Hi!
I just recently purchased my first 2.0 MX-5 NC! I’ve been putting regular unleaded into the tank but i noticed on the fuel filler cap it said that i should be putting the more expensive premium unleaded in. Can anyone notice the difference between the two fuels?
Thanks!
Does it give the octane number? In the US and some other markets they have a 91 octane fuel grade called Regular. Over here we only have 95 and 98+ grades (regular and super). In my ND it tells me to use 95 octane gas as a minimum which is our regular.
I thought about putting Super unleaded in mine (BP) the other day but changed my mind when I saw the price of their standard 95 Ron @£1.19 pl. I would be guessing their Super 98 RON would be another 4-5 ppl more.
Now me being a tight so and so I drove straight past and filled up with some 95 RON standard Asda stuff @£1.14. (Asda don’t offer Suoer 98 RON fuel) My fuel label says 95 RON is suitable.
Te5c* do momentum super unleaded . . . .
I suppose we all use what we are happy with.
I tried keeping a mileage diary back in 2015 for a month using shell nitro. I managed to get 32mpg. The standard stuff returns 27mpg. I now use shell nitro all the time and still getting the same figures. About 10% extra cost, but much more than 10% extra mpg. The more expensive fuel is cheaper. Still doesn’t sound right when I say it out loud.
I went onto BP Ultimate a few months ago and noticed an immediate difference in performance and economy. Read the owners handbook, it says using regular unleaded is okay but performance will be slightly less. I haven’t tried Shell V power yet but I guess there isn’t much, if any difference between them. To my way of thinking the extra 10p on the cost is well worth it.
When we took our 2006 2.0 nc to BBR for some mods, they said our engine was in exceptionally good condition for it’s age.
It was making exactly 158bhp before the mods, the same as the day it left the factory!
We have always put BP Ultimate in the tank, and BBR recommend this for MXs which they modify.
So, slightly better fuel economy, a very clean and healthy engine, and only a few extra pence per litre. As this is our fun car, and not our daily commuter, we think it’s worth the extra.
I use nothing but Shell Optimax in all my cars as I feel they run better and the smell does not make me feel sick when I fill up like all the cheap supermarket fuels I don’t know what they put in theirs but I guess it’s cheap for a reason, also it is not only good for the engine but good for the whole fuel system apparently
And the best part is the nearest Shell garage is 6 miles from me.
Thanks guys for your responses! Next time i fill up i will be going for the more expensive stuff! It sounds worth it! Definitely if it makes the engine last longer! And as one of you said, its just a few more pounds!
Don’t forget to run the fuel tank down as low as you dare, to make sure you get the best benefit of the full tank of new fuel straight away - although anything left of the old stuff will be depleted with subsequent fill ups.
I believe (though have no specific knowledge) that the ECU will adapt to the different RON level of the particular fuel so it may take more than one tank through the system to see any results.
I think you have to be pretty careful not to introduce a placebo effect by driving differently without realising it and having an effect on MPG that way.
I am tempted to put a few tanks through the ND though and see what happens, it has a very accurate MPG reporting feature.
On Saturday I managed 44.8 MPG on a 50 mile journey, half of which was driven in a quite (ahem) warm manner, outstanding
I don’t think ECUs are designed to “adapt” to a higher quality fuel, as such.
However, if the engine is equipped with a knock sensor it will retard the ignition to avoid piston damage (resulting in reduced performance) if poor quality fuel results in detonation.
That’s why manufacturers specify a minimum fuel grade.
Alway try and fill up with Momentum, never used any regular unleaded it my 2.0 sport since I’ve had it, and it seems a very happy bunny.