Vehicle & Technical > Defender
Sainsbury City Diesel MPG
DogVanMan:
Agreed, higher RON value for petrols = Higher performance, all other things being equal (and if the engine can use the higher octane)
Higher cetane rating for diesels has a similar effect, I think.. Question is, can pump diesel be any cetane rating by law?
G
Range Rover Blues:
The RON number is the octane, measured as the resistance to self-ignition so a waste of time putting higher RON in if you don't increase C:R or timing.
DogVanMan:
Yep, I understand that for petrol engines. For diesels, the cetane rating is similar to octane for petrol?
And specifically is it possible/likely that Sains City Diesel is lower cetane rating that other pump diesels? I'm sure it hasn't performed as well in MPG terms but I wonder if anyone else has had similar experience or can shed any light..?
G
Ridgeback:
Don't know about Sainsburys Diesel but I was getting very poor MPG from Tesco Diesel.
In my 200tdi you can only notice a small difference but in my BMW 530D it makes a huge difference. Load of flat spots and the MPG is way down.
530 miles to a tank with Tesco 600+ with Shell.
Range Rover Blues:
--- Quote from: DogVanMan on December 22, 2008, 16:45:11 ---Yep, I understand that for petrol engines. For diesels, the cetane rating is similar to octane for petrol?
And specifically is it possible/likely that Sains City Diesel is lower cetane rating that other pump diesels? I'm sure it hasn't performed as well in MPG terms but I wonder if anyone else has had similar experience or can shed any light..?
G
--- End quote ---
Cetane rating works the other way, but as few people have heard of it I didn't mention it. Now, somewhere at the back of my brain I think that a "reference" fuel is made up of Octane and Cetane :-k, 95 RON being equivelent to 95% ovtane, 5% cetane. Anyhoo, a high octane is obvioulsy a poor cetane and vice-versa. With Derv fuel we want them to self-ignite at combustion temperatures.
As for whether there is a standard for Cetane number I don't know.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version