Whilst working on a new BP petrol station the other day i noticed that they were introducing a new unleaded called bp ultimate claiming that it was "high performance with less pollutiuon". does n e one know if this is there answer to optimax?
this would be handy for me seens the nearest shell garage is 20 miles away!
i\'ve noticed such a difference between feuls in my FD and optimax is by far the best, i just need a shell garage more local cos it costs me about £15 just to get to the garage and back!
:confused:
Pretty much old BP super just rebranded.
Lee
that suprises me cos they seemed to be making a big deal out of it! then again there probably trying to boost sales cos optimax must have taken the shine off of super!
Got it in one :)
Id use it, but seeing as Shell is closer I tend to just go there unless they are out.
One BIG difference...
BP Ultimate 97 RON
Optimax ~98.6 RON
Same price. You pay your money and take your choice. Shell all the way for me.
Iain
QuoteOriginally posted by J4P RX
Pretty much old BP super just rebranded.
Lee
The Ultimate name has been around for years in the USA as Amoco Ultimate; BP bought Amoco in 1999-ish. BP Ultimate was launched in Australia a while back and then in Greece (where it has 100 RON :eek:). It\'s a highly additised fuel, so extra RON isn\'t the only benefit.
I don\'t know enough about the dynamics of a rotary to comment but in an Otto engine the major benefits come if the timing can be advanced - the higher RON of fuels like Optimax, Ultimate and other supers allows a later ignition timing without fear of pinking/pre-ignition. Modern engines with dynamic ignition control will automatically eek the best out of these fuels. However there will be a longer term benefit to any engine in terms of fuel system integrity and inlet valve cleanliness.
Perhaps rotaries have a better apetite for higher RON? I don\'t know how ignition timing relates to power on these.
If you\'re interested BP also do an Ultimate diesel with a cetane index around 10 points higher than normal. Definite benefits to be had there.
i\'d use it only if i was on fumes (or in the mondeo :eek: lol) as optimax is king still in the RON stakes so BP have still lost out on performance sector but then we know it\'s more of a rebranding on all their unleaded rather than a better fuel on offer for those that want it like shell IMO.
Si
Weasley...
Most rotaries are imports and are mapped for the higher ocatne levels found in Japan. Running them hard on 95 RON petrol increases the risk of detonation which will kill a rotary in pretty short order. Using SUL is obvioulsy closer to the RON that the ecu is expecting and @ 98.6(ish) Optimax is closer still. If BP were to start selling their 100 RON fuel here I\'d swap over to them no worries!
Some people go to the lengths of adding octane booster to every tank, some just for track work.
If a car\'s re-mapped here in the UK the tuiner should be able to advise on the required fuel type and benefits of additives.
Iain
totally lost now! whos ron?
i\'ll just stick to driving my 20 miles to shell untill i see the rotarys queing at BP!
is the higher ron the higher octane level?
and is the new "ulimate" the 100 ron?
No the 100 ron is in Greece. Ours is just 97.
Lee
(http://www.stopstart.freeserve.co.uk/smilie/teach.gif) & yes RON is sumin like Research Octane Number.
Si
unless you are in the US who use Road Octane Number ... which just to make it even more confusing is different from the Research rating !
well someone better get on the dog n bone and tell BP
to get there 100 sh_t over here!!!
Thanks for running this thread chaps because l wondered about this how good this fuel is fuel , anyone know the rating of the other \'super\' fuels.
Many years ago l had a chart that explained fuel \'rating\'s from around the world and all the different terminologies of the RON word!! .
My point is that it could be that RON here may well be more potent that we think.
Also we have more than enough members from all corners of the world to find out what quality of fuel they use.
QuoteOriginally posted by clive
My point is that it could be that RON here may well be more potent that we think.
The key comparison would really be between Japanese RON and UK as most of our cars are tuned for the JAP 100 RON fuel.
Whilst it\'d be great if we found out out 97 RON was equivalent to 100 RON in Japan I seriously doubt it. It\'s usually the americans who use a different scale to the rest of the world. I\'m sure we\'d have heard something to do with this before aswell. Plus: there\'s no way we\'d have something better over here, htat\'s just sods law!
Iain
Let me explain further, given that this is my area of profession (well, related).
RON is Research Octane Number. It is measured by running a fuel on a special engine with variable compression ratio. You increase the compression until the engine starts pinking, then you see what the compression is. You then test mixtures of reference fuels with known amounts of iso-octane in them. The reference fuel which gives the same result as the test fuel determines the result - ie if the reference fuel had 95.5% iso-octane in it then the matching test fuel would have a RON of 95.5 (probably rounded to 96). Does that make sense??
Another common test is for MON, that being Motor Octane Number. This uses the same basic test as the RON test but has fixed ignition timing (compared to the variable ignition timing of the RON test). Therefore it is more severe, causes earlier pinking and therefore gives lower results, so a fuel\'s MON is always less than its RON.
The MON is thought to be more realistic for road use, so in America what they do is take the average of the RON and MON and call it the "Anti-knock Index" or AKI. You may also see it written as the R+M/2 octane.
Therefore American pump octane numbers are lower than the equivalent in the UK (and most of the world). However, RON is RON wherever it is used, so Japanese RON is the same as UK RON. Japanese 100 RON fuel is indeed more \'potent\' than our 97/98 and goes some way to explaining why JDM cars often offer higher power engines than their European equivalents since the engines are mapped and tested on the 100 RON fuel.
Why octane? Iso-octane as a chemical is highly resistant to pre-ignition, so the more the better. A 95 RON fuel doesn\'t actually have 95% iso-octane in it but it has an equivalent level of knock-protection. You can get >100 RON by the use of additives which improve the knock resistance to be better than a 100% iso-octane fuel.