What Octane Fuel Do You Use

Hi guys was just wondering what octane fuel and brands you use in your cars, I use Tesco’s momentum 99 in my golf Vr6 was thinking to use the same in my Fiat when I pick it up.

To my understanding unless you have a modded example and intend to drive it more aggressively/spiritedly as a result then it will run quite happily (and is designed for) standard 95-octane fuel.

The higher-octane stuff gives it more protection if you're stretching it say on a track day.

99 allows you to run more ignition advance, turbo cars are typically ignition limited. The Coupe has a conservative ignition map and cannot advance beyond it to take advantage of the increased octane (improved anti knock) so a non modified car will be OK on 95 or even 95 E10. I have always found however most cars feel like they run smoother with 98, the "but dyno" however is notoriously unreliable.

Out of interest, how is 97 octane fuel rated compared with either 95 or 99?

My VIS was remapped on 97. In hot weather it doesn't like 95 Ron.. It pinks a bit.. So I try and use either tesco 99 or 97.

Yep Super for me- for same reasons. It was remapped on Super. And I "feel" the difference when normal goes in if I am stuck for fuel.

Just looking at the new "modern" fuels that are about to be introduced in UK. Hope this won't impact he coupes out on the roads.

Regards

I changed to super / shell v-power, since regular petrol in The Netherlands all is E10 now.

From what I've read over the past few months I've been lead to believe E10 was not good for the the coupe. But is that really the case? Also on recent trips to Italy and travelling through Europe what is the situation there with fuel types available as and will it become a problem?

Or is the whole thing just overcome by running super E10?

Extract from European Automobile Manufacturers Association E10 compatibility list, Aug. 2018. From what I've read it doesn't suit turbocharged engines...


Fiat:
E10 petrol is cleared for all Fiat vehicles with petrol engines of Euro 3 emission levels or
newer, starting from model year 2000, except the following vehicles:
• Barchetta: 1.8 16V
• Bravo/Brava (182): 1.6 16V
• Doblò: 1.6 16V
• Marea: 1.6 16V, 2.0 16V
• Multipla: 1.6 16V
• Palio: 1.6 16V
• Punto (188): 1.8 16V
• Stilo: 1.6 16V (1.596 cm3), 1.8 16V, 2.4 20V

I have been running on E10 for years in Europe and haven’t had any issues at all.
There was a thread on this recently and others living in Europe report the same.

How is your octane number assessed? Is RON used, or MON? In OZ we use ((MON+RON)/2) I believe. I run 98 in my coupe, 95 doesn't seem to agree with it, especially in summer.

I've read nothing to confirm either way if E10 should be used on any coupé. Interesting to see that E10 looks to be used on coupé owners in Europe with no issues.


I cant remember what fuel I was putting in either coupés going to Italy. But is E5 available in Europe or is it only E10? I kept all my old fuel receipts from last years trip so I'll be checking them to see wether I have been running it on E10.

According to government E10 checker I can run my 1.4 turbo abarth on E10 but as you have posted above Simon the coupé ain't on that list.

We moved our cars over to E10 about 18 months ago without issue, a very slight increase in consumption is all we have seen. There is no reason E10 cannot be used in turbo cars in fact due to the greater knock resistance of ethanol it is perfectly suitable. On the Coupe the FRA (LTFT) figure might go a little positive to accommodate the small additional fuel requirement and obviously if the car has been remapped that's a different issue but a standard car will be fine. I'm running the Coupe on E85 (remapped) with considerable ignition advance that would be impossible with 98/99.

The issue isn't the mix - the ECU should be quite capable of handling that - but the longevity of the rubber/plastic components in the fuel system... which on older vehicles might not take to kindly to the extra ethanol in E10.

The cars listed all use the four-cylinder variant of the 20v/20vt engine... and the coupes are almost all pre 2000.

Approx 5-6% ethanol has been added to petrol since the late 90's. Adding another 4-5% is hardly going to cause a component problem now. Besides that, there are coupes in France that have been running on E85 for 10+ years without a single ethanol related problem.

The Fiat list like all the other manufacturers is simply commercial backside covering.

Regarding the overblown ethanol/rubber issue, France has seen a massive uptake in the use of E85, the 98 pumps are being replaced with either E10 or E85 and 98 is become more difficult to find in a lot of regions. The huge uptake has partly been driven by flex fuel vehicles and "flex boxes" but mostly by people discovering that they can fill their tank with a 50/50 E85/E10 mix without problem - including bangers going back to the 90's.

How about fuel additives I regularly use REDEX on my other car and will also use it with the coupe do any of you guys use anything similar.

I once put Redex in the spark plug holes (as recommended for an extra clean) and the smoke from the exhaust was unbelievable. It was worse than a James Bond smoke screen.

No harm putting it in the fuel tank though I would think. I used to use diesel booster in my old van and the difference was notiieable.

But generally I don't bother... Just super unleaded.

Reminds me of when a mate and I used to compete in a "Charity Rally"; we had a smoke maker where we could inject automatic transmission fluid directly into the engine pipe on the exhaust. It produced a lovely cloud of white smoke! We certainly had fun with it.