I started off on 99, then my mileage went up significantly so I dropped to standard. Since lockdown I'm back on 99 as I'm not spending anywhere near the same (100+ miles p/day vs working from home).
Is there a big difference........ No. Is there a minor improvement on 99........ I believe so.
Tesco Momentum 99 ron...I've used it for years, my bike was the biggest surprise the pick-up was noticeably sharper.
I remember reading a post somewhere that a tunning company run a stock Focus ST on 95 ron for a couple of thousand miles dyno'd it then switched to Momentum the difference was +20 bhp, how much you will get with a GT is anybodys guess without a dyno run...how about doing that and post the results.
Standard Kias will run problem free on 95 unless it says otherwise in the user manual.
A motorcycle, possibly with carburetors and different compression ratio could be quite different to a standard car.
99, or at least some, apparantly has less or no ethanol.
Where I buy fuel, 95 is often on special at about 15-20% off the highest prices. 99 is never on special and is therefor about 20% more than I need to pay.
No extra milage can compensate for that.
I think it was Fifth Gear car program that did a test on the relative merits of higher RON fuels a few years back.
As Jack Daniels suggests, the conclusion was that your average everyday commuter car wouldn't see a difference.
However if you have a "sporty" mobile, it probably will have a better performance as the mapping can take advantage of the higher RON fuel
The caveats were it takes a few hundred miles to really notice and the relative merits of higher RON sometimes having better detergents wasn't really considered.
I guess it simply comes down to you pays your money and makes your choice.
In my normally aspirated 1.6 multi point injection Venga automatic, I'l be sticking to 95 RON as it is in no way sporty.
Since I did the Racechip and panel filter changes I been using Momentum 99 when I can. I don't have a Tesco locally so it's an excuse for a drive especially with petrol prices a bit lower at moment. I did notice a change initally, but overall the car feels a lot zippier. I love watching the torque gauge hitting the max mark when I floor the gas pedal. Like a strongman machine at the fair. If only a bell rang.
At the start of the first lockdown I noticed prices of petrol went down quite a bit so since I have filled up a couple of times with 99 rather than the usual 95. It could be my imagination but I felt the car a little perkier and slightly better economy. Not put it to the test on a longer run, I have only done 1200 miles this year!!!
Shell V-Power, I used to use what ever I could be bothered putting in but car started acting up using cheap supermarket fuel, earlier this year I went on a long trip I had used some crap from Morrisons and the car ran like a bag of spanners for the whole trip, hesitating/lumpy idle, since then I've used nothing but V-Power and it's been fine since.