I have always known that the 98 octane made the mini run better. The last few times I have filled up they have had none and last time not even the 95. Today i filled up on 98 and my car ran 10 times better. My car vibrates a fair bit on the other one for some reason.

If you added the octane booster to 98 would it run even better?

Long live 98 octane.
DAVID

Only if your engine was tuned to suit 100 octane, Dave
(i.e. compression ratio of > 11.5:1)

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Too many cars, and too little time.

it's really not a simple yes or no answer. The way that your car mixes it is one thing then their's the way your car burns it. this changes in small amounts due to motor and ambient temperature.

Then their's tuning, tuning makes the biggest difference. Valve clearances, timing and air/fuel ratio all need to be set to a Octane.

this is why the older Leaded cars 'ping' on unleaded, because unleaded contains a lower RON (92 instead of 95)

I would say 98 is more than enough, to keep a mini happy. But the biggest gains come from a high octane fuel that is fresh and kept cool (preferably sealed). The octane is the first to evaporate from the fuel so if it's hot and left exposed the octane escapes. also fill up when the fuel is cold (i.e. after a clod night) because you will actually get more fuel due to thermal expansion. fuel is not fuel a high turnover servo will have generally a 'better' high octane fuel than the one that sells very little. I notice on my bike when I pick up bad fuel straight away but it's not always octane that makes a fuel good, impurities and exposure can cause a bad experience too

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-doing a Degree in Mechanical Engineering,
and a few conversions:
13B Extend in a 1600
4EFTE in a mini ute (all slowly)

I added NOS octane booster for one track day, then I found it ran much better on the way home- AFTER I topped tank back up with straight 98 unleaded.
I still have 1/2 a bottle of the crap left...

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

i put shell V power in mine it runs like a dream and even better with the V power sport (100 octane) but if i put the 95 standard unleaded it runs like a bucket of crap..

but at the moment its running abit rich so that might have something to do with it lol

but if u add to much octane to ur fuel that ur engine cant handle it will ping its arse off

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oil leak?..what oil leak..that puddle under the car is just sweat from all that horsepower

So too much octane and it will ping? I must try to remember that.

Am I missing the joke?

I always thought the octane rating of a fuel was a measure of its stability at high compression. Low octane fuels will detonate when compressed too high, where a higher octane fuel will sustain higher compression before igniting.

This explains why highly tuned or turbocharged engines require a higher octane fuel otherwise the engine pings, which is the fuel/air mix detonating when it's compressed, rather than being ignited by the spark. As this spontaneous detonation happens as the piston is rising, it has the potential to damage the piston and/or rods.

Or that's what I thought.. basically that you can't have too high an octane rating, but you only need enough to prevent pinging.. more than that is wasted.

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Simon

The adventures of an owner builder in the Tallarook Ranges

There was a trial of many of these octane boosters in a magazine some years back, most were found not worth the value of the bottle they came in, many actually reduced the octane of the fuel, and power.
I musta picked a bad one...
if you want high octane fuel, buy it, don't tip snake oil in from a bottle....

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Yep, I remember that article. It was in Autospeed (the online Ezine run at the time by Julian Edgar). The values as tested by a scientific engine of some description in a laboratory at the best were between 1.5 to 2 point of octane for 30 dollars spent. About 60 percent of the field didn't even make 1 point, all good brand names too. This was about the time of Autozet (the electronic supercharger! [a PC fan in a tube]), so there must be a whole world of suckers out there.

The finall laboratory verdict was drop into Supercrap and buy some thinners. Mixing more than 20 percent had decreasing values in performance, but the returns were quite high from memory.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

well that answers that then.

I will keep using the v power then and not worry about that snake oil in a bottle

Thanks guys.
P.S where can I get one of those autozet superchargers...they sound awesome

Remember that the V Power Racing (100 Octane) contains ethanol.

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One should never skimp on the zip ties.

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Starlet Conversion:
http://www.ausmini.com/forums/viewtopic.php?t=15484

I only do the 97... I am not hardcore enough to go to 100

Thanks for the heads up

The very best boost in performance that i`ve ever found from fuel was at a race meeting at Echo valley dirt circuit in Toowoomba ,,, there was this guy who had actually crashed his car & was out of the race....& i was out of juice (fuel), (cause they had organised 5 races when normally they only had 3 races),,,so i`d nearly ran out of juice,,, I ran around the pits trying to find some fuel & the guy that crashed had offered me his jerry can full,,,BUT!!! he looked around the pits ,,, all sus like, hoping no one could see him & then shook up the can & said to me to "make sure you shake it up good before you pour it in",,, it was super dooper suspect but he`d obviously used it in his car &&& i was out of juice , so i went with it,,

As it turned out, my car ran like a turbo charged injected rotary on steroids seriously it was an absolute rocket ship!!!!!!!! & i`ve never ever felt a mini accellerate better than that day!!!

BUT!!! my race mini is 13.7:1 compression ratio , full race 1415cc monster so it really liked Av-gas but good clean new mobil av-gas only & super dooper cold plugfs etc etc etc ,,, not a month old shell or whateva,,, IT NEEDED !!!! good clean fresh top quality stuff to run it`s best.

This stuff that thid guy gave me ended up being a mix of one 3rd mobil av-gas,,, with one 3rd toluene,,, & one 3rd methanol

Now,,, i know what a few of you guys (in the know) might say but,,, it was an absolute rocket ship & i lapped evryone (28 cars) twice (except for 2nd place -->methanol injected 265 hemi centura), who i was about to lap at the finish line anyway

sooooo,,, after saying all that,,, octane rating can be improved & can often help,,, but your engine only likes what it NEEDS,,, if you havn`t got a high compression motor, then you simply only need as high an octane rating fuel that suits the NEEDS of your engine ,,, but it does need to be fresh & clean, not old &/or diluted with crap, no matter what the NEEDS are.

if you can all understand all that & how i actually meant it, then cool.

if you don`t understand all that,,, then just run 98 octane from the average servo & don`t worry about anything to do with RON & OCTANE & COMP raios &/or much else

however ,,, if you hear what might sound like "Pinging" or "Pinking" or "Detonation" or have a "Running on" problem (where after you turn the engine off, it keeps running sort of funny after you`ve turned it off), then please do get it looked at by a mini specialist, cause obviously there is something wrong & needs attention to the tune side of things ...&/or maybe you`re compression ratio is too high & could do with a look at



easy-peasy

now please don`t go & mix fuel like i`ve described above cause in normal road cars with low compression (compared to my race engine) you may not actually feel any difference at all,,,&&&&& it`s also highly ILLEGAL for road use.

The race story i talked about at Echo Valley above was over 20 years ago & fuel was pretty dam good back then ,,,But so was my rae engine

ok,,,class dissmissed

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Toluene?!?

Nasty sh!t..

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Simon

The adventures of an owner builder in the Tallarook Ranges