Maxol E5 - where's the catch?

MarkN

The local Maxol to me had signs outside for E5 today and as it happened I had run the car almost dry to see what I would get from a full tank.

Filled it up and they have little cardboard signs on the pumps explaining what it is. First thing I noticed was that it was 114c a litre - same price as normal unleaded.

So when I went in to pay, they have more leaflets at the till and I brought it with me. It clearly says that in tests, the average octane rating of E5 is 99.2 so it's easily going to be 98.

I'm just wondering, mainly due to the price, where is the catch!? Or is it a case of E5 was made to be better for the environment and it just is an added bonus that the rating is around 99 octane and they are not charging for the fact?

It says all Maxols will have it shortly.

bennyx_o

Basically, it's 95% unleaded and 5% bio fuel (ethanol IIRC) It's not levied like normal 98ron as it's classed as a Bio Fuel. It's supposed to be better for the environment, too, so while you're getting the best out of your car, you're doing the trees a favor too.

bushy...

I suppose it saves them money somewhere/how , happy side effect is the "e" bit is high octane, so means less additives to make fuel that suits nice highly strung engines
Lead is good though http://www.racefuels.com.au/fuelsDetail.asp?ID=11
gram and a half in every litre , like that chocolate ad...

colm_mcm

I filled mine with it last week, but it'll take a while for the ECU to recognise that I'm using proper petrol now!

E92

ECU only reprogrammes the engine if you use a fuel lower than the reecommended octane rating of your car(and unless we're talking about a high performance and/or direct injection car), it makes very little difference. If you use a higher octane rating than the recommended it makes no difference whatsoever.

But as E5 if perfectly acceptable to BMW and to every other car made in the past 10-15 years and will reduce the car's net CO2 emissions by around 4%, whats not to like about it?

pete4130

almost all unleaded fuel you get has some ethanol in, sometimes up to 15%.
For more info check www.greenfuels.co.uk

ethanol burns hotter and has a higher octane (but less mpg!). Maxol and ford have a partnership for FFV's (flexi fuel vehicles) that run on E85 (85 ethanol, 15% unleaded). any petrol car made after 1990 can run it pretty much, a few mods to ruber hosing so the ethanol doesnt rot it away and a chip to regulate how much fuel and the timing of the spark and your running. sipposedly an in crease in performance with higher octane?

80% of new cars in brazil run on E85 (or any mixture of ethanol and unleaded). SAAB also do a FFV car too. When you buy a new car here the government gives you a 50% rebate on your VRT, which isn't enough to encourage the use of E85 tbh. The good thing with E85 is it produces 70-80% less co2 and as the ethanol is roduced by crops, this is offset by the co2 the crop takes in when growing. It beats me why E85 isnt more popular, its cheaper, cleaner and removes out reliance on oil as well as keeping jobs going here (our ethanol is produced by a dairy farm in cork!).

I've done alot of research into the use of ethanol as I'm thinking of converting my car (no govt. grants or tax relief for doing that) so hence I know some of the useless facts mentioned above!

colm_mcm

E92 wrote: »

ECU only reprogrammes the engine if you use a fuel lower than the reecommended octane rating of your car(and unless we're talking about a high performance and/or direct injection car), it makes very little difference.

The car is a japanese domestic market coupe. think they're supposed to run on 100 RON.

Del2005

MarkN wrote: »

The local Maxol to me had signs outside for E5 today and as it happened I had run the car almost dry to see what I would get from a full tank.

Filled it up and they have little cardboard signs on the pumps explaining what it is. First thing I noticed was that it was 114c a litre - same price as normal unleaded.

So when I went in to pay, they have more leaflets at the till and I brought it with me. It clearly says that in tests, the average octane rating of E5 is 99.2 so it's easily going to be 98.

I'm just wondering, mainly due to the price, where is the catch!? Or is it a case of E5 was made to be better for the environment and it just is an added bonus that the rating is around 99 octane and they are not charging for the fact?

It says all Maxols will have it shortly.

The EU wants all petrol sold in Europe to be E10 soon, the way they see it is that it's better to have 10% of the whole fleet on "enviromentally friendly" fuel then a much smaller % on E85.

The reason why I've used the "enviromentally friendly" is because of all the damage being done in the tropics plating palm oil plants and also the fact that some of the bio fuels being produced are claimed to have more CO2 output and cause damage to the enviroment in other ways

http://www.boards.ie/vbulletin/showthread.php?t=2055167171

dcGT

So, I've two questions: -

1. Can this E5 stuff be used in any petrol car or are there certain restrictions? If so, what are they?

2. Will it increase the performance of a car designed to run on 98 RON (or higher) that's currently running on 95? If so, have people experienced this performance increase first hand?

