petrol differences

[imp124]

hi

i am looking at petrol brands and such at the moment.

we have all seen them

super, ultimate, high octane etc all claiming better engine performance, cleaner emissions and some more fuel ecomony.

What are peoples opinions on this topic and also peoples experiences.

Is it worth paying an extra 2 - 5p more a litre for the premium unleaded and what will it do to my car?

Does it really make the car more responsive?

Cheers

Steve

 

[joesouthgate]

Won't make any difference to a micra! unless its running very high compression (or turbo)

 

[curtis]

I only ever ran my last k10 on 97 or 99...

It did make a difference with the webers...im quite certain it did

Also keeps the engine less "coked up" as when i took the head off my ma12 there was hardly any carbon deposits on the valves etc...

 

[joesouthgate]

that had a skimmed head though, so would have had higher compression.

 

[curtis]

Get your head skimmed then

 

[joesouthgate]

nah i like 87 p a litre rather than over a quid!

 

[richj]

yeah the higher octane stuff can take more compression before detonating, so ideal for turbos or 'a skimmed head'. Aside from that point, I think some petrol is cut with 90:10 with ethanol. I would assume this would have a negative effect on power. I don't know though.

 

[Antony]

i thaught this is what raises octane to 99ron from the weak fairy liquid you can get in the states (87ron)
ethanol is what they run top fuel dragsters on, (methanol, ethanol and nitromethane)
the reason you cannot run pure ethanol in an engine (unless made for it) is due to its explosive nature, being pure alcohol, it would be like trying to start a lawnmover with mad dog 20:20...lol

 

[Arnold]

http://en.wikipedia.org/wiki/Ethanol#As_a_fuel

I think the recent fuel problems at Tesco etc was there was too much Ethanol in the fuel, and the newer cars weren't programmed to run on it. Older cars like K10's were fine. Does state there tho it's used in old rocket cars and is very volatile

 

[jabran200]

86.9p today so i'll stick to normal unleaded lol.

The higher stuff will be beneficail to stop det on high comp cars that were not meant for 95 ron all u.k made cars should be fine on 95. Japanes cars will benefit from 100/99/98 ron and turbo cars running higher boost.

It all depends on what fuel it was tuned on, i.e a car tuned with 95 will run fine on it but may make less power.

86.9p today so i'll stick to normal unleaded lol.

The higher stuff will be beneficail to stop det on high comp cars that were not meant for 95 ron all u.k made cars should be fine on 95. Japanes cars will benefit from 100/99/98 ron and turbo cars running higher boost.

It all depends on what fuel it was tuned on, i.e a car tuned with 95 will run fine on it but may make less power.

 

[richj]

yeah it says in the wikipedia article that gasohol is 90% petrol and 10% ethanol, giving 93/94 ron. Normal petrol is min 91 and premium petrol is max.95. I guess the ultimate high octane stuff must be premium petrol cut with ethanol to get the 98ron.

 

[imp124]

ok i like cheap(er) petrol but i just dont like all thease claims by petrol companys that their fuel lasts longest / is better for the engine WHAT EVIDENCE DO THEY HAVE TO BACK IT UP??? its as bad as fuel saver tyres, surely having them wont save fuel, you have to inflate them to the correct pressure also AND will it compromise on grip? a little off topic sorry but i just dont understand where thease companys get their evidence from to make these claims and where can i see the facts and figures?

cheers

Steve

 

[whipit]

ok i like cheap(er) petrol but i just dont like all thease claims by petrol companys that their fuel lasts longest / is better for the engine WHAT EVIDENCE DO THEY HAVE TO BACK IT UP??? its as bad as fuel saver tyres, surely having them wont save fuel, you have to inflate them to the correct pressure also AND will it compromise on grip?

To be fair the fuels can make a difference on the "correct" engine but the fuel saving tyres do make a difference by reducing rolling resistance without compromising too much grip. Rubbers not rubber.