What are Octane boosters. How do they work and where can you buy them?

I keep hereing about the use of these, but is the ECU on the Subaru's not too sophisicated for these things.

I presume that the use of one does not knacker the engine. Would I really be able to see a performance gain on my STI5 which is run on Super.

 

An octane booster is a liquid that is put into the tank with your petrol, it chemically increases the octane of 98 RON petrol to 100-104 depending on the amount added. The ECU in your STi is programmed to run on 100 RON anyway so would not cause a problem. You can get it from Scoobysport, Demon Tweeks or any of the other tuning companies.

 

I put some in my STi on hot days - I don't see any performance increase, but I think powers down on hotter days anyway.
It's quite expensive. I've tried Comma (whole bottle in 1 tank they recommend!) and Silkolene. This is around £8.00 and will probably last 4 tanks.
One definite thing I noticed was that the car was smoother.
I may try an ECU reset with Octane Booster - I'd imagine that would get ultimate results.
Overall, I've spoken to a couple of tuners and the consesus is that it will only do good.
Most accesible place to get it seems to be bike shops.

Cheers

 

Craig,

I use Silkolene Pro boost, but i use a whole can on one fill up. How can you get yours to stretch to four fill ups?
I use it to stop pinking.....And i do notice an improvement on MY93 WRX.
I do use SUL.
And yes you`re correct the Motorcycle trade is the best source for it. I pay £24 for four cans.I only get it at that price if i buy 4 cans, if i only want one can i gotta pay £7.99 each. So why don`t you ask your friendly Motor cycle shop for discount for "baulk" purchase?
I did.....

Cheers
Dave

 

Dave,
I must be a bit thick. I looked at the instructions and thought that the lower %age would be fine. Do you think that 1 tin per tank is worth it? Do you notice anyother improvement.
It's quite a lot extra if I'm doing 2-3 tanks a week.

Craig

 

Assuming you have a 45 Liter tank then a 1% ratio would be .45 Liters which means you must be using less than 1% which isnt going to give you much of an improvement. I also use 1 can per tank on special days ie track days or days where I am going to be doing hard driving in my STI V and I notice an improvement in the responsiveness of the car.

Darren

 

Hmmm
I was never good at maths. That last tin I used was worth it then! I suppose I may as well have peed in the tank.

 

I used silkolene Pro Boost 3 days ago half a bottle - full tank of fuel, does not pink and silky smooth all the way through the rev range, never take it over 6500 revs not yet anyway.

Saj

 

Ok, didn't know about the turbo thing, used him as my "guru" when tuning early Fords cos he only lived about 10 miles away. With that amount then I guess its no problem. I also think the Nissan lambda may be more tolerant to contamination. Worth considering I think. Thanks

Bob

[This message has been edited by Bob Rawle (edited 03-09-1999).]

 

Cheers Bob,

I`ll give the Nissan lambada a try if it fouls up.
I`ll try anything once...

Dave

 

Craig,
Recently I`ve been "Doing" three tanks per week, but i still use a can per fillup.
I used to do a 1% mix but thought i`d try a full can per fillup.(Someone else posted the mixtures a while back, which would take 98ron upto 100)
It Definitely pulled a little stronger.
If i don`t run with the booster, i do notice the difference.
Experiment with the mixtures, but if you mix too much it does have a worse effect than having none.

I`m also considering putting a small mix of two stroke oil in, I remember David Vizard doing some testing and found that a small mix of two stroke oil helped reduce upper cylinder bore wear by ?%.
I used to use it in a Mini & Pinto engine with no problems. Maybe it`s not suitable for a turbo engine.Anyone have any comments on that?

Dave

 

Two points re two stroke oil

It could contaminate the lambda sensor.

It will/could carburise if temperatures are too hot.

Oh, and of course, it will smoke a bit.

Don't think Dave Vizard ever tuned a Turbo, brilliant in his day though.

Bob

[This message has been edited by Bob Rawle (edited 03-09-1999).]

 

But Dave Vizard did put turbos onto Minis & Pinto`s.
The mix required was if i remember correctly 1ml per gallon, or there abouts. I think i used to put 50ml into a tank full(50ltrs).
I never had problems with the plugs fouling, Smokey?
Never noticed, nobody else noticed, only thing they noticed waz the Two stroke smell.
Like a Scoobi aint smokey

Maybe the Lambada will get fouled up, but with such a "Light" mix probably not.

Dave

[This message has been edited by Dave Mitchell (edited 03-09-1999).]

[This message has been edited by Dave Mitchell (edited 03-09-1999).]

 

Just out of interest what do you guys seem to average on mpg?? Even on motorway cruises I seem to get about 17mpg. Is this too low I'm wondering if my car is running a bit rich?

 

Phil T,

To be totally honest I`ve never worked it out. All I do is drive it and fill her up when she needs it
I gauge my fuel by how much I have left for SMILES.
I get any thing from 200ish to 280ish per tank fillup.
The way I drive is when fuel is low I back right off. Otherwise I drive as road/mental conditions dictate.
It`s just the way I`ve always driven.
You get a feel on how far your gonna get from how much fuel is left and your right foot.

Dave Mitchell

 

I get anything from 13, on a track day, to 28, 50 mph on congested but flowing A road to 22-25 "normal" enthusiastic driving. On constant highish speed run, motorway, I get 22-23.

Thats either with Phase 1 or Possum link ecu's.

Bob

 

Interesting stuff, has anyone seen any performance difference with\without octane booster on a rolling road. Seems like quite a cheap mod for track days? I haven't any experience of octane booster on turbo charged engines but the performance gain on pintos was around 5 BHP.

 

Does anyone notice more pronounced engine braking when using booster, or am I going mad?!

 

Just bought some Silko-whatsit and from what I can see on the tin it says about 1.5 percent is optimum.. ie if the tank holds 60 litres that equals about .9 of a litre ie just about the whole tin... Is this correct with super 98 or if you use this can you use the 95 crap ??? Any clues...If this works it will be certainly cheaper than paying for a chip upgrade . 600 notes is a load of Silko... Ps they sold it for 7 pounds a tin... Thais approx 85 tins at 200 miles a tin equals 17K miles... If the motor lasts that long.....

 

SUL only......
I run MY93 with SUL and a can of Pro-boost EVERY fillup.
I`ve never tried UL with the booster. That would probably take it to 98/99ron?
Why bother when with SUL it will go to 100ron.(ish)

Dave

 

Put inthe Silko.. Engine seems smoothere and definately quieter except at about 6K ther is a definate pop in the exhaust... Is that normal... didnt happen before the Silko ..

 

I get no pop from mine but i try not to rev that hard any more...

 

hi there,

Popping ? banging ?

That is caused by unburnt fuel igniting in the "exhaust". You normally get it on over-run.

You get it while accelerating ?

J.



[This message has been edited by firefox (edited 12-09-1999).]

 

Might be just a missfire.. Seemed OK l8R...Will try itt again tomorrow...But also if you dont use high revs,why waste money on the Octane improver ?? I havent heard the engine pink at all but I suppose at high RPM you probably wouldnt hear it ..

 

Clive,
I use the booster because the Scoob was pinking in the mid range, Like 3rd full acceleration...then Pinking.....lack of power...lots of....that sux....
So since I use booster no more problems....Anywhere....


Dave