Fuels - Don Vito
Are the new range of Ultimate and Optimax unleaded fuels safe to use on ALL vehicles (obviously apart from those that require diesel or leaded!)?

If so, do they deliver the additional efficiency and performance that they promise and are they worth the extra pennies on the litre?
Fuels - madf
Yes
No. not always.

madf


Fuels - Roger Jones
Don

Do a Forum search and you will find many threads on this topic, none of which appear to be conclusive. However, HJ himself seems pretty convinced about the benefits of Optimax, at least for engines with high compression ratios if not for all. I happen to believe him.
Fuels - springyboy
I run an old car with a high compression ratio. Prior to Optimax I was getting pinking under load and resorted to adjusting the timing to try and minimise it. I was suspicious about the marketing claims of Optimax but tried it. From the first tankful I was convinced, the difference was clear and I've used it ever since. Timing is reset to manufactures spec and engine runs beautifully. guess because my car does not have the modern emgine management systems that can adjust the timing in order to avoid pinking I get more benefit than a newer car might. Optimax also claims better detergents etc, and looking into my carb and engine I am very pleased with how clean it seems.

Try it and see what you think
Fuels - Mapmaker
Just the sort of car that will benefit from the higher octane rating.

But I'm afraid that I'm not going to be buying Optimax just to subsidise your use of it. Sorry!

Other benefit of Optimax seems to be that you get top trumps cards that school children love.
Fuels - Ford Dagenham
Hi

That sounded a bit heavy.

What do you mean iam not going to buy optimax to subsidise his use of it?

One benefit i and my wife has noticed is easier starting and slightly smoother power.

This occurred in a mondeo and mk3 fiesta.


(iam not a mechanic)

Martin Winters
Fuels - Mapmaker
Slightly TIC, but:

On the basis that opinion is that certain high performance high compression engines often with automatic variable retardation may benefit from the higher octane rating of Optimax. (Not even Shell can come up with scientific backing for their more outrageous claims!)

Certain high performance h c e o w a v i r (as before!) may not benefit.

Most other cars would obtain no benefit from the highter octane rating (unless perhaps you changed the retardation manually).

Shell's advertising suggests that even your lawnmower runs better on it. This is so that lots of people use it in their Trabants, so it is worth Shell's while to stock it.

Therefore, Trabant users obtain no benefit, yet subsidise the distribution of Optimax for the benefit of the few users of high performance h c e o w a v i r cars. Simple really!