Diesel is the same as heating oil. We used heating oil to run the boiler to heat a factory at which I was the maintenance engineer. One of my fitters ran his van on it for years.
If it is not used for road vehicles it won't be wasted.

Petroleum is nothing more than chains of hydrogen and carbon in various lengths. We know how to break these chains up, and to reform the pieces back together to get the products we want. At best, the straight gasoline fraction is 20%, and it is only 40 to 60 octane. We are already breaking up a lot of the heavier fractions to meet the gasoline demand.

So it is possible to turn diesel into gasoline. It just takes energy. There is just more profit in shipping excess diesel here to Europe, and importing their extra gasoline.

Existing refineries might need to be modified if we needed them to make the diesel into something else.
Most likely it will go to trucks, trains, ships, and jets.

I don't know on what basis you form your opinions, but readily available information (like this link https://www.eia.gov/Energyexplained/...e=oil_refining) indicates that a 42 gallon drum of crude oil yields about 19 to 20 gallons of gasoline (petrol). This is about 45% of the crude oil's original volume, or more than double your stated figure. Readily available information contradicts your opinions.

I said the straight gasoline fraction, by which I meant the portion of crude that is gasoline when it comes out of the ground, and can be recovered by simple distillation. It is known as straight run gasoline, and is mostly naphtha. The exact amount depends on the petroleum source; it can be as high as 40%, but can be under 20%. It hasn't been enough to meet demand since 1912. Over half of a barrel of crude becomes gasoline.

To get the gasoline needed for market, and to get it up to the proper octane, other fractions of the crude are cracked and reformed. This isn't alchemy, just chemistry, and is similar to the process in which we get hydrogen from natural gas.

https://www.afpm.org/the-refinery-process/
https://inside.mines.edu/~jjechura/R...&_Products.pdf page 11
https://en.wikipedia.org/wiki/Gasoline

Had an opportunity to experiment the other day on some long flat stretches of road in England. Using cruise control, I set it at various speeds and switched the screen to the instantaneous MPG reading. At 50 MPH I get a constant 57 MPG, but if I increase my speed to 80 MPH, my MPG only drops to 47. It seems like a small penalty of 10 MPG for such a large increase in speed. Thoughts?

It is a 17.5% drop in fuel efficiency. That's a huge drop.

When you put in percentage terms it sounds alot, but 10 MPG doesn't sound much. It might be 17.5% drop, but I've increased my speed by 60%. I rarely get a chance to use motorways so I'm uncertain what's considered normal and not.

At 50 you can enjoy the drive and scenery. At 80 you can enjoy driving but not the drive and scenery as you must totally focus on driving at that speed. I usually run 60-62 max no matter what the limit is so I can enjoy the drive.

Ten mpg may seem small in that context and perhaps it is. It's all context. Before I retired I removed the visor from my Kenworth. It went up from 8.2 to 8.5 mpg. Airtabs gained another .4 and different mudflaps another .25 mpg. It seems like nothing much but over 90k miles annually it's a lot.

Which is why MPG or km/L are poor units for fuel economy; they down play the efficiency increase or decrease to the viewer. They also require more math for calculating the average.

17.5% of my petrol bill for last year is £150. That is a huge amount to an OAP, so I curb my right foot, much though I enjoy driving fast.

This is one of the reasons I prefer looking at fuel burn, expressed in L/100 km, as opposed to MPG, when making comparisons. So if we use your numbers:

1) 50 MPH: 57 MPG (Imp?) = 4.96 L/100 km
2) 80 MPH: 47 MPG (Imp?) = 6.01 L/100 km

So for each mile you travel at the higher speed, you burn over 21% more fuel. Only you can determine if that's "worth it" to you. This comes down to "I'm okay burning 21% more fuel because I like going faster" or "I'm okay burning 21% more fuel because I like getting there sooner." Both are subjective measures, and that's okay.

On the other hand, if you want to make an objective comparison that also considers the trip's time (e.g., say you're a courier, and your employer pays you by the minute and he pays for fuel), then you need to assign a value to your time, and factor that into the fuel equation to come up with a "dollars per trip" comparison. In essence, at the higher speed, there would be a reduction in the salary paid to you due to the shorter trip time, and that would be offset by an increased fuel cost. Depending on how much you get paid per minute, that might be "worth it" to your employer, or not.

To be honest, long cross country trips like this are rare for me, so getting there sooner takes priority over what is essentially a few ££££ worth of fuel. Besides, my brother drove the 130 miles there as I had a heavy night drinking before, and he is paying me for the privilege of using my car, so either way, it matters very little.

No doubt about it. If you have to get someplace quickly then the extra petrol doesn't come into it. I used to drive from Fife to Greenock for work. 80 mile each way. Going into work I'd take my time and listen to the music. On the way home it was as fast as I could safely manage. I have even managed the Kingston Bridge (Glasgow) via M8 to Forth Road Bridge, in 35 minutes (around midnight). There was huge stretches where a pull would have meant a definite ban!

