100 Octane

[Acid]

heyas was just wondering how many peoples have tried using the wynns octane boost that takes 96 up to 100 and works out costing less than 98.
any replies would be great cause am thinking of using it.

[Fishy]

Don't waste your money mate you won't notice any difference.

[Fishy]

I could run mine on diesel and it won't make any difference, piece of crap Honda's!.

[MSTRS]

Plenty of threads about octane etc. Consensus seems to be "No difference unless you make changes to the state of tune".

[Grahameeboy]

I could run mine on diesel and it won't make any difference, piece of crap Honda's!.

But at least it would make a noise??

[enigma51]

I could run mine on diesel and it won't make any difference, piece of crap Honda's!.

Told you to buy a suzuki. O no it was not you it was boomer I must have been tired of explaining to him why honda's are crap

[enigma51]

But at least it would make a noise??

so does a hoover

[bugjuice]

yeah, wouldn't really be worth it.

91 is cut with more additives than 95/98. Once they're in the bike, you can't take them out, so adding 'octane' isn't going to cure the fact that you could have crap fuel in there. You could use 108 octane (AvGas) and add the octane boost to it, and it'll probably run really really crap..

Unless the engine has been modified to run high octane stuff, the additive stuff doesn't really do anything, the pump stuff works just fine. I can't even tell between most of it, I don't know what all the hype is

[SimJen]

You either need high compression or very advanced ignition timing to make any use of high octane fuels.
In some cases high octane actually hinders performance if the motor is not tuned for it.
High octane = lower flammability (ie burns slower).

[Acid]

thanks for answers and nice choice of bike slimjen thatll be what i want later on

[FROSTY]

buggie sorry mate its the 95 thats got the most additives.

[nadroj]

Best mix is 60% 91 octane & 40% 95/98 octane according to a local dyno operator tuning race engines limited to pump gas. Have tried av gas and octane booster in the past but unless you require the higher octane due to compression ratio then you're wasting your time.

[bugjuice]

buggie sorry mate its the 95 thats got the most additives.
k, ma bad. I thought the fuel came pure and they cut it back with additives, which lowered the octane rating

i'll shut up then! :shutup:

[Mental Trousers]

Some bikes do prefer a high octane rating. I've noticed on mine that it has a slight pause when snapping the throttle open on 95 but doesn't do it on 98. Seem to get better milage on 98 too.

[Lou Girardin]

I tried a tank of 96 in Gisborne as it was so hot I got a trace of pinking. Bike ran noticeably worse than on 91.

[avrflr]

I have a little inside knowledge (I work for BP, not pumping gas). I agree that you won't get any benefit on a stock 250 from higher octane fuel. Some people wouldn't even notice the difference between 91 and 95. If you raised the compression of your motor it might make more power, but you then might run into problems with detonation, so then you would need higher octane fuel. I would say at least 90% of people think that if you put avgas in a street car/bike it will instantly turn into a rocketship. And don't get me started on confusing avgas with jetfuel. Very frustrating for a fuel nerd.:angry2: If you are having problems on pump fuel with a stock bike, a tune might help.

[Motu]

Octane boosters work,if you need them - but not Wynns,I've used that crap and it did nothing.You need 104,or 108 octane booster - get them from Pioneer or Segiden Truck and Auto.But my old Falcon needed it,the old 2 valve high compression motor rattled like diesel - why do you need an octane booster???

[Sutage]

i disagree
98 feels smoother and runs a hell of a lot better and has quicker acceleration i find
plus its like 12c more in my 11litre tank its like.. 1 dollar, the small notice is worth 1 dollar to me
91 can leave a build up of shit in ur tank too

[SPman]

Some bikes do prefer a high octane rating. I've noticed on mine that it has a slight pause when snapping the throttle open on 95 but doesn't do it on 98. Seem to get better milage on 98 too.
I noticed it liked 98...91 was OK ...hated 95

[avrflr]

i disagree
98 feels smoother and runs a hell of a lot better and has quicker acceleration i find
plus its like 12c more in my 11litre tank its like.. 1 dollar, the small notice is worth 1 dollar to me
91 can leave a build up of shit in ur tank too

Hmm, interesting. 98 doesn't have much additive in it because it's refined specifically to be a 98 octane fuel. I've heard that engines running on premium tend to have less carbon build up in them, but I've never heard of 91 leaving "shit in ur tank". Shit can end up in the fuel at the gas station for all sorts of reasons....