Cheers,

DC.

TommyT

1. Apparently E5 can be used on any car that runs on unleaded fuel but do not get this confused with E85 which can only be used on cars that have been modified to run on it.

2. I have been using E5 for a couple of weeks and cannot notice any performance increase.

JHMEG

colm_mcm wrote: »

I filled mine with it last week, but it'll take a while for the ECU to recognise that I'm using proper petrol now!

This should be almost instant as far as I know. Like as soon as you drive off the forecourt. The knock sensor should notice the difference and retard/advance timing instantly. It doesn't have to "learn" anything... my car doesn't take any time to learn when there's 95 or 98 in it.

JDM cars are not mapped per se to run on 100RON. They run a map (a lookup table) like all cars do, and timing is altered depending on the knock sensor inputs. But the map remains the same. The performance difference between octane ratings is no more profound with a JDM car than it is with a Euro car etc.

dcGT

TommyT wrote: »

2. I have been using E5 for a couple of weeks and cannot notice any performance increase.

Thanks TommyT. Is the car in question one that is designed for 98 RON?

Cheers,

DC.

Anan1

I filled with E5 last week and noticed an immediate difference. (in a car that takes 98)

Anan1

One other thing - I would expect fuel consumption to be marginally higher on E5, due to its slightly lower calorific value.

omega man

Anan1 wrote: »

I filled with E5 last week and noticed an immediate difference. (in a car that takes 98)

Deffo agree for a 98Ron recommended car.

dcGT

E92 wrote: »

ECU only reprogrammes the engine if you use a fuel lower than the reecommended octane rating of your car(and unless we're talking about a high performance and/or direct injection car), it makes very little difference. If you use a higher octane rating than the recommended it makes no difference whatsoever.

So if the ECU does not 'adjust' when a higher octane fuel is introduced, why do some people report better performance? I assume these people are the ones with 'high performance' cars? Just trying to understand this.

Cheers,

DC.

Anan1

dcGT wrote: »

So if the ECU does not 'adjust' when a higher octane fuel is introduced, why do some people report better performance? I assume these people are the ones with 'high performance' cars? Just trying to understand this.

Cheers,

DC.

Because their recommended octane rating is higher. A car that's supposed to get 98 won't be so happy on 95. A car that's set up for 95 will be fine on 95.

dcGT

Anan1 wrote: »

Because their recommended octane rating is higher. A car that's supposed to get 98 won't be so happy on 95. A car that's set up for 95 will be fine on 95.

Ah ok. I misunderstood E92's post. It suggested to me that the ECU will not reprogram if you begin using 98RON in a 98RON engine that had been using 95RON. So here's the scenario: -

98RON Engine
98RON Fuel - Fine
95RON Fuel - ECU adjusts (as fuel is lower than recommended rating)
98RON Fuel - ECU already set for 95RON - Does the ECU adjust again for the higher rating for which the engine was designed? I assume this is the case?

Cheers,

DC

Anan1

dcGT wrote: »

98RON Fuel - ECU already set for 95RON - Does the ECU adjust again for the higher rating for which the engine was designed? I assume this is the case?

Cheers,

DC

Yes. The engine always tries to adjust up to the rating for which it was designed, ie a 95 engine will try to adjust up to 95 and a 98 engine will try to adjust up to 98.

MarkN

Hard enough to tell how this changed my car because I only did about 4kms since filling up but when I opened the tank flap it also said it could be run on 91 unleaded - that must be fun :eek:

Mayshine

The S2000 likes it - Its mapped for 98 so it should - Its taken a couple of fills but the difference is mostly in engine smoothness and a little more pull from 6k-9k

I'll be sticking with it for sure

whippet

The GTi is due a fill tonight .. might pop a tank of E5 in to it and see how it goes .. as far as I know it is set for 98ron.

JHMEG

As I said earlier in response to colm's post, there is no such thing as a car being mapped for 98RON. Normal cars will have one map which is used for all octance ratings from the lowest (probably about 88) up to the highest (105 maybe) that the makers reckoned the car would encounter in normal life.

The knock sensor determines the grade of petrol and will alter ignition timing to suit. Higher octane suffers from less pre-ignition than the cheaper stuff so the ECU can set the timing more precisely, using different parts of the map. You may see more performance, you may not.

To say a car is mapped for 98 means it will not run well, if at all, on anything else.

