Ohh no, another fuel question (RON) - Mercedes Benz SLK Forum

AMGs For those high performance Mercedes-Benz R170-SLK 32/R171-SLK 55/R172-SLK 55 cars tuned by AMG -

 3Likes
Reply
 
LinkBack Thread Tools
#1 Old 02-11-2013
Registered Users
 
Swagman's Avatar
 
Join Date: Oct 2010
Location: Northampton, UK
Vehicle: 12' SLK55 AMG
Other Toys: 15' HYUNDAI SANTA FE
Posts: 921
Country:
Chats: 0
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 36 Post(s)
Thanks: 77
Thanked 135 Times in 99 Posts
Garage
(Thread Starter)
Ohh no, another fuel question (RON)

So, reading the handbook on my new 55, it tells me to fill up with 98 RON

Researching the various 'big name brands' here in the UK I find that:

BP Ultimate : 97 RON
Total Excellium : 97 RON
Esso Energy : 97 RON
Texaco Super : 97 RON
Shell V-Power : 99 RON

Not sure about the supermarket chains, but feel I should be putting in the juice from a main player..

So what's a guy to do?, there is no 98 RON, will the 97 do the job, or should I go over 98 for the V-Power 99..?
Swagman is offline  
Sponsored Links
Advertisement
 
#2 Old 02-11-2013
Banned
 
Join Date: Mar 2011
Posts: 7,812
Country:
Chats: 0
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks: 681
Thanked 961 Times in 704 Posts
I only have the 350 but I run it on supermarket plain unleaded. Personally I think 99 would be a waste of money. I cant see 97 doing any harm
JonB is offline  
#3 Old 02-11-2013
Banned
 
Join Date: Mar 2011
Posts: 7,812
Country:
Chats: 0
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks: 681
Thanked 961 Times in 704 Posts
the 350 manual says minimum of 91 ron !!!!
JonB is offline  
 
#4 Old 02-11-2013
Registered Users
 
Riverside Red's Avatar
 
Join Date: Dec 2012
Location: Darlington
Vehicle: SLK 55 AMG 2012MY
Other Toys: 2015 Solar Yellow Lotus Elise S, 2014 Audi S5 Sportback
Posts: 71
Country:
Chats: 0
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Thanks: 3
Thanked 2 Times in 2 Posts
Garage
After 6 years with an S2000 needing SUL, my personal choice for best performance and running would be either Shell V Power or Tesco Momentum 99. That's also what I'm currently using in my R172 SLK55 too, but haven't had a chance to give it some beans yet due to the crap weather.

Would really steer clear of BP, the S2000 ran very poorly on their 97 RON stuff.

My motto is always best fuel and best oil you can afford, athletes don't eat rubbish do they?

RR
Riverside Red is offline  
#5 Old 02-11-2013
Registered Users
 
Swagman's Avatar
 
Join Date: Oct 2010
Location: Northampton, UK
Vehicle: 12' SLK55 AMG
Other Toys: 15' HYUNDAI SANTA FE
Posts: 921
Country:
Chats: 0
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 36 Post(s)
Thanks: 77
Thanked 135 Times in 99 Posts
Garage
(Thread Starter)
Quote:
Originally Posted by Riverside Red View Post
My motto is always best fuel and best oil you can afford, athletes don't eat rubbish do they?
Agreed, after spending so much on the car, i'm not trying to save a few pennies on each tankful

It's just sooo confusing with them all being 'super unleaded', and ranging from 97 - 99 RON..

I suppose if the handbook says 98, and we assume that they mean this is the minimum grade required, it can only really be V-Power or Tesco's Momentum, that I need to stick in it..

The reason for the question is that, I went to a specific garage on Saturday to fill up (Esso), as I was going to Maidstone shopping anyway, and then when I got there and saw it was only 97, I only put a tenner in, and drove away in disgust...
Swagman is offline  
#6 Old 02-11-2013
Premium Member
 
ZeroZero's Avatar
 
Join Date: Sep 2009
Location: Coventry
Vehicle: 2005 SLK 55 AMG
Other Toys: Two Smart ForTwo(carbon footprint. offset)
Posts: 1,695
Country:
Chats: 0
Mentioned: 105 Post(s)
Tagged: 0 Thread(s)
Quoted: 257 Post(s)
Thanks: 15
Thanked 225 Times in 181 Posts
Hi Swagman

After the last post on this subject i have revisited the super-unleaded(Tesco) pump this last fill up , Only 3/4 of a tank to full so im keeping with s/unleaded for the next 2-3 tank fulls & see if it improves the way the car runs .

