Premium Diesel

[gregozedobe]

BP Ultimate diesel is also higher cetane rating than some other brands (particularly the cheaper "no-name" stuff). Cetane is similar to Octane for petrol.

If (and it is a very big IF) the engine was designed and tuned to take advantage of the higher cetane, it would be possible get more power and/or better fuel economy from a higher cetane (but it may damage your engine if you put lower cetane diesel into it).

IIRC the gas-to-liquid (GTL) diesel gave pretty good results in some trials (but was too expensive to make on a commercial scale).

[vmq6695]

Well, I don't get it. Diesel engines don't work like petrol engines, the fuel is injected into the cylinder in the compression stroke. So, it either ignites or it doesn't. I can't see how an "utimate" diesel is going to ignite any easier, faster or cleaner to give you more "oomph".

BP claims that Ultimate Diesel has a cetane rating higher than average ULSD; BP claims Ultimate normally rates 55 - 60, and is always above 50.

That suggests that ignition events should be more optimal or, in your terms, easier, faster, and cleaner.

I've run a few tanks of Ultimate Diesel now. My TDI is continuing to improve in fuel economy, but I've not seen any especial change in the trend to better economy due to the Ultimate Diesel. But that's also to be expected from the theory: clean ULSD is less energy dense than old high sulfur diesel fuel.

I suspect idling is smoother with Ultimate Diesel, but I didn't do a rigorous measure of roughness before switching to Ultimate.

The price difference is tiny. And as cogdoc noted, once a BP station has its diesel tanks and pumps cleaned and renovated for Ultimate Diesel, it only retails Ultimate Diesel from then on.

Cheers

V

[Greg Roles]

Price difference of BP Ultimate diesel was 0.02 cents per litre to BP ULP ultimate, and 7 c per litre to normal ULP at BP yesterday. Certainly dropped down to stuff all!

[gregozedobe]

Was that because ULP increased ? (rather than Diesel decreasing)

There's been quite a bit of skulduggery going on with fuel prices in the last few weeks here in Canberra. Mobil was 20 odd cents a litre cheaper for all types of fuel c.f. Caltex and BP.

[dammfool]

I got a take full yesterday for my polo and noticed it smells alot more than normal diesel when filling up.Its seems when im giving it a boot full it doesnt blow as much soot.

[Gigitt]

For diesel higher cetane means nothing unless the fuel is dense.

This is the problem with Biodiesel. It has a higher cetane than dinodiesel, but is less dense - so you get the nice running engine and smooth power delivery from a slightly faster burning fuel - but because it is less dense you actually get less power.

You car ecu is designed to inject a volume of fuel - a less dense volume means less bang.

So You would hope that BP Ultimate is not pulling wool over you eyes by having the same name as petrol ultimate and tricking you into buying a more expensive fuel cause you think you will run more efficiently and get more power and km's out of you tank.

Personally if you buy it for the 'injection cleaning' portion - that makes for some pretty expensive injector cleaner!

You can buy Super Diesel Treatment in 250ml and 1lt. 1lt will cost you about $28 and treatment for a 55lt tank of diesel is about 15ml. So that means ~$0.42 per tank. And if you are paying 10c more /lt for an injection cleaner = $5.50!!!!

Even at $0.02 /lt differnece that means $1.10 per tank!

ouch!

You would hope that it gives you more bang power and not because your injectors are clean!

my 2c

[Mischa]

been using bp ultimate diesel for a few tanks now. if there is a difference, its too small to make a comment about

[Mister_duck]

How long has the bp ultimate diesel been available in sydney for Mischa ? Can't say I have noticed it yet, and I use bp 80% of the time

[Greg Roles]

If it's like Brisbane, it hits the bigger "city" BP's first, and filters down the line from there. Go out of town 50kms and you're stuck with the "old stuff", even at big servo's. Perhaps they have a strategic roll out or something.

I must say you get the poo's when you have to pull in somewhere unusual, and you pay about the same price for "the old stuff"...

[gldgti]

every time i put dinodiesel in my tank, the car seems to run worse.... i'll just stick with the less dense, less powerful biodiesel i reckon

[Preen59]

every time i put dinodiesel in my tank, the car seems to run worse.... i'll just stick with the less dense, less powerful biodiesel i reckon

Hahaha, "Dino Diesel".

My old man was saying Shell used to sell super diesel or something (can't remember the name) yeeeeeeears ago. He reckoned it was good stuff, and didn't even smell like normal diesel...

Is this stuff supposed to be better for your engine or what?

[Greg Roles]

Has a higher cetane apparently, and the usual "ultimate" cleaners etc, which will aid in keeping newer injectors clean at least. Certainly has a flash looking sticker on the nozzle!