Shell 'Optimax'

Posted by: J.N. on 13 October 2002

Is it worth it?

Anyone tried it?
Posted on: 13 October 2002 by Mike Sae
You mean the gas?
Posted on: 13 October 2002 by Bruce Woodhouse
I tried it a while back, consistently filling my car over a month or so which included a long holiday driving around Scotland (where it happened to be available at the petrol station close to our accomodation).

I'd definitely say it felt different, overtaking had a bit more bite and it all felt a fraction more zippy. The car is a 2.0 Alfa 147.

EVO magazine recently ran some lab tests on the stuff, including endoscoping engines after use and looking at the deposits around valves etc. The results were impressive-engines looked cleaner after usage and the performance figures were up on 3 out of 4 of the cars they used it with from memory.

The snag is finding the stuff, I should make the effort more and I guess to really make a difference you need to use it exclusively. I am just building a Caterham Seven and intend to make the effort to run this on it all the time.

Bruce
Posted on: 13 October 2002 by Tony Lockhart
We use nothing else in both cars. Subjectively they are smoother and rev more freely.
Evo magazine did a test in their June 2002 issue on three cars. One of the tests was a boroscope check of inlet valves. These were definitely cleaned by the Optimax.
They also carried out in-gear acceleration tests, and all three cars were faster, the Civic Type R being around 1 second faster in most 20mph increments, in 5th gear.
The other 2 cars, a BMW and a Jag, were also faster but not to such a degree.
Evo said Optimax was almost worth the extra cost for the cleaning properties alone, any performance benefits being a bonus.
It takes 2-3 tankfuls to feel the advantage, this might be due to the valve cleaning. I think the fuel is ultra-low sulphur, so it's better all round for engine/exhaust/environment.
The FIA's own lab tested the fuel, and I think it came out at about 99 ron.
Use it, and if you don't like it go back to 'normal' unleaded!
Tony
Posted on: 14 October 2002 by Bosh
Interesting, so is Optimax equivalent in RON-terms to Super-unleded then? If so this will account for a definite difference in performance.

I seem to recollect comments in Autocar to the effect that the BMW 330i (230bhp) and the Clio 172(172bhp) came no where near these power figures with normal unleaded (95 RON), requiring Super unleaded (98 RON) to do so
Posted on: 14 October 2002 by John Channing
quote:
with normal unleaded (95 RON), requiring Super unleaded (98 RON)


Most super unleaded is 97 RON, Optimax is 98. With turbo cars like mine (Audi TT) it takes a couple of tanks of fuel for the electronic engine management system to optimise itself for the higher RON fuel. My TT feels very flat with 95 RON and is noticeable quicker, but also noisier, with Optimax.
John
Posted on: 14 October 2002 by Dave J
My IT Manager had recommended trying it, referring me to the EVO assessment, which I hadn't read. I confess that, up until that point, I had thought it was just a branding exercise and doubted the claims.

I noticed a difference by the second tankful and was very impressed with the improvements in performance (in-gear acceleration is notably quicker), response, reduced mpg and general smoothness. Since then I've sought it out pretty religiously.

As a bonus, it tends to be a few pence cheaper than 'normal' super-unleaded.

Dave
Posted on: 14 October 2002 by NeilM
I have been running in my 1986 Porsche 911. Definitely a big difference and worth the money for the extra fun I am now having. I wasn't aware of the cleaning properties so this is an added benefit to me.
Posted on: 14 October 2002 by JohanR
As Shell is sponsoring Ferrari in F1 I'm using my constitutional rights not to buy anything from that company!
And I'm not smoking Marlboro (I don't smoka at all, but that's unimportant) or using a computer with an AMD prosessor in it.
One of my cars have Bridgestone tires, but nobody is perfect...

JohanR
Posted on: 14 October 2002 by Tony Lockhart
Okay, I've found the lab test on the fuel. It's in the Miller Oils advert in the programme for the Ferrari Festival at Brands Hatch this year.
The tests were carried out by ITS(the FIA fuel testing laboratory) on behalf of Millers Oils for RON and MON ratings.
Optimax came out at 98.3 RON and 86.9MON, while Shell's own premium unleaded measured 96.1 and 85.0 respectively.
Tony
Posted on: 14 October 2002 by Dev B
Is little/no different to any other super unleaded.

Dev -- who knows a bit about this sort of thing
Posted on: 14 October 2002 by Tim Oldridge
Optimax does make a performance difference - I think simply because it's a higher RON than the other garages' super unleaded (at least 98.5 as opposed to 97). The additives included in Optimax I suspect do not affect performance in the short-term.

