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Hi dont know if im posting in the right section BUT

Which petrol do you use?

are there any benefit or disadvantages?
 

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Higher octane is meant to be better/cleaner for your engine but performance wise not much difference, also some people say they get mpg with 97ron but if you pay more for it so it's not that much better.

On a standard car 95ron is fine
 

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ford quote 225bhp on 95 ron & 236bhp on high octaine. its a no brainer mate. you would'nt buy a racehorse and feed it chips would ya!
 

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QUOTE(stingy @ 30 Jan 2010, 01:11 PM) <{POST_SNAPBACK}>ford quote 225bhp on 95 ron & 236bhp on high octaine. its a no brainer mate. you would'nt buy a racehorse and feed it chips would ya!


Where did you read that?
 

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QUOTE(RichFST @ 30 Jan 2010, 01:15 PM) <{POST_SNAPBACK}>Where did you read that?

on this site, in one of the numerous threads on fuel mate.
not sure if its a 100% but it stands to reason if the ecu retards ignition timing when the intake temps are high, its bound to do the same for lower octain fuel. the ecu in the st is a very clever piece of kit!
surprsed this post has'nt already been locked. there really is loads of posts on fuel
 

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Point taken re the ECU. But, I've read many of these fuel related posts on here and can't remember one that mentions super uping output from 225 to 236BHP on standard tune. The general consensus seems that it can give slightly better fuel economy and better performance on mapped cars. Plus more pops from the exhaust. If it does then cool as thats what I usually stick in mine (VPower)


Anyway, this topic has been discussed 100s of times before so I won't prolong it!
 

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QUOTE(RichFST @ 30 Jan 2010, 02:20 PM) <{POST_SNAPBACK}>Point taken re the ECU. But, I've read many of these fuel related posts on here and can't remember one that mentions super uping output from 225 to 236BHP on standard tune. The general consensus seems that it can give slightly better fuel economy and better performance on mapped cars. Plus more pops from the exhaust. If it does then cool as thats what I usually stick in mine (VPower)


Anyway, this topic has been discussed 100s of times before so I won't prolong it!

i,ve read it twice in two different posts mate. but it could be wrong. still think there is bound to be an advantage on quality fuel, like the v power you use. i definatley notice it on mine.
will try & find the posts.
 

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type 'bp ultimante test' into google or youtube, its worth a watch. Compares bp ultimate with normal petrol using Focus
's

My car runs significantly better on Vpower. Did the same in my civic, even the 'purr' of the exhaust changed at idle.
 

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QUOTE(stevie g @ 30 Jan 2010, 01:21 PM) <{POST_SNAPBACK}>BP ultimate 79ron for me dude

Is that really cheap?


Tescos 99 or Sainsburys 97 is all that graces ST NUTs tank! Although when the need has arisen (Nurburgring and Isle of Man) i have run it on 95 and not really noticed a lot of difference!
 

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QUOTEIt seems to me that alot of people don't quite understand fuel and octane rating's,so iam going to try and explain aswell as i can.

the octane rating of fuel is its ability to resist combustion.
the higher the octane,the higher it's resistant.
a higher octane fuel will resist combusting before the spark plug ignites the fuel which can be caused by running high compression.
a lower octane fuel will heat up to much at high pressure and then combust at a moment which is not wanted losing power and cause potential damage depending what part of the stroke the piston is in when the fuel does ignite.
this is called pinking or pre detonation.This can be fatal to an engine of high compression.
When mapping a car,you will get a small increase in power,not due to the fuel giving you performance,but the adjustment that can be made to the ignition timing when using this fuel.

you will not get a performance advantage alone by just using higher octane fuel,this is controlled by the energy content of the fuel.
energy content is how much heat is released upon combustion.

by now you may have guessed,since the higher octane fuel doesnt combust as easy as lower octane fuel,it also takes more energy to ignite.

The difference people can feel with there standard car's is the fuel being burnt in a more controlled manor then with lower octane fuels.
that;s what makes it feel smoother.

if your car is pre detonating (knocking) then you will be losing power and effeciancy as the fuel could be burning as the piston is still rising,trying to push the pison down again.
 

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Kristel's quote was written by me for another forum were argumnts of what fuel is best etc.

to carry on from that,re the ecu and standard oem or near oem spec cars.
The ecu can only adjust the ignition timing so much,the manufacturers therefore map the ecu around 95 octane,as uk law states all cars to be sold in the uk must be able to run on 95.
Therefore the cars map is a compromise between 95 and upto 97/98 octanes.
anything above 97.98 you arent going to notice a massive difference,although there could be a slight diference going from say 95 because of the reasons explained above.
JDM cars are mapped based around 99 octane which is why they produce abit more power then BDM cars.
If you remap a BDM car using 99octane it will produce the sma epower output as a OEM JDM
But if you use anything lower then that then you could reck the engine,so thats the safety part manufacturers put in.
If you start upping the boost/compression then using hiher octane will be a must and not need,for the above reasons!
 

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QUOTE(stingy @ 30 Jan 2010, 01:11 PM) <{POST_SNAPBACK}>ford quote 225bhp on 95 ron & 236bhp on high octaine. its a no brainer mate. you would'nt buy a racehorse and feed it chips would ya!


Sorry matey but thats absolute trash(I know your only quoting from an old post)...Id better ring my insurance company and tell them that I may use super unleaded in the future and if I do will it put my premuim up!!!


The ST is officially 225 not 225/236 but only if you put super juice in it
 

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QUOTE(morty1970 @ 30 Jan 2010, 08:59 PM) <{POST_SNAPBACK}>Sorry matey but thats absolute trash(I know your only quoting from an old post)...Id better ring my insurance company and tell them that I may use super unleaded in the future and if I do will it put my premuim up!!!


The ST is officially 225 not 225/236 but only if you put super juice in it

yep mate. only quoting from another post i read. still run mine on bp ultimate though. definately better on a mapped car!
 
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