[sAsLEX]

Very frustrating for a fuel nerd.:angry2:


ok maybe you can explain. 98/95/91 and all this is just a octane right!? all using the same basic fuel with shit added in to raise the octane rating without increasing the amount of octance in there, so getting to my question: is 98/Ultimate/other generic high perfomance petrol any better than the rest of the shit the big 4 bring in to this country!?

[avrflr]

ok maybe you can explain. 98/95/91 and all this is just a octane right!? all using the same basic fuel with shit added in to raise the octane rating without increasing the amount of octance in there, so getting to my question: is 98/Ultimate/other generic high perfomance petrol any better than the rest of the shit the big 4 bring in to this country!?

The fuel at most gas stations (91 and now 95) gets refined at marsden point. Various additives are injected just before it gets loaded into the tanker. The additives have various purposes like detergents to dissolve the shit in your fuel system and octane enhancers. The mobil premium fuel for example has an octane of 97.3 or something.

98 is different, it is refined in western australia and shipped to tauranga. It still has additives injected before it goes in the tanker, though.

[sAsLEX]

thought it must be, used to be best to get challange gas as that was shipped from overseas rather than marsden, we are finally getting slightly better deisel *sp* in some places is this shipped or refined here? I ask this as I read a comparisn of the black pump fuel a while back and we were on par with Nigeria for Sulphur levels etc

[Toast]

I noticed it liked 98...91 was OK ...hated 95

I think a lot of people find this. I do. Carb'd bikes especially seem to hate the extra additives in 95/96.

I always use 98 when it's available (BP only, Mobil stuff is just 96 with even more shit in it). My 'Blade seems to run a couple of degrees cooler in equivalent riding conditions, compared to 91, too.

[avrflr]

Sorry to go OT but yeah, our diesel is refined here and the reason we have high sulphur levels is money. Marsden pt wasn't originally set up with low sulphur diesel in mind so will require major investment to fix, which is why they will drag their feet all the way.

[FlyingDutchMan]

Sorry to go OT but yeah, our diesel is refined here and the reason we have high sulphur levels is money. Marsden pt wasn't originally set up with low sulphur diesel in mind so will require major investment to fix, which is why they will drag their feet all the way.

They've completed the upgrade of Marsden point about a month ago - all diesel here is now low sulphur. Read this:

http://www.consumer.org.nz/newsitem.asp?category=News&docid=2358&topic=Cleaner%20petrol%20and%20diesel%20on%20the%2 0way
Its also the reason for 95 octane at the pump now instead of 96.

[Hitcher]

So what's being postulated is a premise that there is a bunch of additives that can be added to your fuel at the bowser that improve the performance of that fuel in your engine, over and above all of the stuff that the oil companies already add?

With the exception of the tetra-ethyl lead substitute that comes in the orange syringes for use with older cars, I would say "What a load of crap!"

At best Wynns (and other proprietary) additives are harmless. Caveat emptor.

[Motu]

As the adds say - they contain ''JET'' fuel.....true,they are mainly kerosine.But I know for sure that 104 and 108 octane boosters work,my Falcon engine was built before non lead fuel,and the only way to stop it rattling was 100 octane or 104 and 108 boosters,I tried the ''service station'' boosters like Wynns and STP,but they never worked.When the BP ultimate came out I ran it on that exclusively,and it ran fine.It's only old school cast iron head 2 valve combustion chambers running 60s high compression that need high octane,most standard engines built after the late 70s will run on anything.

[scumdog]

Put 98 in my 'lorry', it certainly pinked a whole lot less than with 96, ran a little better around town too.

Went TOO well outside Dangerous Drop-in Dwelling but that's another story...

[Fooman]

...CNG!

CNG has an octane rating of 120ish! If it's high octane, it must be good! :brick: Actually the only problem with CNG (other than tank range), is that the engine also had to run using petrol, which meant that the engine was optimised for neither!

There are a number of issues with petrol/octane/leaded/unleaded/additives:

As mentioned, old, high compression cast iron head motors need high-octane. They may also need lead, as lead compounds lubricate the valve seats. Lead compounds also increase octane rating. If they have hardend valve seats or inserts, they only need high octane, not lead, to stop pre-ignition. Old, low compression motors might have had to run leaded (e.g. old super) fuel, or lead additives, for lubrication, rather than for any performance reasons.

