Who runs RON98 in their VRX?

[Graham]

I usually put 98 in my car every three tanks, so 91, 91, 98, 91, 91, 98.

But since getting the stage 1 RPW tune I've been advised to only use 95+ so I think I'll just keep using 98 from here, it's usually only 3 cents extra on top of the 95.

[aussie027]

After talking to David 91 is fine ,wont do any harm at all, 95 is better, no need to be too obsessive about it. PM me or call if you want details Graham.

[SIR-VRX]

Yes tryg, a lot of cars do have knock sensors etc but not all are smart enough to use them haha

[VRXCESS]

Thanks for the responses.

Since I am going to be running RON98 from new. Would anyone be interested in me posting my mileage per tank for information purposes for the next 4-6 weeks?

I do a fair bit of city driving and minimal highway driving. My VRX is a M/T running the standard tyres.

My run each week is pretty consistent and I was getting 450kms on average per tank running RON91 in my previous car, which was a '97 Mazda Astina (4cyl 1800cc) with an extractor kit. This would last me about 10 days of driving and would cost me about $50-$55 per tank.

For my reference should I expect good or crappy fuel efficiency during the first 1500kms?

I have read the thread and linked article on the breaking in period of the engine and am not "babying" the car during this period. I have already taken it out this weekend for a good run along Eastlink / Monash freeway and up to Mt Dandenong and made sure to give it quite a few spurts along the way through the rev ranges.

[cyssero]

its not just our car that adjusts mapping to knock sensor output, its just about all (unless you have a car made in India or something)...

The Tata Indica, the super successful car in the hatchback segment. The 32bit microprocessor MPFI engine gives great performance and it also has knock control sensors providing great fuel efficiency.

Source

Not bad for a car that costs the equivalent of $6200 AUD.

[tryg]

I stand corrected.... now it seems all do !!

[cyssero]

Guess you can confidently say they all do now though

[Bandit]

Since I am going to be running RON98 from new. Would anyone be interested in me posting my mileage per tank for information purposes for the next 4-6 weeks?

Fuel economy will not be as good as it can be early on. But post the info if you like, even if it's to see the numbers get better over time.

I use BP 95 then every 4th fill is 98 for the detergent in it.

Don't notice any difference in mileage or smoothness. I think the issue there is that the car rarely goes below half a tank before it gets filled up, so there's always a mix of fuel in there.

The VX Commo I have drinks 91 only (ethanol free of course) and loves it. No need for the fancy stuff in an Ecotec 6 powered vehicle!

[mitsfan]

I have been using Shell Optimax since new in my VRX because it made a big difference when I switched from standard unleaded to this premium petrol in my previous car (Magna Altera). In the Magna I experienced a dramatic improvement in responsiveness and smoothness, that continued to improve for several weeks, probably in part due to the detergent cleaning properties of the Optimax.

I deliberately use the same brand of premium unleaded consistently in the Lancer so the VRX motor electronics dont have to keep retuning to varying petrol properties (resulting in less than optimal combustion of the fuel).

However, when I started using premium unleaded about 3 years ago there was a much smaller price differential then there is now.

It seems that the absolute margin increased when the price per litre dramatically increased a year or two ago (reasonably maintaining a similar relative differential), but then they failed to decrease the absolution price difference again when the price per litre dropped. The absolute cent difference seems to have increased actually!

[blade888]

I've been using 98RON since my car's been modded. But there have been times where I have been forced to fill up on 91 because it was on a really expensive day and needed fuel (running on next to empty) or the fuel station didn't have it avail at the time.

Before I modded the car I used 98RON a couple of times but didn't notice any real difference.

But since I have modded, I do notice the difference especially on the low-mid range torque. As well as fuel econo as well over all.

But as others said it's not the cheapest option and that's true. But the fuel takes better care of your engine in the long run and would reduce long term maintenance costs. So it might equal out in that aspect. But we'll all have to see once the cars get older.

[VRXCESS]

I have had the car now for 3 weeks and am beginning to notice better fuel efficiency.

The car has done about 1300km and has had it's first service today during which I made sure to swap out the oil and get a new oil filter.

So far my best avg. fuel consumption has been 6.6L/100km. My 3rd tank of fuel yielded about 550km, which is not as good as it could have been as I am still a little lead footed while I run the car in. I also suspect that the fuel tank is now fully purged of the RON91 the dealer would have put in the tank for delivery.

I have also just dropped a HKS Super Hybrid dry air filter in, which seems to have yielded a subtle performance boost. As to what it will do to fuel efficiency is anyones guess.

In my opinion it's still too early to tell if I'm getting an appreciable benefit from using the RON98.

[timd]

I've run 98 in my 2L from new..... some might say it's a waste of money, but I seem to get consistatly better mileage than what others quote.... I've done Canberra to Coffs Harbour in one tank..... running on empty by the end, and I was driving at night - so way less traffic to slow me down. but 800km is still pretty good I reckon....

[ofey]

Just for everyone to know, I run a mixture of grades. I've even done E10, 95, 91, 98 but usually it's Caltex or Shell Unleaded. I usually fill to the very brim. So it's a real full tank. I also use Liquid Moly fuel additives every 5000 km.

My car ran out of petrol on Friday and stopped in the middle of Johnston Street Carlton.

My final reading on the odometer?

651.6KM off a single tank for a:
1. CVT
2. sound deadening all over
3. RA Intake
4. K&N Air Filter
5. RPW flash tuned

is pretty damn good.

[Graham]

my last tank I got just under 600k's but it still had about 7L left in the tank.

Running 98 with RPW flash tune

[tryg]

Not all Shell stores sell it, but I found E10 fuel is 95RON. That is remarkable for the price savings.... I am sure most of you shun the E10 (due to ethanol).

I am not finding any additional benefits from 98 over 95.... exactly the same extra-urban fuel consumption figures... I meticulously maintain all my fills on my iPhone application to manage fuel. Seems the 95 runs the same as 98, in my case.

Obviously would be very different on others' cars, with different driving styles, weight, mods etc..