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Premium diesel? Additives? Neither?

Discussion in 'off topic' started by Neil P, Aug 13, 2022.

  1. Martyn Miles

    Martyn Miles pfm Member

    Well, whatever is right or wrong, many lorries drive badly on motorways whatever their speed is limited at.
    Along with the high performance BMWs and the like.
    If I can avoid motorways I do.

    Call me an old duffer if you like, but the standard of driving has deteriorated markedly over the years.
    If I am sticking to a speed limit, why do many cars drive up close behind me and flash their
    To slow down ?
    No, to go faster.
  2. Sue Pertwee-Tyr

    Sue Pertwee-Tyr neither here nor there

    I'm not calling you an old duffer, and I tend to agree that the standard of driving has deteriorated, but motorways are still statistically the safest roads, which does suggest that speed alone is not the most important factor in road safety.
  3. Tony Lockhart

    Tony Lockhart Avoiding Stress, at Every Opportunity

    Make your mind up. Are you being overtaken by lorries or not?

    The roads are busier than they ever have been, so standards in the absence of traffic police will then deteriorate.
  4. Rcook

    Rcook pfm Member

    Super unleaded (E5, 97, 98, and 99 octane) petrol gives much better MPG and performance than the E10 fuels IME. I know several people who where E10 has caused problems - in a Kia Picanto and Vauxhall Adam it caused the MAF sensor to fail (not sure how that would do it, but it did as confirmed by main dealers in both cases)
  5. Ali T

    Ali T pfm Member

    I recall an episode where they bought a secondhand car and dyno’d it before and after using an additive. It did increase max output.
  6. clivem2

    clivem2 pfm Member

    Re BMWs and in earlier posts Audis being called out for motorway speeding and bad driving; drivers of all other makes of cars and vans are culprits too. Often it's the less powerful vehicles that are a pain as their drivers don't like to slow down because it's more of an effort to get up to high speed again.

    As for trucks overtaking with minuscule speed differentials - this is something that used to happen a great deal in the 70s and 80s but then less so until recently. I've noticed it happening more often since the price of fuel has escalated, I'm putting this behaviour down to truckers wanting to save fuel by maintaining a constant speed.
  7. AnilS

    AnilS pfm Member

    Sadly no it didn't. Check YouTube. They tested octane boosters and ALL reduced performance by 2%.

    I have a friend who still works in the oil industry and he carries out daily test analysis of the fuel they produce. When he tested additives, they either showed no change or a reduction in performance.

    The only thing he found, after an injector cleaner was added constantly on his test rig (not a dose into the tank as we would do), it had a slight improvement in cleaner emissions but when removed, it returned quickly to the previous levels.
    Snufkin likes this.
  8. Martyn Miles

    Martyn Miles pfm Member

    Yes, I am being overtaken by lorries.
    They are incredibly close, a few feet away from me, for what can be 5 minutes.
    Then they eventually pull out.
    The actual speed isn’t the issue.
    It’s the bad driving.
    Having incredibly heavy vehicles that close is very dangerous.
    I feel sure the lorry drivers know how dangerous it is.
  9. Tony Lockhart

    Tony Lockhart Avoiding Stress, at Every Opportunity

    So you’re travelling at under 60mph on a motorway. Well under. 55? In my opinion you’re creating this situation yourself.

    Reminds me of the guy at work whose brakes (discs and pads) lasted 158,000 miles because he barely touched them. Saved loads of money that way, and doing 55-58mph on the A14 twice a day.
    Reason he sold the car? The gearbox was screwed by always being used to slow the car down.