So there you have your answer, and good for you! :) I love hypermiling in my Q5 diesel SUV, just to see what efficiencies I can muster. I'll be doing a 1550 mile (each way) road trip in a couple weeks, so I'll be curious if I can do it in just two tanks, door to door. I see that as fun. Others? Not so much.

I also crave a Porsche 911 Turbo, which not only gets much worse cruising fuel economy, but also demands the most expensive premium fuel, AND it has this mystical influence that makes me want to drive in a much more spirited manner. Go figure! Net result will likely be 2x or 3x (or more?) cost per mile... and a load of excitement and fun and sexiness.

To each their own, as I like to say :)

I am hoping to drive through Germany one day, go to the Nurburgring etc. I would love to do an economy test at my cars top speed on the Autobahns at 155 Mph (limited). I'm guessing it would be single digits!

My most memorable experience on the Autobahn was when I was 15 or so, my Ma and I were visiting her family in Austria. We set our for the Munich airport in a rented Rover 75. She decided to try the fast lane, and gunned it. Mere seconds later some bright yellow VW (not sure which model, maybe a Lupo? Something I'd never seen stateside...) was right on us, flashing high beams. Oops.

Just dropping by to say hi to all.

Guys I'm getting a horrendous metal on metal scrapping noise at low speed and when I brake. Now, I'm thinking I may have eaten through my front pads already, and I don't think there's a low pad warning mech. They are huge brakes, 15" and barely have a lip yet, and they are twin piston calipers. Is it normal with performance brakes to eat through pads this quick? (13500 miles) and is it OK just to fit new pads without changing the barely worn discs?

How quickly brake pads wear out depends on how hard you use them and not on mileage (an F1 car will wear them out during one race of about 200 miles). Driving spiritedly, on winding roads will use brakes pretty quickly.
If discs are not worn there should be no need to replace them.

You can check your brakes fairly easy after you remove your wheel. With a flashlight you can check the disc and the pads to see if there is anything unusual. The noise could also come from a worn out hub bearing, when you brake it makes a noise and sometimes vibrates; I had that before thinking it was a brake issue. I had to replace the hub bearings every 30k miles on the Pontiac Sunfire I had, but those were low quality cars anyways and it was expected in an area full of pot holes.

Yep. I've heard that sound, too, Paul. Was the brake pads.

A mechanic will want to turn your discs, but that'll just wear them thinner and suck $$$ outta your wallet.

Replace with metallic brake pads, which are like normal pads but are embedded with tiny metal particles. These will will eventually smooth any scoring to the discs.

Normally, when brake pads get too worn there will be a warning sound BEFORE you score the discs. Perhaps you've been playing your music too loud, Paul!

Are you handy? Have you replaced pads? It's REALLY easy! It's a financial crime to pay someone to do it, because it's THAT simple.

Speaking of driving as fast as you can go...

Years ago, I took the '89 Civic on a road trip to visit my grandmother's birthplace and childhood town, Philipsburg, Montana.

At that time, Montana had NO freeway speed limits.

The 70hp Civic was pack with camping gear and the weight of me and a buddy.

Pedal to the floor, the little Honda could only go 85mph! (shrug)

Thanks for the help/answers. Had a wheel off today, pads are very low, and one has worn a bit wonky so perhaps one piston is a bit sticky. Lots of dry brake dust in there, so I'm going to get my mate to order some new pads and clean the calipers and discs up whilst he's there. Annoyingly the wheel where the most noise is coming from was bonded on the hub and I didn't have a rubber mallet to loosen it, but below is the drivers side disc.

That uneven wear between the two pads is suspicious.

Check this out, Paul...

https://www.google.com/search?q=one+...hrome&ie=UTF-8

Thanks Doug, although it may be just the dodgey angle of the photo causing a slight shadow.

There is always a slight angle to the wear of brake pads and shoes. This is the "servo effect" (nothing to do with the brake servo), whereby the leading edge of the pad/shoe is pulled in tighter than the trailing edge (leading edge being first part of the pad/shoe that any point of the disc/drum contacts). This was why, back in the days of drum front brakes, you used two leading shoes.
https://en.wikipedia.org/wiki/Twin-l...hoe_drum_brake
This is much less of an effect on the pads of a disc brake system, but it is measurable as a slight angle to the wear.

Turns out it's just my pads worn out luckily. But get this, the genuine Alcon pads are....sit down, take a breath, £271 or $358 USD JUST FOR THE PADS!!! So I've asked my friend to order Mintex ones at £65 a set. Crazy prices for original parts.

Pure gold flecks really improve your braking performance.