Talk Morgan Forums Community The Malvern Arms Is it worth using super unleaded in a Plus 4?

Have tried searching to see if discussed before but couldn’t find it.
I know it has higher octane content compared to normal petrol and supposedly other additives to keep engine clean but is it worth the extra cost? Do you get any better performance overall that a duffer like me would notice?
Thanks
HB

I seem to remember others have commented about the relative ethanol contents of different grades. Personally I always use the higher octane or 'ultimate' ranges of both diesel and petrol as I have convinced myself that they offer better mpg and performance. As all my mileage is nearly all for pleasure these days and is relatively low for both my cars the extra cost is not really a factor in my choice though.

Absolutely, the car will feel twice as good.

Just the same as when you buy perfume for your wife, the most expensive ones work far better than the knock offs which smell exactly the same.

Not really relevant to you but I have found the super unleaded gives better performance in my trad +8. There is a stretch of road near us with a gradual incline. With my foot to the floor standard petrol results in knocking. With super there is no knocking, it just flies! May be I could get the same result by tinkering with the timing but it is easier to 'pump the super'

Depends on the engine in the car, but if its a modern one then it will have anti knock sensors which will allow you to use the normal 95 octane stuff. Many magazine tests have shown the benefits of the hiugher octane fuel in a modern engine not specified to require higher octane to be marginal or non existant

I always use a premium diesel because with my previous car, which did not have a particle filter, I had noticed much less black smoke on hard acceleration. In fact I had complained to the dealer about the smoke under acceleration and was told "They all do that". My preferred diesel is Q8 Hi-Q and other than a cleaner exhaust I think I get a slightly better consumption. Given the obviously cleaner emissions I have even wondered why this grade of diesel is not obligatory for diesel cars.

For the Morgan I often use the premium super but I really don't notice that much difference. I generally avoid the E10 petrol which is commonly available in France but I do occasionally use the E5 fuel which is available locally.

I am convinced that high ethanol fuels are not really suitable for use with older components, such as fuel lines etc, that where not manufactured to be resistant to ethanol.

Absolutley...only use super unleaded in my P4SS.

In my previous 4/4 Sigma engine after having the ECU remapped by Cain of Wolf Performance the engine used to "pink" on normal unleaded but this was cured by using super unleaded.

It also made a noticeable difference pre remapping on acceleration and drivability.

So yes ...your favourite car will thank you for using the best !!!

As has been said, any car engine with knock sensors and an adaptive ECU will benefit from a higher octane fuel. Also, higher octane fuels have better additives which help keep the fuel system clean: this is very important with cars that have throttle body injection.

The fuel info in the AMG suggests 98 Octane. The handbook states that both 95 and 93 Octane may be used, but there will be a loss of performance.

The BMW doesn't seem to care, so it gets 95 Octane and the Morgan gets premium unleaded.

On the old E Coupe, which had a 3.0L Diesel using premium diesel gave a 10% improvement in fuel economy. No idea why.

+1

Like others I always try to put premium fuel in the Mog

And I try to always fill up with Shell’s super unleaded because one of my best friends designs petrol filling stations and he told me a few years ago that only Shell stations in the uk have the best moisture free tanks