Cheers

Andy
ZeroZero is offline  
#7 Old 02-11-2013
Registered Users
 
GeeJay's Avatar
 
Join Date: Jan 2009
Location: North-West Blighty.....
Vehicle: '16 C250d AMG Estate Premium+ Designo Hyacinth Metalic
Other Toys: Guitars... :-) Formerly '08 SLK200 6sp Palladium
Posts: 5,134
Country:
Chats: 91
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 70 Post(s)
Thanks: 652
Thanked 793 Times in 574 Posts
Well, I think some of you know what I think.....
JonB likes this.
GeeJay is offline  
#8 Old 02-11-2013
Registered Users
 
Riverside Red's Avatar
 
Join Date: Dec 2012
Location: Darlington
Vehicle: SLK 55 AMG 2012MY
Other Toys: 2015 Solar Yellow Lotus Elise S, 2014 Audi S5 Sportback
Posts: 71
Country:
Chats: 0
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Thanks: 3
Thanked 2 Times in 2 Posts
Garage
Hi performance engines normally have automatic knock detection so lower RON fuel, even 95 won't do any damage for a couple of tank fills if SUL isn't available however I wouldn't like to run a high performance car for an extended period on low octane fuel.

I think the difference between 97 and 98 isn't too great, however most people I know who run high performance cars use V power and momentum, perhaps because they have the highest octane rating.
Riverside Red is offline  
#9 Old 02-11-2013
Registered Users
 
Join Date: Apr 2011
Location: North West UK
Vehicle: 2006 SLK55AMG
Other Toys: PlayStation3
Posts: 124
Country:
Chats: 0
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Thanks: 4
Thanked 3 Times in 3 Posts
Its never good to run on lower octane for your car for a long period. Anything above and the car will love you for it.

But if you happen to get caught out and no high octane fuel around, fill up a tenner's or so worth with either normal 95 or 97 and drive to a station with the high octane stuff.....no WOT!

TBH, felt no significant difference between V-Power and Momemtum 99. Just like to use VP more for its cleaning agents.
triple bogey is offline  
#10 Old 02-12-2013
Registered Users
 
GeeJay's Avatar
 
Join Date: Jan 2009
Location: North-West Blighty.....
Vehicle: '16 C250d AMG Estate Premium+ Designo Hyacinth Metalic
Other Toys: Guitars... :-) Formerly '08 SLK200 6sp Palladium
Posts: 5,134
Country:
Chats: 91
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 70 Post(s)
Thanks: 652
Thanked 793 Times in 574 Posts
Quote:
Originally Posted by Riverside Red View Post
Hi performance engines normally have automatic knock detection so lower RON fuel, even 95 won't do any damage for a couple of tank fills if SUL isn't available however I wouldn't like to run a high performance car for an extended period on low octane fuel.

I think the difference between 97 and 98 isn't too great, however most people I know who run high performance cars use V power and momentum, perhaps because they have the highest octane rating.
Almost all gasoline engines today, not just 'high perfrormance' have knock sensors and the ability to retard the ignition timing in response to knock. Using 95 RON in an engine calibrated for say 97 RON is not a particularly smart way of running the engine.

a) Relying on a 50 pence sensor to protect a Ł5k engine to save a couple of quid at the pump is a bit of flawed logic to me.

b) Running with retarded ignition timing reduces engine efficiency resulting in higher fuel consumption (less miles per gallon) and less power and acceleration. So the saving made at the pump is lost in any case.

Some engines actually benefit from higher octane than they were calibrated for, certainly worth trying a tank or two of 'the good stuff' before discounting the potential benefits. This is not easy to explain, so I'll not try.

