MunkeyBoy

The performance benefit of using Optimax is similar to that of cleaning your car IMHO i.e. physcological. The S always feel more "together" after a damn good wash and polish, much the same as the "feeling" that the S seems to respond better as you pull away from the Shell forecourt.

I use Opti mainly because A: it's one of the highest octanes avalible (BP stuff is 97 and often more expensive) B: a shell garage is the closest to home and C: because it seems to have a higher mix of detergents.

Oh and i get double shell points equating to around

Finesse

AquilaEagle
In a vllage in West Essex

GTFCTIM
[QUOTE]
Surely a 20 mile drive to get some optimax is a good excuse for a 'pointless' drive!

mariawhite

I use 95 cos I have a petrol card and get my wrists slapped very hard if I try to use 98.. I have had no problems, but the car does behave very dfferently on those occasions where the garage is out of stock of 95 and I have to put 98 in!

GSi

Never really noticed the few times I put 95 in mine, certainly wasn't as bad as some guys on here seen to have experienced

Edlover

U lucky u can even get 95 octane. I live in Jhb (Johannesburg) and they only have 93 petrol here! When i drive to the coast (Cape Town or Durban) I use the 97 thats available. Combined with the high altitude in Jhb, the net effect of poor petrol and air is a 17% decrease in power.

There are no mods to the SA S2000's coz of the petrol so there shoudnt be engine damage. The Subarus that usually make 208KW (280BHP) have to be detuned slightly to run on the sh!t for fuel we have here.

LOADESMOORE

I tried 95 for the first few weeks of ownership and when I changed to 97 then 98 I found that just the 97 produced the most amazing improvement in smoothness, pick up and power. I cannot detect any difference between 97 and Optimax. However, when I tried 95 again for a long motorway run and we had to stop/start in a queue the engine started cutting out! No trouble since we went back to Sainsbury's 97.

I also noticed that EVO or some similat mag has a long termer and the driver reported exactly the above symptoms running on 95.

David

ade73

Read this thread, think brian and myself explain it pretty much.

https://www.s2ki.com/forums/index.php?showt...56935&hl=octane

JamieS2K

Where in Essex , I live there ? I always use optimax or BP ultimate , couldnt risk losing that few bhp

jmd2000

I'm on my second tank of optimax, and still think it produces less mpg, than Sainsbury's 97, but is better in stop/start traffic. I haven't decided yet what my long term choice will be. (Although Sainsbury's is closer to home and less of a fag to get in and out of that the Shell station at the bottom of the M32, closer to work)

eyeofthetiger

I was going to start a thread on this topic myself but decided against it as I thought I would get "read the technical FAQ thread" X100 comments(I have by the way

Last week when I went to my shell garage my intention was to fill up with optimax, I got to the pump 87.9p vs 78.9p premium unleaded. To me 4-5p is nothing but 9p is quite a difference and I eventually decided to fill with unleaded.

My question is to owners who have used both fuels in a short period of time...Is there a NOTICEABLE difference in smoothness/performance or do you feel the differences described are a placebo effect?