Mayshine

fair enough about the maps, however why would their be a big sticker on the fuel flap saying 98 RON min. I presume its because the compression rationis high and it needs a more knock resistant grade of fuel

As far as I am aware there is a default ignition map that sets the timing based on the engine revs / load has the appropriate timing adjustments.

For most cars these are set optimal timings for 95 RON with the ECU retarding these timings when it senses knock.
For other cars, these timing are for 98 RON (mine for example). This is dependnent on different factors, e.g. comp ratio, boost etc.

When I drive mine on 95 the engine retards the timing to some degree from the value in the open loop map until the knock is reduced to an acceptable level

So surely there is only one map, albeit one that can be adjusted dynamically (downwards)

JHMEG

Yes, there is only one map, but several "routes" can be taken thru that map. Best analogy I can give. But that map will cover a lot of different grades.

A lot of high performance cars will say 98 as it's the best there is, and they will perform best on it, as will most cars. In the US the S2000 will say 95 as it's the best there is there.

To answer the OP's question, as far as I can see the only thing about E5 that *might* be a slight problem is that water will mix with alcohol, and it is possible atmospheric moisture would be absorbed in your fuel tank. This can be a serious problem with E85.

E92

What I meant(though it is clear some people didn't understand fully understand my explanation, so sorry about that) is that the ECU reprogrammes the engine management to compensate for using a fuel with a lower RON number than the recommended one.

This usually means a small reduction in power, often so small you couldn't tell e.g BMW 330i E46 on 98 RON produces 231 bhp, on 95 RON it produces 221 bhp.

If you use petrol with a higher RON number than the recommended one, it makes no difference whatsoever to the performance of the car. The ECU doesn't remap the engine if you use a petrol with a higher RON number than is necessary.

In other words, unless you own a highly tuned up car like say an S2000 with its 118.5 bhp per litre, which is a huge amount of bhp per litre, or a car with direct injection like all the new BMWs, it will make practicaly no difference to the performance of the car using 95 RON on a car designed for 98 RON.

Basically unless you have a high performance and/or direct injection car, designed for 98 RON or not, buying Super Unleaded or 98 RON fuel is throwing money down the toilet.

And if you use a fuel with a higher RON than the recommended one the ECU doesn't reprogramme the engine for that fractiobnal increase in power, so you really don't need 98 RON in a car designed for 95 RON.

colm_mcm

So if my car is set up for 100RON and I'm using 95, this means I'm down in power doesn't it.
So by using higher octane fuel I'm getting more power than I would on 95?

E92

Well to quote myself::D

E92 wrote:

unless you own a highly tuned up car like say an S2000 with its 118.5 bhp per litre, which is a huge amount of bhp per litre, or a car with direct injection like all the new BMWs, it will make practicaly no difference to the performance of the car using 95 RON on a car designed for 98 RON.

Basically unless you have a high performance and/or direct injection car, designed for 98 RON or not, buying Super Unleaded or 98 RON fuel is throwing money down the toilet.

And yes the higher the recommended RON is, then obviously using 95 will have more of an effect on performance, but the point I was trying to make is that in the vast majority of cars the difference in power is so small that there will be little if any difference.

colm_mcm

I wonder how much extra oomph it will give, time will tell !

Tanabe

colm_mcm wrote: »

I wonder how much extra oomph it will give, time will tell !

What JDM coupe are you drivin'?

FTO okay, keep using the E5 & let us know if you feel any difference;)

E92

colm_mcm wrote: »

I wonder how much extra oomph it will give, time will tell !

You should already know the answer if you have started using it!

I think it was JHMEG who correctly said that the engine management adjusts straight away.

Elessar

I'd like to try it on my 320ci but according to BMW they don't recommend it. I still cant believe you cant buy actual 98RON fuel in this country.

colm_mcm

E92 wrote: »

You should already know the answer if you have started using it!

I think it was JHMEG who correctly said that the engine management adjusts straight away.

On the GPX it adjusts after around 100km or when you take the battery out I heard.

Henry Ford III

I seem to remember on the Focus ST that 225bhp was available on 95 u/l, and this rose to 237bhp on Optimax (98 u/l).

About a 5% difference. Hardly worth the bother and expense.

richie_rvf

Henry Ford III
I seem to remember on the Focus ST that 225bhp was available on 95 u/l, and this rose to 237bhp on Optimax (98 u/l).

About a 5% difference. Hardly worth the bother and expense.

Isn't the fuel supposed to be the same price? I thought that Maxol have replaced their u/l with E5.


Elessar
I'd like to try it on my 320ci but according to BMW they don't recommend it. I still cant believe you cant buy actual 98RON fuel in this country.

