"High-Octane Fuel" -Performance Con.

[gfunk]

Hi,

I, along with 9 other fortunate chemical engineers have been performing quite a number of tests with quite a lot of small engine cars recently, as well as high performance sports cars.

For contractual reasons, I can't provide car brands; but under all conditions, no performance betterment was experienced. Fuel will last slightly longer, due to higher efficiency detonation - but there is no performance advantage whatsoever. It was thought that performance-based usage of high-octane petrol was a major reason for customers purchasing it; but it would appear that this is only perceived performance, perhaps due to a smoother drive, due to less eratic engine operation. However, this smootheness incrase is only slight.

These results are also appropriate for this website, if that helps you perhaps understand one brand/model of the many cars tested!

Once published, there will of course be advisory terms stating that high octane petrol is definitely better for your engine; causes less wear on internal engine components. However, it is not a wise investment for any non-sports car, or non-rotary engines (ie: rotary engines are only utilised by a couple of Mazda models nowadays), unless you enjoy spending extra money for no particular reason.

Regards.

 

[Ed]

Hmm, "due to higher efficiency detonation" that makes no sense?

I always come across as being critical, but unless you wrote that very fast without thinking it either makes no sense or is ill-informed and not accurate.

 

[Low Rider]

I, along with 9 other fortunate chemical engineers

I find your credentials difficult to believe from that post, especially since, and thanks Ed, you mention something called "higher efficiency detonation". Something combustion engineers try to avoid...............

Not to blow my own trumpet but having 3 years fuel analysis experience with a well reputed laboratory I will quite happily say that your "apparent" research is both unfounded and flawed on may levels.

 

[Davey C]

in my oppinon they work well with turbo'd cars, (and N/A for that matter) mine runs "much" nicer with optimax in. im not saying it goes faster as i cannot prove it but i would say it definietly "feels" faster.

do you work for a pro high octane fuel company or and fuel company against higher octane fuel.

i would be interested to read your findings if that is possible and see all of the information you have gathered. should make very interesting reading

 

[gfunk]

I used that term purely because a number of teenage car owners in my area convert the operation of your bog-standard petrol engine to more simplistic terms.

I used the word 'detonation' for that reason, as - from my experience - people tend to misundersatnd how your typical petrol engine works. I may have a PhD in the matter, but most don't

Obviously it's better to go into much more (accurately worded) detail at times, but on a forum mainly comprised of under 21s, it's probably not as great an idea, as causing confusion is never a good idea!

 

[Davey C]

put it into more detail but with an idots guide in brackets then? i would beinterested to find out more about your findings ie driving conditions tested and 1 tank...2 tanks etc in a lab in the town, motorway, etc, any more info would be great

 

[gfunk]

It is certainly all perceived, but no doubt it is better for your engine-life, but with regular servicing this will override the need for high-octane fuel in your car I am sure.

I'm not allowed to mention who I work for, but rest-assured it's not for (or against!) any of the big 3 oil companies; it's simply for the advancement of engines. There is still much debate in the car-industry as to whether very highly-efficient dual-fuel petrol-engines, which use high-octane fuels, could be the future for our vehicle industry.

At the minute we can fine-tune an engine - albeit it a medium-sized city car - to get around 98mpg. This does utilise high-octane fuel, but is so efficient due to taking complete advantage of high-octane fuel properties.

If it helps, any car you see in the forecourt today has been pre-planned approximately 6 years ago. We are working on vehicles to be presented around 2012; as with all technology consumer-adoption is important. A very bad image of eco-efficient cars has been presented as very few manufacturers have actually dared to put their designs into prototypes. Why? Well it's a tough industry, and there's a lot of spying and stealing goes on.

Needless to say, I was just trying to point out you can save your money on high-octane fuel. Even with the FOIA, I can't provide PDFs for at least 5 years on anything I have studied. I sold my soul, but hopefully it will be for the better in six to eight years time!

You will find that most research companies do not conduct tests in open conditions; we use machines to simulate conditions, such as weather conditions, humidity, and friction available.

If it wasn't for contractual reasons, I could provide you plenty of figures to mull over. You may notice there is very little concise information out there regarding fuel - the big three oil companies ensured that most related test companies cannot publish information on different brands of petrol and detergent additives,as it could be viewed as anti-competative and render the test company liable.

