anthscooby01

My 53 model STI has 'use only 98 ron' sticker on fuel filler. It has always been run on Optimax but obviously like rest of UK our local Shell has none and not expecting any for couple of weeks at least. Have been using Ultimate but car does not like it at all and as it is 97 ron I am not confident that engine will be ok as a few seem to be going pop lately. Is it safe or should I stick some octanr booster in.

Anger

iTrader: (4)

I would stick octane booster in if your car feels like it doent like it, better to have it running right especially if your going to have to wait a couple of weeks for optimax

TonyBurns

iTrader: (3)

The PPP is mapped for 97 ron fuel so you will be ok, it should also run fine on 95 ron but with reduced performance, octane booster isnt needed on a uk car unless seriously modded.

Tony

Wannabe

aye me too mate, i dont like it either and its so much more than Optimax.

cant find any anywhere.

What about TSL 333 is that to modded for 97 ron?

Sy

Dave_68

My 05 STi PPP dosen't like it

B0DSKI

iTrader: (17)

Put Tesco 99 Ron in my 03 STi PPP Yesterday and it's running just fine

Gutmann pug

It will be fine on any of the super unleaded grade fuels. If you are worried just dont drive it at 10/10's till you can get optimax again.

Dont get caught up in the ''it will blow up if I dont use optimax or octane booster'' crap.

Gary

stilover

On my second tank of Ultimate now (have 05 STi PPP) and i have to say that the first tank it didn't seem to like it, but mid way through my second tank now and on New Year Eve while coming back from my mate house it was pulling like a train in the mid range. Deffo felt better than on Optimax, although it doesn't seem as keen to rev to the red line as much as it does on Optimax. The ECU must have reset itself now for Ultimate and before it wasn't giving clean power delivery while now it does. It's hard to tell which is best for torque below 3-3500rpm. If I had to bet, I'd say Optimax was better. Ultimate better between 3-3500 to 5-500rpm, then Optimax above that.
Although it could all just be in my head.

Will go back to Optimax though when it becomes available again.

Scooby-Monster

Tried a few tanks of Ultimate on my 05 Sti PPP, doesn't like it at all, am using Tesco 99Ron and all seems good whilst it's fave tipple of Optimax is not available. I wouldn't say that Ultimate would cause any probs, just doesn't run as well... so to fully enjoy the car I personally don't use it.

Dan

anthscooby01

Just managed to get tank of Optimax again. Its available at Gilesgate, Durham. as far as I can tell they are only Shell garage locally to have had delivery. Prob take a few days for car to get used to it again though just been for blat along fave road and its pulling better already.

D1CCY

Tony,

How confident are you about a PPP car being "safe" on 95 RON. My gut feel is that you are right but it would be nice if Prodrive confirmed this. Just like to know in case of dire emergency.

My experience on Ultimate (03STi PPP) is the car feels crisper but a bit rougher. Switching back to Opti is a relief as it runs much smoother. Can't really see why the difference should be so noticeable, I wonder if Ultimate has additives that make flame travel faster.

Cheers, Diccy.

What if ?

I have been running Tesco 99 for about 4 weeks now and have to say it works brill in my MY05 STI PPP. I ran Optimax from day one till then. I put in BP Ultimate last weekend and it doesn't pull as well low down (for sure). I can't wait to run it dry now to fill back up with Tesco 99. I will cycle once every 4 tanks with Optimax though just to take advantage of the cleaning properties