Modern, new, alloy head high compression motors can get away with unleaded, low octane fuels, because the aluminium heads transfer more heat away from the combustion chamber (if designed properly), reducing hot-spots that can initiate pre-ignition. The late 80's Corvette ZR1 motor could run 89 octane with a compression ratio of 11.25:1 because of this.

As mentioned, sticking in a octane booster or using higher, will not necessarily get you more power, unless you advance the ignition and/or increase the compression. Some cars have pre-ignition sensors, and will change the ignition timing on the fly to get the most out of the fuel in the tank (i.e. retard the timing until no pinging is present). It's pretty hard to increase mechanical compression on the fly, however pressurising the intake (e.g. turbocharging) effectively increases the compression (pressure ratio) inside the cylinder.

There may be slight differences in the calorific value (how much energy per kg)in fuels - that is what the dyno tuner would be seeing with his combination of 91 and 96 - more energy = more power, which is why there were some really exotic fuels in Formula 1 with normal octane ratings.

Additives shouldn't really affect the performance, as they tend to be similar across all fuels - a dye (petrol is colourless without), detergent for cleaning, antioxidants and metal deactivators to prevent the fuel degrading, corrosion inhibators to prevent tanks rusting etc. Fuel recipies may change depending on the season (e.g. to get enough vapour on a cold start), but I don't think NZ petrol does.

Any difference seen in operation is probably due to a cleaner batch of fuel, or the combustion may simply be better with a different type of fuel.

Check out Bruce Hamilton's gasoline faq: http://www.faqs.org/faqs/autos/gasoline-faq/part1/

Cheers,
FM

[k14]

Went TOO well outside Dangerous Drop-in Dwelling but that's another story...
Yeah theres quite alot of hooliganism that goes on outside that house. Heard that there was some sustained loss of traction the other day too. Pity you weren't there or you could have given em a ticket :laugh:

[sAsLEX]

It's pretty hard to increase mechanical compression on the fly,

it has been done, the whole top half of the motor would rotate to shorten the combustion chamber to increase compression and then the the other way to lengthen when used with a turbo, was rather ingenious


linky:http://www.popularmechanics.com/automotive/auto_technology/1266656.html

[Acid]

i heard 96 from gull is imported from overseas

[Toast]

i heard 96 from gull is imported from overseas

Yep, pretty sure it is. I reckon my bikes like that stuff even more than the BP 98 too.

[quickbuck]

You could use 108 octane (AvGas)

Since when????

There is 100 octane avgas (Green)
100 octane low lead avgas (Blue)
115 Performance rating avegas (Can't remember the colour as it was 15 years ago when I did my mechanics course)
140 Performance rating avgas (purple)

Most avgas used in NZ is the good old green river.

Note: You can't get an octane rating above 100, that is why it is called "performance rating".

To put an extra 2 cents in, my CBR goes best on 98 (or 8000 if I stop at Mobil).
It isn't wise to just fill your bike with avgas either, as the amount of lead in it is enormas, and the deposits will fowl your little plugs in no time. The aircraft I use to maintain used to get their plugs serviced every 30 hours (yes, not long), and they were well caked in that time.

[KLOWN]

octane booster is not good for your bike/car I had to run minimum 98 on my skyline and was running octane booster on top of the 98. When I had it dyno'd the guy told me to not use occtane booster it damages the spark plug and contaminates(sp) the fuel system with shit. If you want higher octane fuel you can buy it from pioneer(sp) I ran a fuel called ms103 its 103 octane and is $5 a litre or cr12/cs12 (can't remember the name) which has even higher octane and is $20 a litre. Av gas is no good for cars or bikes because it is designed to run at 2000-3000rpm or 3000-4000rpm, I can't remember.

[KLOWN]

i heard 96 from gull is imported from overseas
isn't all our petrol imported?

[Bonez]

Since when????
Hey isn't AVTUR the best? The AV means it flys and TUR stands for TURBO after all doesn't it? :devil2:

[quickbuck]

Hey isn't AVTUR the best? The AV means it flys and TUR stands for TURBO after all doesn't it? :devil2:
Yeah, that's it bonez ;)

[Hitcher]

isn't all our petrol imported?
No. Thanks to the "gold-plated" refinery at Marsden Point.

