Super unleaded - is it worth the extra cost?

Super unleaded - is it worth the extra cost?

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Discussion

john_p

7,073 posts

250 months

Tuesday 21st December 2010
quotequote all
pilchardthecat said:
That sounds like you're saying exactly the same thing as me in a slightly different way.

Cost wise, there is very little in it... that was my point.
Sure, but why buy an M3(etc) and then put 95 in reducing its power ?

Although I can understand in the current weather wink


Edited by john_p on Tuesday 21st December 14:38

davepoth

29,395 posts

199 months

Tuesday 21st December 2010
quotequote all
Luckily the S54 has a knock sensor - otherwise you would be running the risk of grenading the engine at high revs.

anonymous-user

54 months

Tuesday 21st December 2010
quotequote all
john_p said:
Sure, but why buy an M3(etc) and then put 95 in reducing its power ?
Realistically the opportunities for using "full power" in a modern high performance car are very limited indeed.

I stick some high octane fuel in the Vette for high days and holidays, but for day to day driving it makes no difference whatsoever. I've certainly not seen a reduction in fuel consumption sufficient to encourage me to pay the substantial price premium every time I fill the tank.

rhinochopig

17,932 posts

198 months

Tuesday 21st December 2010
quotequote all
jbi said:
whats your engine compression ratio?

Higher compression motors tend to require the higher octane stuff to prevent pre-ignition.

Most modern cars will automatically adjust for the petrol you put in but fuel economy and power output can suffer if you regularly use the wrong stuff.

Edited by jbi on Tuesday 21st December 13:32
Sorry but that's not true or bikes would be super only - and they're not.

Edited by rhinochopig on Tuesday 21st December 19:24

11110111

612 posts

200 months

Tuesday 21st December 2010
quotequote all
ok - so on my Civic Type R EP3 / 2004, do you think it will make much of a difference which I use?

Will I get an bigger YO! if I use the premium stuff?

TIA

sinizter

3,348 posts

186 months

Tuesday 21st December 2010
quotequote all
I get higher MPG from super unleaded, and therefore ends costing more or less the same as normal.

So, for the past 7 months or so, I have only been using super unleaded.

Drive Blind

5,096 posts

177 months

Tuesday 21st December 2010
quotequote all
I use SUL because I get about 10% better fuel consumption. Means I can go one extra commute to work before I have to fill up again.

RobCrezz

7,892 posts

208 months

Tuesday 21st December 2010
quotequote all
11110111 said:
ok - so on my Civic Type R EP3 / 2004, do you think it will make much of a difference which I use?

Will I get an bigger YO! if I use the premium stuff?

TIA
No doesn't make any difference on the Civic, unless you get K-pro and remap it to suit.



I would always use 99Ron on any turbocharged petrol car. The difference in price isnt much and most modern engines will take advantage, and even if they dont its additional knock protection.

pilchardthecat

7,483 posts

179 months

Tuesday 21st December 2010
quotequote all
john_p said:
pilchardthecat said:
That sounds like you're saying exactly the same thing as me in a slightly different way.

Cost wise, there is very little in it... that was my point.
Sure, but why buy an M3(etc) and then put 95 in reducing its power ?

Although I can understand in the current weather wink
Usually it's because the forecourt is really busy and I can't get to one of the 2 pumps that has Super, or if it's some stupid garage (BP are pretty bad sometimes) where the Super is 15p more than the other stuff.

As i said, you can't really tell under 5k rpm and i'm generally avoiding redlining the Z4M at the moment as it's a bit squirmy out there smile

I'd say i put 97/98 in it about two thirds of the time

funkyrobot

Original Poster:

18,789 posts

228 months

Tuesday 21st December 2010
quotequote all
Right, just checked my handbook. For the turbocharged L3 engine (which I think is the Mazda 3 MPS one) they recommend 98 ron. You can use 95 ron in these cars though according to the book.

My 2.0i Sport model seems to fall under the 'every other petrol engine' section which is below the turbo engine section. This simply says '95 ron or above'. Therefore, i'm guessing 95 is fine but I can use higher octanes if desired?