I know it can be hard to appreciate, but whether you are roaming about town at 30mph, or going at 90mph on a motorway, normal 95o with standard detergents from your local supermarket will provide you with the same performance as the big brands' high-octane version.

 

[Ed]

normal 95o with standard detergents from your local supermarket will provide you with the same performance as the big brands' high-octane version.

Utter nonsense. Sorry but that simply is a stupid comment to say!!! If I ran some of the cars I map on 95 octane and tried to push for the same power I do on say 100+ octane they would go bang, and would end in a horrid mess of melted pistons and blown headgaskets.

It may be true to say that the lubrication and detergent properties of all pump fuels are just as effective, but it is certaintly not true to say they will all produce the same power.

 

[Low Rider]

I used that term purely because a number of teenage car owners in my area convert the operation of your bog-standard petrol engine to more simplistic terms.

I used the word 'detonation' for that reason, as - from my experience - people tend to misundersatnd how your typical petrol engine works. I may have a PhD in the matter, but most don't

Obviously it's better to go into much more (accurately worded) detail at times, but on a forum mainly comprised of under 21s, it's probably not as great an idea, as causing confusion is never a good idea!

I can assure you that there are many people on this forum who know plenty about combustion cycles, both CI and SI.

If most of this forum is under 21's and incapable of understanding anything you write, then you're wasting your time.

 

[Andrew]

I used the word 'detonation' for that reason, as - from my experience - people tend to misundersatnd how your typical petrol engine works. I may have a PhD in the matter, but most don't

Using the word detonation in place of combustion isn't simplification, it's incorrect. Anyone capable of understanding the word detonation would be fine with the word combustion - or if you wanted simple, you could have gone with "burning".

fuel will last slightly longer, due to higher efficiency detonation - but there is no performance advantage whatsoever

When you say "last longer", I presume you mean that the engine's thermal efficiency will be higher and hence you will get a better MPG? That sounds like a performance advantage to me.

Fuels with a high octane rating resist detonation better than lower octance fuels. This allows the engine to run with higher compression ratios, or higher boost.

No offence, but there are quite a few people on here who do know what they are talking about. I come from a job where a 1% change in efficiency for an engine can cost more than an entire car would over the course of a week - it's my business to know how engines work.

 

[RIK]

do higher octane fuels burn slower then? the reason for good mpg..

 

[Type-R]

but on a forum mainly comprised of under 21s

Im 21!

As of yesterday. And i see what both parties are arguing here. I do think that some first hand experience is needed as well as theory, because sometimes its one thing in theory and another in real time.

 

[Andrew]

do higher octane fuels burn slower then? the reason for good mpg..

No. With most fuels, a higher octane rating has negligable effect on the rate of burn, or the amount of energy released. If you use a higher octance fuel with a higher ignition advance, the engine will be more efficient - so you will get a better MPG or higher power.

 

[Low Rider]

Yes, it's a common misconception that higher octane fuels give better economy or higher power output as they stand, however the use of a higher octane fuel in an engine which is designed and setup to use it is a different thing, which is what Mr gfunk failed to explain clearly, (something which I would expect from someone with a PhD no matter who they are addressing).

In sum, I expect that is what he was trying to explain, however he should just look at the term "knock" and realise our point.........afterall this is a "sports" club, where people are performence orientated.

Also 98mpg would not be practical in a gasoline engine, which makes me think if he did infact have a PhD in chemical engineering, he would be working with hydrogen fuel cells and reformers since they have the capabilities of running much higher efficiencies but I'm rambling..................

 

[RIK]

No. With most fuels, a higher octane rating has negligable effect on the rate of burn, or the amount of energy released. If you use a higher octance fuel with a higher ignition advance, the engine will be more efficient - so you will get a better MPG or higher power.

do modern cars advance timing on thier own?

 

[Yom]

Haha. If I put normal unleaded in my pretty much standard micra, it would probably die very quickly. See I'm not a silly ######. I advanced my timing to make use of the high octance fuel.

Results were fantastic. If it had made no difference I would have wound the timing back down and put it back on conventional petrol.

So no offense gfunk, but I think your results are wrong.

 

[masterbiker]

Also there was a very simplistic test on 5 gear where they took 3 cars, normal small hatch, a golf and an impreza, they ran them all on a dyno to find the BHP and toruqe on normal 95ron, then ran it on several different kinds of higher ron petrols, eg supermarket 98, BP Ultamate and Optimax.