Clearly there will be differences between different engines. For example, although most newish cars have quite sophisticated engine management systems, not all will be programmed to advance/retard the ignition depending on the octane rating of the stuff pumped in. As a rule of thumb, any engine with electonic ignition for which super unleaded is recommended will be programmed to cope with a different octane. Obviously this will enable the engine to adjust for 95, but usually this will also mean adjusting for better than 97 - many continental European countries offer super unleaded at 99 RON.

I suspect there is also greater scope for adjustment of the settings with turbocharged engines, by their very nature - hence TT and Impreza drivers seem to be very keen on the stuff.

If doing a comparison, I suggest you allow for a complete tank of Optimax before expecting to feel a difference. On my Audi, it takes this long for the engine management system to adjust its settings.

I more or less religiously stick to Optimax. Occasionally I accuse myself of falling for the marketing hype, but a tank of 97 RON quickly cures me of that delusion.

FWIW

Tim

Dev - it's about time BP got into the act.
Posted on: 14 October 2002 by Simon Matthews
I didn't notice much or any performance gains over 97 ron fuel after putting in a full tank of the stuff, however the car did stall once or twice when using it. Do people think this is connected to the fuel change? - If this is the case then is not better to stick to 97? ( the grade the engine set up has been optimised to I assume ).

(944 S2,3 litre/4 cylinder/ fuel injected)
Posted on: 14 October 2002 by Hammerhead
Hi Simon,

If you open your fuel flap, it should say which RON figure your '44 is optimised for. My 2.7 says min of 95 and confirms this in the handbook. Have you had a look at either?

Anyway, friend was over in his 964 C2 at the weekend... You don't need better fuel, you need 3.6 liters of flat six behind you! :-)

Steve
(944 2.7/4 banger/fuel injected)
Posted on: 14 October 2002 by Simon Matthews
Stevie

Yes, same RON story with mine, maybe the couple of stalls were coincidental. Doubt I will lose sleep over it anyhow!

Poke is plenty ta very much.
Posted on: 14 October 2002 by Mark Dunn
Hi Alan:

Some questions and general comments:

1. Does Shell plan a similar fuel for the U.S.?

2. I assume that RON is the octane. Is this correct?

3. Do you know if the method of determining octane in the U.K./Europe is the same as in the U.S.? Over here they call it the 'R+M/2' method.

Octane here is generally offered as 87, 89 and 93. In some areas you'll get 85 and 91 too.

It's interesting to note that in the U.S. the octane is usually changed by the addition of something called MTBE (from memory). This stuff prevents pre-ignition by slowing the burn but also is not itself particularly volatile, so effectively (and all else being equal) you'll get *less* mpg with higher octane fuel because there's less actual fuel per gallon.

Obviously there's many other factors that affect economy and performance as well.

Anecdotaly, I have a Honda Valkyrie motorcycle (flat six engine Mr. Dempster!) and as stock it runs on 87. One of the least expensive and most effective mods is to replace the reluctor, or 'trigger wheel' with one that advances the ignition 6 degrees. As well as putting a SEG on your face from 2500 to the redline at 6500, it also increase mileage by 2-4 mpg (4 in my case). You *must* run at least 89 and preferably higher when this mod is fitted. The new reluctor is $24.95 and takes 30 minutes to fit. 93 octane fuel at my local pump is $1.50/U.S. gal. It's a no brainer :-)

Best Regards,
Mark Dunnn
Posted on: 14 October 2002 by Tony Lockhart
Mark,
Yes, the formula to work out the US equivalent octane rating is Ron + Mon/2. So, at this time of the morning, I think that Optimax would be roughly 92.6 in the US.
Tony
Posted on: 15 October 2002 by Matthew T
quote:
Originally posted by John Channing:
quote:
with normal unleaded (95 RON), requiring Super unleaded (98 RON)


Most super unleaded is 97 RON, Optimax is 98. With turbo cars like mine (Audi TT) it takes a couple of tanks of fuel for the electronic engine management system to optimise itself for the higher RON fuel. My TT feels very flat with 95 RON and is noticeable quicker, but also noisier, with Optimax.
John


Most super unleaded is well above 97 RON. The West European countries all (I think) have seperate specification on RON and MON which are 10 points apart in the specfication. However, the majority of blending components have a larger spread then that and therefore the MON spec is harder to reach so nearly every refiner is giving away 1 to 2 points of RON. The US specs are based on the average of RON and MON.

Gasoline could be a lot cleaner, some of the stuff that goes in is pretty unpleasent. Much will be changing in 2005 with changes in EU gasoline legislation (less aromatics and much less sulphur).

MTBE (methyl tertiary butyl ether) is probably one of the best blending components out there regarding emissions and improved performance, high octane and relatively low RVP. Any Europeans in the know are having a good laugh at the U.S. right now whilst any Americans in the know are despairing over the folly of the various bans being discussed. And putting ethanol in, oh dear!