Finally some premium fuels have more cleaning additives than others. I prefer clean inlet valves and injectors to dirty ones...
GeeJay is offline  
#11 Old 02-12-2013
Registered Users
 
Join Date: Jun 2011
Location: Ontario
Vehicle: 2012 Slk55 AMG black/black
Posts: 33
Country:
Chats: 0
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks: 17
Thanked 2 Times in 2 Posts
ron number to octane number

just a little info.

Some foreign vehicle manuals recommend a Research Octane Number (RON) instead of the more common octane rating that appears on most gasoline pumps. As a rule, the recommended octane rating can be determined by subtracting four (4) from the recommended RON number. A vehicle that calls for "91 RON" should use 87 octane gasoline (as measured by the (R + M) / 2 method). Using a higher grade than is required will not usually increase performance. However, if the vehicle is equipped with knock sensors, as many late model vehicles are, a higher octane grade may enhance performance.

woot i like that last sentence
Flatb3d is offline  
#12 Old 02-12-2013
Banned
 
Join Date: Mar 2011
Posts: 7,812
Country:
Chats: 0
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks: 681
Thanked 961 Times in 704 Posts
may enhance performance.

woot i like that last sentence[/QUOTE]

Does that work if you drink it
Flatb3d likes this.
JonB is offline  
#13 Old 02-12-2013
Registered Users
 
GeeJay's Avatar
 
Join Date: Jan 2009
Location: North-West Blighty.....
Vehicle: '16 C250d AMG Estate Premium+ Designo Hyacinth Metalic
Other Toys: Guitars... :-) Formerly '08 SLK200 6sp Palladium
Posts: 5,134
Country:
Chats: 91
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 70 Post(s)
Thanks: 652
Thanked 793 Times in 574 Posts
Quote:
Originally Posted by Flatb3d View Post
just a little info.

Some foreign vehicle manuals recommend a Research Octane Number (RON) instead of the more common octane rating that appears on most gasoline pumps. As a rule, the recommended octane rating can be determined by subtracting four (4) from the recommended RON number. A vehicle that calls for "91 RON" should use 87 octane gasoline (as measured by the (R + M) / 2 method). Using a higher grade than is required will not usually increase performance. However, if the vehicle is equipped with knock sensors, as many late model vehicles are, a higher octane grade may enhance performance.

woot i like that last sentence
As your in Canada and I'm in the UK, the SLK is a foreign car to both of us...

USA and Canada use (RON+MON)/2 to define the anti-knock index or AKI. The difference between RON (Research Octane Number), and MON (Motor Octane Number) can vary from blend to blend and is called sensitivity.


The AKI approach may be thought of as a better descriptor of octane quality, but it's by no means universal. Outside of the USA and Canada, I think the rest of the world uses RON as the headline figure at the pump.

In Europe, EN:228 proposes a minumum of 95 for RON and 85 for MON. So a sensitivity of 10 octane numbers might be expected, but real fuels can be different and still meet the regs. For example, sometimes the refinery has to 'give away' octane in order to comply with other properties defined in the specification.

If you fancy a more detailed read about octane, have a butchers at this:

http://www.crcao.com/reports/recents...l%20Report.pdf

As for 'knock sensor equipped engines may give more performance'. Strictly speaking, if the engine were perfectly calibrated there would be no benefit on running it on fuel with higher otctane quality than the calibration fuel. The knock sensor only provides a signal when the engine knocks on fuel that has insufficient octane quality to prevent knock.

In practice, some engine calibrations have some headroom and therefore the engine is able to benefit from higher octane fuel. This isn't due to the knock sensor.

Just trying to provide some clarification BTW.
GeeJay is offline  
#14 Old 02-13-2013
Registered Users
 
Join Date: Jun 2011
Location: Ontario
Vehicle: 2012 Slk55 AMG black/black
Posts: 33
Country:
Chats: 0
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks: 17
Thanked 2 Times in 2 Posts
Headroom

Thanks for the info. I wonder if our cars have any of that headroom ?
Heres hoping they do.
Flatb3d is offline  
#15 Old 02-15-2013
Guest
 
jameslk55x's Avatar
 
Join Date: Feb 2013
Location: VA
Vehicle: 2005 SLK55
Posts: 30
Country:
Chats: 0
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks: 7
Thanked 3 Times in 3 Posts
I go with V-Power here in the USA. If I was in your situation, I would still go with the V-Power.
jameslk55x is offline  
#16 Old 02-16-2013
Registered Users
 