I can't remember the figures but the small hatch had no difference with any of the better petrol as it didn't have a engine management system that could take advatage of the higher octaine, the golf had a bit more bhp and a bit more torque but the Impreza I am sure had about much more and a lot more toruque too.

5th gear petrol test here

 

[Andrew]

do modern cars advance timing on thier own?

A lot of modern cars have a knock sensor which can detect when detonation is occuring. They advance the timing until it occurs, then back it off a bit.

 

[Low Rider]

I think this can be closed now.

 

[Dave Bull]

The reason for using higher octane fuels is to allow for more ignition advance, higher boost levels or higher compression ratios, thus preventing detonation in the search for higher outputs.

Trust me, if I run my car on regular 95 octane, I get detonation...on Optimax I don't!

And see your PhD...stick it up your ####ing arse college boy!!!!!!!

####ing racecar wannabes....######!!!!!!!

 

[Andrew]

I think it is just a windup - his language is vague, and doesn't really seem to be making a point. He also doesn't understand or know much about the fuel industry - they do publish papers on fuel all the time, just it's a bit above the level of understanding of most consumers, just look at the SAE for example.

 

[goldstar0011]

Obviously it's better to go into much more (accurately worded) detail at times, but on a forum mainly comprised of under 21s, it's probably not as great an idea, as causing confusion is never a good idea!

LMAO at that comment, I know little about different fuels so I just read the thread but WTF does age have to do with it, I'm 24 and now little about actual engine specifics yet I have a mate who is wounger than me and could run rings around me with engine design and equations.

You'll gain very little respect if you bost that you know better than people on here, start a debate is fine but never dismiss and answer, especially from the master of all (aka Ed)

 

[propus]

Put simply:

Use optimax, super, etc in a car with knock sensors or that has been set up to run on the higher octaine.

Use standard unleaded on cars with no knock sensors of that have been set up to run on 95 octaine.

My BMW 730i V8 has knock sensors, it will run happily on 95 or 98 octaine. There IS a noticable performance difference between the two when pulling hard from stand still.

 

[Andrew]

In which situation do you prefer the Micra over the 730i? I know which I would rather be driving

 

[propus]

In which situation do you prefer the Micra over the 730i? I know which I would rather be driving

To tell you the truth I'm a bit confused.

The 7er is easy the best car I have ever driven or been in. It's big in a good way, VERY confortable, quite with only the V8 rumbling when you floor it, full leather, air con/heating comes on at preset times to cool/heat the car before you get into it in the mornings/after work ect, the OBC says things like "front left fog bulb blown" and "washer fluid low" etc, quick for a heavy car, done over 130mph in it and it was still smooth and pulling but I chickened out, looks sweet, has all the toys under the sun - even the head rests are electric!!

The K10 on the other hand is tiny, kinda ugly, slow (nippy 0-40 lol), only has 4 gears! Wipers are on or off! Rolls like hell going round corners, noisy, has electric nothing (do the head lights work off a dyno? lol). 988cc engine sounds like it should be on a go kart, but all these things put together make it lovable and very very good fun to drive!!!

I really thought there would be no doubt I would hate driving the K10, but I love it. Have sold the 730i while I look for a 728i cos 80quid a go to fill the V8's tank was a joke when it only lasted 250-300miles depending on driving style. I do miss the 7 series, but when I get a new one I WILL keep the micra too.

Hmm, cost of running two cars may be more than the cost of just keeping the 730i in the first place! Just thought about that one as I was typing this.

 

[K10Daz]

I'm not allowed to mention who I work for

We are working on vehicles to be presented around 2012

Why are you not allowed to say? Will you be killed by the mafia? And i hardly think they will read these forums - ur bosses are too busy fornicating with your girlfriend or secretary.

As for your second comment that is also bull#### - I work for Renault and we get periodic updates on new things they are trying out. We also get to know their setbacks, and one of them is the fact that they are struggling to bring emissions down to meet UK standards set by the government, If this is going on TODAY then how can you be working on cars designed for 2012?

Go wear a bib because you are dribbling some amount of pish

 

[def]

Ive read some mags that have dynoed cars with all the different petrol's and all had gains in bhp and det Resistance

And when a 500bhp scooby ran on my mates Klotz race fuel it gave him 559bhp which is quit a gain.

 

[Ed]

I think our point has been made..