Matthew
Posted on: 15 October 2002 by John Channing
quote:
Most super unleaded is well above 97 RON.


Maybe, but most* pumps in the UK that dispense super unleaded say 97 RON on them.
John
*All the ones I have seen.
Posted on: 15 October 2002 by Dev B
I hear what you are saying about your car being better with Optimax, but I suspect it's a bit like your hifi's when you think you have "upgraded" it but in reality it's "different".

1. Most petrol comes from the same refinery sources - there are not that many in the UK and the product is traded in the open market. So, for example, a Shell refinery blending Shell products may sell these on to Tesco.

2. Most fuel tank farms supply multiple sources, there are usually some main tanks - diesel, 95 RON, 97 RON unleaded, and 4 star unleaded. These sources go to the filling stations of any brand. One compmany does not have a monopoly over the UK's upply and distribution network. If Shell do anything to the product it would probably be additive (i.e after the fuel has left the farm) and would be no greater than the normal sample inconsistency in fuel.

It's worth mentioning that the mpg specs and mph specs for most car presume super unleaded, so if you have been using regular product, it might explain the performance upgrade.

But if you think your cars are faster with Shell Optimax who am I to argue?

cheers, Dev

ps. if I were being cyncial I would say you've been got at by the Shell Optimax marketing thing.

pps. you could argue that correct/high performance lubes make as much as a (or more) difference as premium fuels.
Posted on: 15 October 2002 by Bruce Woodhouse
Not logical Dev. You cannot say that we are indeed all noticing a difference but then that the fuel is all the same anayway.

If the RON value of Optimax is higher when measured in an independent lab, rather than by my right foot and the onrushing artic, then surely the petrol is not the same as that sold via Tesoc/BP and Joe Bloggs. A bigger question might be wether it is better than equivalent RON super-unleaded.

Bruce
Posted on: 15 October 2002 by Matthew T
John,

That is the minimum RON. The specs work that a minimum spec of RON needs to be meet and the MON has to be a minimum of 10 points below this spec and being harder to meet this tends to be the defining spec. This results in higher octane then is specified.

Matthew
Posted on: 15 October 2002 by Chunny Nochubb
I find this all very interesting, as I am about to become the proud owner of a car for the first time in 12 years, a 3 year old Saab 95 2.0t auto estate.
As the car was my former company car, I know that it has a bit of previous, which happened this August, after I filled up at a garage I don’t usually use and when we were on our way to France the next morning at crack of dawn when the engine fault light, lit up. The car managed to splutter on board the ferry and into France.
One French, one English garage and £400 later, with the fuel management computer reset (?) and a new air mass meter (?) on board, the car is nearly back to where it used to be although we are still suspicious about it.

I put it down to a bad dose of fuel. Having always used ordinary unleaded, which I think is recommended in the handbook, I have a few questions for the panel, and given that this is a Hi-Fi forum, I don’t think I need to apologise for my lack expertise in cars, which I know less about than Hi-Fi, (so that is very little indeed.)

1) Does anyone know if my car will be adversely affected by using this fuel?
2) I remember a few years ago that super-unleaded got a lot of bad press because it gave off high levels of benzene and probably other noxious items, on refuelling is this still the case?
3) In general does this fuel give off higher or lower pollutant emissions than ordinary unleaded?

Many Thanks.

CNC
Posted on: 15 October 2002 by Derek Wright
I asked your question in the alt.autos.saab newsgroup earlier today and so far the responses refer to earlier SAABs than your 9-5, the responses vary from tried but gave it up after a couple of tanks to yes it is great gives me 3-4mpg extra -

So no conclusive answer, _ suggest you chat to the local Saab dealer and see if they have any opinion.

----- Later news Wed am the NG reponses are very positive - reminding one that APC allows the RON to vary between 91 to 98 by adjusting the ignition cycle to optimise the engine performance

Derek

[This message was edited by Derek Wright on WEDNESDAY 16 October 2002 at 09:13.]
Posted on: 15 October 2002 by J.N.
Very interesting and informative responses.

I've had two tankfuls in my (BMW) MINI Cooper. I live in a rural area and was not able to make a Shell garage to continue the trial.

The car seemed to run more smoothly, with a tad of extra oomph.

Fuel consumption was about the same as regular, unleaded.

Optimax seems to be a bit cheaper than Super Unleaded. I'll give it another try.
Posted on: 16 October 2002 by Dev B
What you can all do for that 'optimax' experience is get a fuel additive (like that STP stuff in the good old days) and shove some in the tank just before you start to fill and just before you have finished filling (i.e twice during the refuelling procedure). Also change your Engine Oil for some Castrol GTX (synthetic) and get some Amsoil (sp?) for your gearbox and a free-flowing exhaust. It may give you the automotive equivalent of the Mana effect smile