Octane boosters

Do many people use them - Which is the best to use for the Supra jap engines?

If the car is mapped to run on 99 ron is it safe to use 97 ron and add an octane boost?

Thanks

Ive seen reviews that octane boosters actually reduce power

Recent thread.

http://www.mkivsupra.net/vbb/showthread.php?294569-What-fuel-do-you-use&highlight=Octane

The highest we seem to get in NI is 97 as far as I can find. Would the safest option be to get it remapped to 97?

it depends how aggresive your map is. If the timing is 2 degrees retarded before knock then yes get it mapped! Or get water/meth

97 will be fine, and unless you have an aftermarket ECU there'll be no mapping it otherwise anyway.

If the car is mapped to run on 99 ron is it safe to use 97 ron

Stock ECU? They are not mapped for 99ron and will run fine on 97ron.

Octane boosters foul the plugs which will require extra maintenance and have a shorter life span.

I run my daily driver (jspec twin turbo 2.5l Mitsubishi legnum) on 95. It's fine. It doesn't seem to know the difference between 99 and 95. I'd even say it runs nicer on 95.

Not 100% sure how they chemically work but I did read somewhere on a 'layman's terms' basis that octane booster will increase the effective RON value for 95RON or lower. (By how much is not really defined, but could be up to two points on older fuels).

On 97RON and above fuels the octane booster has nothing much to chemically 'bond' to in order the fuel RON value can be increased. So in effect as some have hinted it can actually have detrimental effects as this un-bonded addition in the fuel goes through the injectors and in to the combustion chamber.

I have heard of some people thinking that by adding 4 bottles instead of 1 believing that they are going to get 8 RON points higher in their fuel....doesn't work like that. If they are already using 99RON fuel they may well be reducing the RON value as they 'dilute' the fuel with un-bonded additives that don't by themselves provide any additional combustive effect over the internal energy of petrol.

To be sure about adding octane boosters to 97RON fuel on an engine mapped for 99RON fuel would probably have to be done on a dyno and computer. (Assuming the map is not able to compensate for differences in petrol fuel types and RON values).

Also, when they state "raises octane by two points", that's actually 0.2 RON. There's not enough in those tiny bottles to do much at all.

You're much better off mixing in 10% Toluene which you can buy from many chemical suppliers. If you tell them you're buying it for use as a fuel additive they'll sting you for tax though.

I would always use the same fuel than it was mapped on.

I stuck two bottles of octane booster in with £60 of 97 super and didn't see any difference except for a few flames out the exhaust , I actually noticed it hesitated a little on full throttle, either that or my coil packs are starting to die

97 runs perfect

95 isn't great but only used for emergency get me home if no super is to be found

Its mapped on 99 with a HKS v pro gold

I will have to try it with some 97 as I cant source anything else but I think I may have to remap to run better with 97 to be safe

Its mapped on 99 with a HKS v pro gold

 

I will have to try it with some 97 as I cant source anything else but I think I may have to remap to run better with 97 to be safe

Talk to your mapper. To be on the safe side, get it mapped on 97 octan.