Thanks. smile

CaptainSensib1e

1,434 posts

221 months

Tuesday 21st December 2010
quotequote all
I thought all cars sold in the EU had to be able to run safely on 95 RON? Of course they may run better on higher octanes.

RobCrezz

7,892 posts

208 months

Tuesday 21st December 2010
quotequote all
funkyrobot said:
Right, just checked my handbook. For the turbocharged L3 engine (which I think is the Mazda 3 MPS one) they recommend 98 ron. You can use 95 ron in these cars though according to the book.

My 2.0i Sport model seems to fall under the 'every other petrol engine' section which is below the turbo engine section. This simply says '95 ron or above'. Therefore, i'm guessing 95 is fine but I can use higher octanes if desired?

Thanks. smile
Oh right, if yours isnt the turbo MPS, then dont bother. Maybe once in a while for the cleaning additives, but there wont be any noticeable performance difference.

AJB

856 posts

215 months

Tuesday 21st December 2010
quotequote all
funkyrobot said:
Right, just checked my handbook. For the turbocharged L3 engine (which I think is the Mazda 3 MPS one) they recommend 98 ron. You can use 95 ron in these cars though according to the book.

My 2.0i Sport model seems to fall under the 'every other petrol engine' section which is below the turbo engine section. This simply says '95 ron or above'. Therefore, i'm guessing 95 is fine but I can use higher octanes if desired?
Exactly right. So the turbocharged one is optimised for 98 ron. It can cope with 95 but only by reducing economy and power in the process, so probably not saving any money overall and definitely losing performance.

Yours is optimised for 95 ron. Using 98 might very slightly increase power/economy (if it's got a knock sensor) - but only very slightly, and not certainly not justifying the extra cost of the fuel on financial grounds. Or using 98 might very slightly reduce power/economy (because the 98 ron fuel has got slightly less energy in it).

For either engine, you won't do any harm at all by using higher ron fuel than specified (other than to your wallet).

citizen_smith

286 posts

185 months

Tuesday 21st December 2010
quotequote all
My car is a 05 corsa 1.8. the manual says use 95 or 98. would I benefit from using 98?

Chris71

21,536 posts

242 months

Tuesday 21st December 2010
quotequote all
There are two seperate issues here.

One is the octance rating itself. If you have a car calibrated specifically for 98 RON then you risk seriously damaging it by detonation (or 'pinking') if you run it on lesser fuels. Similarly an increasing number of cars have knock sensors, which should be safe to run on 95 RON or below, but won't perform as well as they could.

Second is the various additives in the fuel. The high performance fuels have all sorts of additional components which enhance the long- and short-term health of the engine. Their effect is harder to quantify, but they are there for reason, they're not just marketing gimmicks.

Compo_Simmonite

391 posts

187 months

Tuesday 21st December 2010
quotequote all
My Smart Fortwo (700cc, twin plugged, turbo & intercooled as standard !) will run on the cheapest fuel but I get better mpg on super unleaded that justifies the additional expense. SEEMS a little smoother as well but cann't comment on any improvement in performance.

Paul H

Edited by Compo_Simmonite on Tuesday 21st December 17:56

wifiwupding

176 posts

161 months

Tuesday 21st December 2010
quotequote all
my ignis sport requires 98+ but i was running low in the middle of nowhere and had to top up with 95 and almost instantly noticed a difference, the revs rise and lower much slower so its actualy easier to get smooth gearchanges but the engine itself felt and sounded rougher but i didnt realy notice any difference in performance

marcosgt

11,021 posts

176 months

Tuesday 21st December 2010
quotequote all
My vRS Skoda Octavia seemed to run a little better and go a little further on super unleaded, but it doesn't make a scrap of difference in the RX8 and didn't seem to in the Puma I had before the Skoda.

M.

retrorider

1,339 posts

201 months

Tuesday 21st December 2010
quotequote all
100 will be in the U.K at some point to confuse the issue even more...

Sour Kraut

45,899 posts

189 months

Tuesday 21st December 2010
quotequote all
retrorider said:
100 will be in the U.K at some point to confuse the issue even more...
The on-site fuel station at Snetterton sells 100 (probably at other tracks too)

I wonder how older cars like my E36 track car would 'manage' a higher octane? Or would it be a worthless exercise?