SimonBriggs

I've had my 96 reg wrx JAP import impreza for two weeks and have been using Optimax petrol only. The car has been running fine. I know the Japs use 100/102 ron but I haven't had any issues running on Optimax. Can some please clarify whats what?

1. Do I need/have to use an octane booster?
2. Can I just use Optimax on its own?
3. Which booster would I need and where do I get it?
4. Are octane boosters expensive? I was in Halfords (I know bad idea)the other day and they sell octane booster for £6 a bottle, it says to use the whole bottle each time you fill the tank! does this mean I'm going to have to pay an extra £6 a week??

Thanks in advance

greasemonkey

1) Have - no. Need - yes, to be safe. You should really get yourself a KnockLink as this will give you a visual warning of det. If you don't have one though, it's much better to assume that it is and put booster in than assume you're safe, only to be faced with a blown engine a few months down the line.

2) See above.

3) Not the best person to ask as I got my car remapped, eliminating the need for booster. However, I think you'll find NF and Millers are fairly well thought of here. Try Scoobysport, Scoobyworld, your local motorsport stockist or the other usual suspects.

4) Are octane boosters expensive? They're cheaper than a new engine! If you're planning on having this car for a while though, getting it remapped ASAP may prove to be a more cost-effective option.

You do have to use a measured amount of booster every time you fill up, although you won't use a whole bottle of the proper stuff on one tank. Depending on the way you drive your car, it may end up costing a few quid more each week, but as mentioned, that's cheaper than a blown engine.

MickeyWRX

how much would it be to get the car remapped and where in the north east could you do this - or near enough?

cheers!

SimonBriggs

Are Jap import cars fitted with catalyst converters?

Jo Peters

Hi, just my two pennies worth ..... I've run my MY95WRX on SUL and then Optimax for the last 3 1/2 years. Never used octane booster. Don't have a knocklink. So far, I've had no problems. Had it rolling road tested last year and they checked for detonation and it all appears to be ok.

My partner has had his STIiv for the last 4 years and run it on the same as me. He has only used octane booster on the 12 trackdays he's done but not normal road use. No knocklink and so far, no problems with detonation either.

Jo

DutchClutch

Simon,


I have a simmilar WRX engine(orig.260BHP aprox.) from Japan,which came in place of the original blown-up GTTurbo-one(MY99)
We here have RON98 on every street luckely.

I had the engine remapped with the ECUTek-method,and all worked out very well.It now has now a poweroutput of 280BHP.Mind you,the engine is equiped with all my original MY99 parts(except the injectors)and therefore connected to the MY99 ECU.

To bring your fuel to a higher octane-level,there is a much cheaper method,by the way.You just add some 'Tolueen'(=Dutch) to your fuel,which can be bought in every paintersshop.Wich amount I can not tell you,but it is a very effective and safe method I understood from some insiders.
Maybe someone here know's the details?

Anyway,have fun with your new car!

Grtz.Arend
Holland


[Edited by DutchClutch - 04/08/2003 17:07:23]

M0NEY

Same as Jo - dont bother with octane booster - just use optimax.

Ive heard of people running unleaded for years with no remap.

WOuld definitely stick to atleast SUL or Optimax though

SimonBriggs

Thanks very much for the advice, glad to see other people are just using Optimax for jap imports as well. Was starting to get worried.

highlander

I have also run on only Optimax - hasn't been a problem - however I would suggest if you push the boost up a bit higher (and its very tempting) use the octane booster.
In fact on any of the imports if you further modify them use octane booster.

Remember a simple mod like fitting an induction kit equates to more air getting into the mixture - therefore leaner mixture on lower than expected octane rating - can lead to detonation and melted pistons etc.....

If in doubt consult one of the many specialists out there. A new engine is an expensive business!!!!