several reports published by Mazda indicate that in Europe, all gasoline models marketed as of 2002 are compatible with 95 E10 gasoline.

In fact, in some countries, mixtures between E5 and E25 are already being used (Germany, Sweden, USA, Canada, Australia, etc.) and in others, small quantities are added as an additive to increase the octane rating, without indicating anything to the consumer.

In the user manual, in the part "Fuel Requirements" you can find the paragraph: "Your vehicle can only use oxygenated fuels containing no more than 10% ethanol by volume. Damage to your vehicle may occur when ethanol exceeds this
recommendation, or if the gasoline contains any methanol. "

Reviewing multiple articles and technical studies, I have seen that everyone agrees that consumption increases somewhat (by 3% for an E10) but also all agree that it has some other advantages:

• Improve the octane rating of gasoline (improvement in response in casualties is noted)

• Reduces the variability cycle to cycle (more regular operation, especially in high)

• Improves the volumetric efficiency of the engine, reducing the temperature in the intake manifold (in our case it would help the gasoline to cool the chambers).

• Reduces carbon deposits ("dissolves" slowly) and prevents new ones from forming.

• Reduces pollution (especially CO and HC)

• Eliminates water from gasoline and deposits: it makes it soluble in gasoline, preventing clogged ducts and injectors, burning eventually with gasoline.

In fact I am using an ethanol mixture between 7% and 10% (handmade) I have already done about 9000 km with that mixture and the increase in consumption is lower than expected (1.6%). About the advantages mentioned above, I can confirm some. Others would need data, but I think it's working.

What I can confirm is the last one (make the water soluble in gasoline) since in the mix I have also included a part of distilled water (120ml per tank) looking for the improvements of the water injection and until now, I have not found any problem.

It is true that the improvements I notice are subjective, but what I can affirm is that I have not detected any problems.

[warpc0il]

several reports published by Mazda indicate that in Europe, all gasoline models marketed as of 2002 are compatible with 95 E10 gasoline.

Please provide links to these reports, as I approached Mazda UK in 2008, on behalf of the OC, and they advised that no UK-registered RX8 to that date was compatible with E10 fuel.

They did suggest that the "new RX8" aka R3, would be compatible.

[bigpete8]

Not saying I like the idea, as owned an MGB around the time of the move to unleaded and well aware of issues with fuel lines and valve seats that could cause but...

What is E10 fuel and how could it affect you:
https://www.rac.co.uk/drive/advice/emis ... ffect-you/

Compatibility list:
https://www.acea.be/uploads/publication ... BILITY.pdf
shows Mazda:E10 petrol is cleared for use in all models with petrol engines introduced in and from the year 2002 - RX-8: SE.

who they are:
https://www.acea.be/

and worth a quick look:
http://www.fuel-identifiers.eu/docs/QA-consumers-EN.pdf

[New Duke]

Maybe Mazda wouldn't say that the S1 was compatible with E10 because they never tested it? Given the date of the design process and how far away E10 adoption was back then. Whereas by 2008 for the S2 E10 was something they couldn't ignore. Could just have been a lack of testing so easier to say to customers it isn't compatible and save testing an old model.

Either way, am glad I got an R3. I'll take being able to refuel over your better gearbox

[manuRx8]

This is a copy of the aforementioned page of the USA User Manual. You can check in yours, to see what they say.


I do not have the original documents, only references to them from various Rx8 forums and others. I hope they serve you.
http://www.rx8france.com/forum/viewtopi ... 20&t=14878
https://www.rx8club.com/australia-new-z ... 10-164985/
https://www.rx8club.com/australia-new-z ... uel-73153/
http://www.maizeaustralia.com.au/events ... endell.pdf (See the last pages)
...

[Clive]

Race Car is mapped for V Power with Lucas octain booster which is Rotary friendly and not oxygenated unlike many, but I always used this in the road RX-8 especially when going on track.

But more importantly I have been told that V Power has the lowest ethanol content of any fuel in the UK

[CTID]

With regards use of Ethanol my wife had a Focus 1.8 dual fuel on a 56 plate that was set to work for either normal or up to E85 fuel (not choice just happened to be the right age/model/price). That was a 2006 and the manual made mention that Ethanol had been used in fuels in low concentration for many years. As per manuRx8's post I'd be surprised if there wasn't consideration for low percentages of ethanol in fuel from before the RX-8 was interoduced. We don't still have it but there's probably copies of owner manuals around online somewhere.

The only mention of changes verse the normal 1.8 was that certain parts were hardened more than normal which from memory (metalurgy lectures 25 years ago) would improve their wear properties which makes sense in the context of potentially stripping lubricants mentioned earlier.

On thing with bioethanol however, no matter if it's E10 or much higher percentage is that the meterials it's produced from are largely food crops. Such is people's stupidity that in a world with people starving to death someone feels the need to use food to power cars.

[warpc0il]

The UK Owners Manual page is different..

UK fuel.jpg

we know that the PCM firmware for UK, JDM and USA are also all different.

That page is from the 2005 Edition and IIRC EN228 was updated in 2012 to include a maximum of 5% Ethanol

[PeteH]

Some sums, for reference.

Compared to petrol (I'm assuming pure octane) pure ethanol has:
- 12% higher density
- 30% lower calorific value
- 40% lower stoichiometric ratio (9:1 rather than 14.7:1)
- 113 octane rating
- 12% less carbon dioxide emissions

These values mean that your tank of pure ethanol will:
- take you only 68% of the distance that petrol will take you. (Or have 32% worse mpg, if you prefer. If you get 20mpg on petrol you will get 13.6mpg on pure ethanol)
- Produce 18% more power.
- Require a fuel pump and injectors that can flow 49% more fuel.
- Will permit more aggressive compression ratio / boost / timing, further increasing the potential power.

When going for E85 the most important design change is to specify a high flow fuel pump, and larger injectors, and then tune the fuel flow tables appropriately. If you don't then the mixture goes lean at high speeds and loads, then things go bang....

[delta0]

E10 is EN 228 compliant as far as I am aware.

[phoenix11]

V-Power currently £6.75 per Gallon!
Anyone higher?
I use Tesco Momentum