noticed a couple of people having a the problem of a flatspot around 2500 rpm like me so thought i have a go at solving it. my first thought after looking into it was auto detonation after hearing a slight tap in the engine so went for higher octance fuel which was v-power + Nos Octane booster (race use not street) which makes it around 105 octane for a more efficient combustion and cant fault the stuff. its an extra £2.50 (335ml bottle) to add to the fuel bill but made such a difference prob gonna buy it in bulk :clap:
round about 2.5k rpm flatspot sorted :)
- Thread starter jamjar15
- Start date
higher octane fuel has no drawbacks apart from cost so no reason it should be bad news 
any ine kniw of any more technical input, for the cause of this notorious flatspot?
any ine kniw of any more technical input, for the cause of this notorious flatspot?
GrumpyTwig
"the troll hunter" with added boost!
Its an octane booster, just happens to be called nos but isnt nos so if all it does is raise the octane of the fuel what damage can it do.....
Iain 007
Platinum Member
It could have a fairly detrimental effect on the engine over time as you are basically forcing later detonation by increasing the fuels resistance to detonation. The car was designed for 95/97 RON fuel and anything higher would require changes to the valve timing. Personally, I'd just deal with the flat spot. The car does have the ability to distinguish between different fuels, It's called a knock sensor in most cars, but I'm not sure whether using 105 RON fuel would be good in the long run.
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GrumpyTwig
"the troll hunter" with added boost!
My understanding of it is that it's no harder to ignite via a spark plug, it just has a greater resistance to predetonation. Maybe wrong.... I am sometimes
resistance to "knock" etc is a good thing.....more ignition advance = more torque (up to a point) helps keep the engine runing to optimum more of the time
My understanding of it is that it's no harder to ignite via a spark plug, it just has a greater resistance to predetonation. Maybe wrong.... I am sometimes
yes this is the same idea i had, just ignities the fuel closer to when its suppost to and not when the fuel wants to detonate, as surely pre det is alot worse especially on revhungry engines as it stopping the momentum of the crank.
im no combustion engine genius but if fuel detonates as piston is on its way up its going to waste energy and put more stress on internals compared to when its at full compression and detonation in sync with pistons
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yes if you've done the gas turbine conversion
Nearly did it. Just couldn't justify going to Stansted to fill my car up twice a week
Nearly did it. Just couldn't justify going to Stansted to fill my car up twice a week
Swing by Cambridge Airport, ill fill it up.
I agree with everyone else, once or twice higher octane ratings are amazing. But cars have a map to cope with certain fuel types. For instance, I run an Evo 9 at many of the countries stage rallies, that is only mapped to 95 RON, purely for the fact that we know that 95 RON is readily available and that if V-Power or anything like that is left lying around for a little while, the RON rating drops. Also when at the pump you are never 100% sure what octane rating you are actually getting due to many factors etc. So if we put any old fuel in it, it kicks up a fuss and we could be facing big engine failure issues.
By increasing the RON rating by around 10 is a huge jump, not sure if it is worth the risk, as I say, once or twice yeh. But what ever you like to do is up to you. Your car.
By increasing the RON rating by around 10 is a huge jump, not sure if it is worth the risk, as I say, once or twice yeh. But what ever you like to do is up to you. Your car.