I have used it twice now in my BMW, did not notice any difference in performance but the car certainly runs smoother and from very low rpm seems to pull slightly better, not in power but smoother - if you know what I mean.

Richie.

Henry Ford III

Some confusion here Richie.

Optimax was 99 RON, but has been withdrawn. Replaced by V Power, which appears to be 99 RON in the UK, but only 95RON here.

richie_rvf

Henry Ford III wrote: »

Some confusion here Richie.

Optimax was 99 RON, but has been withdrawn. Replaced by V Power, which appears to be 99 RON in the UK, but only 95RON here.

What I meant was the price of fuel at Maxol garages, I thought they had just replaced their unleaded with E5 so the price should be the same.

Yeah, I knew that about Shell, I used to go across the border to fill up - never made any difference - except in my head :rolleyes:

JHMEG

colm_mcm wrote: »

On the GPX it adjusts after around 100km or when you take the battery out I heard.

It shouldn't do. It should be pretty instant. If you have the tiptronic gearbox that takes a while to adjust to your driving style (eg if you've just bought the car), or disconnect the battery and it will learn as soon as you drive it next.

Also I think that lower power cars will notice an improvement more so than higher power. I know when I put 98 in my 75bhp 1.3 (back when 98 was 49p a litre!) there was a huge difference. As E92 pointed out a difference between 221bhp and 231bhp may not be noticeable, especially if it is a heavy car.

Flaccus

Isn't it calorific content that matters for power output and not just RON. As the E5 calorific content is 30.51 MJ/Litre versus normal 95 unleaded of 31 Mj/Litre won't the power output be the same as 95RON, as opposed to true 98RON which I assume would have a higher calorific content. And if you are using a car setup for 98RON, wouldn't the ECU adapt after a couple of hundred miles and burn through E5 a lot quicker then 95RON ?

Anan1

Flaccus wrote: »

Isn't it calorific content that matters for power output and not just RON. As the E5 calorific content is 30.51 MJ/Litre versus normal 95 unleaded of 31 Mj/Litre won't the power output be the same as 95RON, as opposed to true 98RON which I assume would have a higher calorific content. And if you are using a car setup for 98RON, wouldn't the ECU adapt after a couple of hundred miles and burn through E5 a lot quicker then 95RON ?

I would have thought that the power output would be as per 99RON, but that the fuel consumption would be higher as a result of the lower calorific content. Isn't that what happens with E85?

TychoCaine

Flaccus wrote: »

Isn't it calorific content that matters for power output and not just RON. As the E5 calorific content is 30.51 MJ/Litre versus normal 95 unleaded of 31 Mj/Litre won't the power output be the same as 95RON, as opposed to true 98RON which I assume would have a higher calorific content. And if you are using a car setup for 98RON, wouldn't the ECU adapt after a couple of hundred miles and burn through E5 a lot quicker then 95RON ?

He's right.... The octane rating is a measure of a fuel's knock* resistance. It has nothing to do with the amount of power you get out of it. While a given fuel's power increases in proportion to it's octane rating, different types of fuel don't correspond. Ethanol only has 2/3 the power of petrol (21Mj/L Vs 31Mj/L), even though it's more knock resistant.

Because the mixture is more knock resistant than normal 95RON, the engine can run more aggressive timing, and generate more power for a given quantity of fuel. This compensates for the actual lower energy content of the mixture, but no more, even on JDM cars. The only real benefit is that the CO2 emissions are 3.4% lower than 95RON.

* For those that don't know, Knocking/Pinking/Pre-Detonation is petrol's propensity to spontaneously ignite when compressed (like diesel does), before the spark plug lights it. A high compression engine requires a high octane fuel to run correctly. Otherwise the petrol ignites itself before the piston gets to the top of the cylinder, which would interrupt the smooth rotation of the engine components, causing a "knock".

Flaccus

Octane rating only reflects the ability of unburnt end gasses to resist spontaneous autoignition. When this happens you get a pressure rise as both the spark flame front and ignited end gas are expanding which causes an early pressure peak that is reponsible for the oscilliations which create the so called knocking noise. The Octane rating or antiknock index just measures the ability of these gases to ignite. Higher Octane rating means more efficiency and so potentially more power, but if the calories per litre are substantially less with E5 compared to proper 98RON I would doubt you get more power at all.