[scumdog]

Yeah theres quite alot of hooliganism that goes on outside that house. Heard that there was some sustained loss of traction the other day too. Pity you weren't there or you could have given em a ticket :laugh:

Yeah, just lucky for them I wasn't there eh?:eek:

Where's a policeman when you need one???

[bobsmith]

ok, just my 2 cents worth.

Octane rating is NOT a measure of how much "octane" is in the fuel.

Rather it is what is called an "anti knock rating" It is a measure of how resistant the fuel is to a "knock" which refers to explosive combusion of fuel inside the cylinder. (you want the fuel to burn nice, evenly and gradually) By having a higher octane rating you are able to run your engine at higher rpm and temperatures without getting "knocks"

So seeing that fuel with rating of 91 is more volatile than 98. If your engine is properly tuned to 91, it will run much better and efficiently. You can use fuel of higher rating without doing damage but you should avoid using fuel of less octane rating that the one the engine is tuned for.

Octane rating is based on what the engineers back in the days when additives were not available and fuel quality wasn't as high decided the maximum anti-knock properties would be for fuel and is based on that. So theoritically a fuel with octane rating of 100 would have the best anti knock properties possible.

Since fuel tech has advanced, now you are able to get fuel with octane rating of greater than 100. For example, avgas used in New Zealand has octane rating of 110 which means its anti-knock properties are 10% greater than what they thought a while ago was the maximum obtainable. In some other parts of the world they use octane rating of 120 for avgas.

I can't remember what the hell I'm supposed to be talking about but hope this helps.

(edit) - anyway the point I was trying to make is that higher octane rating does not equal more power without retuning the engine for the fuel. and if you use lower octane rating you increase the chance of knocks which can damage your engine. And so in hotter temperatures use higher octane rating.

[boomer]

But at least it would make a noise??


oooooooohhhh :eyepoke:

i'll store that one for later :buggerd:

[Fooman]

Octane rating is based on what the engineers back in the days when additives were not available and fuel quality wasn't as high decided the maximum anti-knock properties would be for fuel and is based on that. So theoritically a fuel with octane rating of 100 would have the best anti knock properties possible.


Actually the octane rating was set by a direct comparison between 2 hydrocarbons. Heptane, (C7H16) and 2,2,4-Trimethylpentane, also known as ...(drum roll please)...iso-octane! 2,2,4-Trimethylpentane is an isomer of octane - both have the same chemical formula, C8H18, (well technically iso-octane is (CH3)3CCH2CH(CH3)2 ) but different structure.

Heptane was set at an octane rating of 0, iso-octane was set at an octane rating of 100, and any fuel was compared to those and mixtures thereof, to assign an octane rating. Fuels with higher octane ratings (e.g. ethanol at 108ish) have been around since the octane rating was developed, 100 wasn't set as the maximum that could be reached at the time.

Hopefully, the following will all line up (plese be a fixed width font!) (dots are for alignment only - forum doesn't like leading or double spaces)

Heptane =

..H H H H H H H
..| | | | | | |
H-C-C-C-C-C-C-C-H
..| | | | | | |
..H H H H H H H

Octane=


..H H H H H H H H
..| | | | | | | |
H-C-C-C-C-C-C-C-C-H
..| | | | | | | |
..H H H H H H H H

iso-Octane =

......H........H
......|........|
..H H-C-H..H H-C-H H
..|...|....|...|...|
H-C - C -- C-- C - C-H
..|...|....|...|...|
..H H-C-H..H...H...H
......|
......H

Cheers,
FM

[guzziguy]

I don't trust 95 octane any more. Used it a couple of times and bike performed like it was running out of gas all the time. Switched back to 91 and threw in some injector cleaner and she's sweet again. Oil companies put 'slops' back into 96 octane (I worked for one for 20 years)- it's a mix of everything they store resulting from ship discharges. They can't put it into 91 coz it's easy to put it out of spec. It is monitored/tested and should be fine but you never know do you? As for 98, if they had it in Nelson I'd run the bike on it all the time. The spec is very high, performance is better, it's cleaner and more economical (probably because you reach cruising speed with less effort).