Fuel Additives?

It's not the same fuel, but the learnings from racing make it into road cars.

Le Mans series, when running under diesel rules, was particularly important to the development of advanced diesel fuels.

You needed a highly tuned diesel engine with minimal emissions - something which traditionally was not a strong point for diesels. Power used to equal soot.

Redex. Upper cylinder lubricant. An original snake oil. ;-)

It's an interesting one. My last three cars recommend 97 octane petrol when you can get it.

But logging fuel consumption over a long journey says neither actually advanced the timing beyond that for 95.

Ah, I seem to recall the term 'upper cylinder lubricant' now you mention it, although from much later.

Certainly the car wasn't a performance model. I may be wrong but I suspect it may have had a side-valve engine, it was one of the box type Ford populars. My father replaced it with an Anglia, the rounded one, then a Cortina, the original model.

They don't make them like that any more. Fond memories of showing my housemate how to use a tourniquet to compress the spring when replacing a Macpherson strut.

You may need a tourniquet for and arm if it doesn't hold. I've only even compressed them with proper spring compressors- the last time on a Fiat Panda (the original one), so that was before 2001 when it was written off by a boy racer piling into it.

Quite - I'm so scared doing this I use two pairs of compressors. To be sure to be sure. ;-)

Spring compressors: luxury

Tourniquet is much safer than G-clamps.

Really? You'd need some strong string. ;-)

You wanna try Pug 205. They have 2 6mm holes in upper and lower perch. Get a length of 6mm!!!! threaded bar, cut to 2 equal lengths about 3" longer than extended shock. Put a nut and washer on each end and snug them up to the perch. Remove shock, unwind the nuts and swap spring.

It's a long time ago but at a guess I might have used nylon or polyester cord. These days I'd probably use my infinite supply of baler twine.

Mind you "proper" string was much stronger in those days.

Dave Plowman (News) used his keyboard to write :

I have never bought any but the cheapest supermarket fuel for my diesel and never had an issue with my car or company cars. My present diesel barely registers anything on the smoke test at MOT time. There is not even the slightest sign of soot at the rear, nor any smell at all from it.

I believe diesel injector cleaner additives have their uses, but only if there is a known problem. Rather than putting it in the tank, I would fill the filter with the cleaner, run the engine for a few seconds, then stop and leave it over night for the cleaner to work.

Brian Reay expressed precisely :

Redex!

It's a few years back, but a mate of mine always ran diesel golfs and at that time VW recommended and sold some sort of winter additive (anti-wax?) which he reckoned did prevent problems in cold snaps.

newshound formulated on Sunday :

The anti-waxing additive is added by the refineries now , in winter. There is no longer a need for owners to add it to the tank in winter. Besides, many diesels today (like mine) return hot unused diesel back to the tank, which helps prevent waxing on the move, in winter.

The diesel gets quite hot in passing through the high pressure pump. Any surplus diesel at the injectors then is diverted back to the fuel tank. Mine goes back via a thermostat, which diverts it via a small cooling radiator, to reduce the temperature if needed.

IIRC, the formula for diesel from the pumps changes according to season.

I suppose if you wanted to use summer diesel in winter an additive might help.

Both unleaded and diesel have a formulation change between seasons.

It requires some careful stock management on quieter stations, especially with the slower moving premium grades.

Indeed it does change, and I think has done so for many years. I guess there was something about those VWs that made them more sensitive? I didn't know about those clever systems described by Harry. (Don't suppose I will ever buy another diesel car, though).