<edit>Didn't see above post</edit>

dcGT

Flaccus wrote: »

Octane rating only reflects the ability of unburnt end gasses to resist spontaneous autoignition. When this happens you get a pressure rise as both the spark flame front and ignited end gas are expanding which causes an early pressure peak that is reponsible for the oscilliations which create the so called knocking noise. The Octane rating or antiknock index just measures the ability of these gases to ignite. Higher Octane rating means more efficiency and so potentially more power, but if the calories per litre are substantially less with E5 compared to proper 98RON I would doubt you get more power at all.


<edit>Didn't see above post</edit>

Interesting. So is this stuff a placebo of sorts?

DC.

TychoCaine

Anan1 wrote: »

I would have thought that the power output would be as per 99RON, but that the fuel consumption would be higher as a result of the lower calorific content. Isn't that what happens with E85?

In a given engine you get a certain amount of power per calorie used. You put a fixed quantity of energy into the engine in the form of fuel, you'll get the same out the other end at the flywheel, less the inefficiencies (heat, noise etc.) in the engine. You have to put more energy in to get more energy out.

If we were to forget about ignition timing for a second here, your ECU would decide whether to consume fuel at a higher rate to maintain horsepower, or consume fuel at the normal rate and produce less horsepower. In the latter scenario you'd probably override it anyway by being slightly heavier with your right foot. What will happen in reality is that the ECU will detect 99RON fuel and fuel at the normal rate but change the ignition timing (because it can allow it to get more compressed before having to ignite it) to be more efficient. This will bring the BHP back up in line with normal 95RON, and maintain normal levels of fuel consumption.

Take a look at the Maxol website here. Don't you think they'd be shouting it from the rooftops if they had a fuel they could sell for the same price as 95RON that would give more power or economy?

TychoCaine

dcGT wrote: »

Interesting. So is this stuff a placebo of sorts?

DC.

Not quite. It won't make a difference to performance or efficiency, but it's good for the environment because it lowers CO2 emissions by 3.4%.

Flaccus

I've been using it on my Octavia vRS for a while (local station is on maxols e5 list) and didn't even cop it.

Max_Damage

I haven't read this entire thread, so I don't know if this has been brought up, but meh...

Given that ethanol has approx. 33% less energy per same unit volume than petrol, then this E5 stuff that Maxol are selling will have slightly less energy than unleaded petrol. That's provided they didn't put some additives to the fuel.

Flaccus

Yeah...mentioned in a post above in detail by Tycho

Anan1

TychoCaine wrote: »

In a given engine you get a certain amount of power per calorie used. You put a fixed quantity of energy into the engine in the form of fuel, you'll get the same out the other end at the flywheel, less the inefficiencies (heat, noise etc.) in the engine. You have to put more energy in to get more energy out.

If we were to forget about ignition timing for a second here, your ECU would decide whether to consume fuel at a higher rate to maintain horsepower, or consume fuel at the normal rate and produce less horsepower. In the latter scenario you'd probably override it anyway by being slightly heavier with your right foot. What will happen in reality is that the ECU will detect 99RON fuel and fuel at the normal rate but change the ignition timing (because it can allow it to get more compressed before having to ignite it) to be more efficient. This will bring the BHP back up in line with normal 95RON, and maintain normal levels of fuel consumption.

Take a look at the Maxol website here. Don't you think they'd be shouting it from the rooftops if they had a fuel they could sell for the same price as 95RON that would give more power or economy?

So what you're saying is that the lower calorific value of the fuel is compensated for by the fact that it can be burnt more efficiently because the ignition can run more advance? This makes sense for an engine that's set up for 98, ie one that will advance ignition timing when the fuel allows. What about most cars though, which are set up for 95? Won't they just get poorer economy with nothing to show for it?

TychoCaine

Anan1 wrote: »

So what you're saying is that the lower calorific value of the fuel is compensated for by the fact that it can be burnt more efficiently because the ignition can run more advance? This makes sense for an engine that's set up for 98, ie one that will advance ignition timing when the fuel allows. What about most cars though, which are set up for 95? Won't they just get poorer economy with nothing to show for it?

Even my old 1.4l Focus had a "98RON recommended" note in the manual, and I can't ever remember driving a car where 95RON was recommended. I'd have thought anything with electronic fuel injection and ignition would adapt just fine.

Spit62500

Flaccus wrote: »

I've been using it on my Octavia vRS for a while (local station is on maxols e5 list) and didn't even cop it.

Your local station may be on the list but not yet stock it. The Maxol in Newbridge is on the list for a few weeks but doesn't yet stock it. They have started to install a designated E85 pump (as of last weekend) so its on its way. The Maxol in Naas has it - you can tell because there are stickers proclaiming it on the pump.