Swagman's Avatar
 
Join Date: Oct 2010
Location: Northampton, UK
Vehicle: 12' SLK55 AMG
Other Toys: 15' HYUNDAI SANTA FE
Posts: 921
Country:
Chats: 0
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 36 Post(s)
Thanks: 77
Thanked 135 Times in 99 Posts
Garage
(Thread Starter)
Quote:
Originally Posted by jameslk55 View Post
I go with V-Power here in the USA. If I was in your situation, I would still go with the V-Power.
I did...

I finally got to fill her up yesterday (first time since I bought her), and she had V-Power goodness all the way...
Swagman is offline  
#17 Old 02-16-2013
Registered Users
 
Riverside Red's Avatar
 
Join Date: Dec 2012
Location: Darlington
Vehicle: SLK 55 AMG 2012MY
Other Toys: 2015 Solar Yellow Lotus Elise S, 2014 Audi S5 Sportback
Posts: 71
Country:
Chats: 0
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Thanks: 3
Thanked 2 Times in 2 Posts
Garage
My baby had a drink of V Power yesterday too, some strange looks in the petrol station as I had the roof down at 5:30pm in the dark!

RR
Flatb3d likes this.
Riverside Red is offline  
#18 Old 02-18-2013
Premium Member
 
ZeroZero's Avatar
 
Join Date: Sep 2009
Location: Coventry
Vehicle: 2005 SLK 55 AMG
Other Toys: Two Smart ForTwo(carbon footprint. offset)
Posts: 1,695
Country:
Chats: 0
Mentioned: 105 Post(s)
Tagged: 0 Thread(s)
Quoted: 257 Post(s)
Thanks: 15
Thanked 225 Times in 181 Posts
Hi All petrol heads

Well on to my 2rd tank of super unleaded 97 ron , I think there is a difference but as i drive a smart fortwo all week it may be just that , The wife keeps asking if im in sport mode LOL . I may try some V power 99 ron next fill up .


Cheers

Andy
ZeroZero is offline  
#19 Old 02-18-2013
Registered Users
 
GeeJay's Avatar
 
Join Date: Jan 2009
Location: North-West Blighty.....
Vehicle: '16 C250d AMG Estate Premium+ Designo Hyacinth Metalic
Other Toys: Guitars... :-) Formerly '08 SLK200 6sp Palladium
Posts: 5,134
Country:
Chats: 91
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 70 Post(s)
Thanks: 652
Thanked 793 Times in 574 Posts
Quote:
Originally Posted by ZeroZero View Post
Hi All petrol heads

I may try some V-Power 99 RON next fill up .


Cheers

Andy
Good call IMHO
GeeJay is offline  
#20 Old 02-19-2013
Registered Users
 
Riverside Red's Avatar
 
Join Date: Dec 2012
Location: Darlington
Vehicle: SLK 55 AMG 2012MY
Other Toys: 2015 Solar Yellow Lotus Elise S, 2014 Audi S5 Sportback
Posts: 71
Country:
Chats: 0
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Thanks: 3
Thanked 2 Times in 2 Posts
Garage
Try it in the Smart too, Brabus of course?



RR
Riverside Red is offline  
Sponsored Links
Advertisement
 
Reply

  Lower Navigation
Go Back   Mercedes Benz SLK Forum > General Discussion about Mercedes Benz SLKs > AMGs

Bookmarks

Quick Reply
Message:
Options
Upload your files to MEGAUPLOAD
Upload your images to ImageShack

Register Now



In order to be able to post messages on the Mercedes Benz SLK Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
SLK280 Fuel Filter question - Internal or External ? cx872 SLK R171 General Discussion 4 11-06-2012 08:35 AM
Fuel usage question mikiha SLK R170 General Discussion 20 04-29-2010 02:30 PM
New Member- fuel filler question rolltideslk General Discussion 5 01-09-2009 01:13 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome
 

Clubs, Garage Plus vBulletin Plugins by Drive Thru Online, Inc.