    I’d rather do 70-75mph when possible on a motorway and not be stressed out by being hemmed in by 48 tonners trying to make decent progress at their limited 56mph.
    Sue Pertwee-Tyr likes this.
  10. Sue Pertwee-Tyr

    Sue Pertwee-Tyr neither here nor there

    Don't forget that the lorry driver is looking ahead of you, and will probably become aware of a developing situation before you do, just because of his elevated sightline. That's not to excuse driving too close, but the risk isn't quite the same as it might be for a car doing it. Also, lorries are pretty big, and rear view mirrors do distort, it's possible it's not quite as close as you assume. But even if it is, the root cause of the problem is you. You complain about lorries in the middle lane taking an age to overtake, and you complain about lorries sitting behind you. If you cruise on the motorway at a speed which makes it difficult for lorries to overtake, this is a situation you put yourself in and the lorries seem damned either way.
  11. Martyn Miles

    Martyn Miles pfm Member

    So, I have on occasion, speeded up to 70 mph and then it’s the car/van tail-gaiters much to close behind me.
    Do they know the maximum speed limit.
    ( Speed limits are there for a reason...)
    Obviously they don’t care about the limit, as they just want to go as fast as possible.
    Not thought of fuel economy, or anything else.
    Like safe driving.
  12. Ali T

    Ali T pfm Member

    Oh yes it did. :)

    My memory was faulty though, it was Fifth Gear, and it was a Corrado, not a Golf-

    Tony Lockhart likes this.
  13. Sue Pertwee-Tyr

    Sue Pertwee-Tyr neither here nor there

    Speed limits are indeed there for a reason. But it's simplistic to think that safety is the primary consideration, especially on the motorway.
  14. AnilS

    AnilS pfm Member

    @Ali T

    My reference point

    Please do feedback if you have tried Redex and if you found a notable improvement in your car. I'd be interested to hear. Thanks.

    Performance fuels

  15. Ali T

    Ali T pfm Member

    Yes tried Redex before and no, haven’t noticed any (would you notice a 10hp difference in a 300+ hp car?) I have however with the Forte stuff, but only with the tankful I put it in to, but be that as it may, my priority is to keep my engine as clean as possible and to help reliability as much as possible long term, hence the 5k max oil change intervals and the use of Forte.

    Probably belt and braces though, a well maintained car would probably benefit just as much from a tankful of premium every 1000 miles or so.
    AnilS likes this.
  16. Martyn Miles

    Martyn Miles pfm Member

    So safely isn’t the prime consideration ?
    If you think that simplistic, then ask my sister-in-law ( a medical Doctor ) what the Police told
    her when she worked in Casualty.
  17. Sue Pertwee-Tyr

    Sue Pertwee-Tyr neither here nor there

    Does she post here? If not, perhaps you could precis?
  18. John Phillips

    John Phillips pfm Member

    I too thought HGVs were limited to under 60. However reality may be different.

    In the early hours of this morning (don't ask!) I was driving on the M25. Cruise control set at 73 MPH indicated (= 70 MPH actual on a GPS calibration when I last did that). I was barely overtaking the HGVs in lane 1. They were definitely not travelling at below 60 MPH. I observe that it is different during the day, though, when they do seem to keep below 60 (sometimes, frustratingly, in lanes 1,2 and 3 out of 4).

    On Diesel additives I do approve the extra-cost use of a diesel cleaner at each dealer service; I do occasionally buy a tank of V-Power D. or BP Ultimate D. I have occasionally tried Miller's diesel additive. I have no evidence of better performance or better fuel economy. For me it's a longevity bet.

    I think engine management systems today are adaptive for all of the emissions reasons, so I expect they get as much as possible out of whatever energy is actually in the fuel, as a side-effect.
  19. jimbob75

    jimbob75 pfm Member

    Safety is paramount, although impeding the progress of other traffic and forcing HGVs into the overtaking lanes poses more of a risk (certainly to other road users) than raising your speed slightly.

    Personally, I don't think there would be a significant adverse risk to safety if the motorway limits were raised (although I'd happily advocate a reduction to 20mph in heavily pedestrianised areas). The issue will always be cost (and of course political), since it would require improvement / re-alignment of the existing motorway curves, transitions, and superelevation, which are based upon a 70mph design speed (well, 120kph / 74.5mph actually)
  20. Tony Lockhart

    Tony Lockhart Avoiding Stress, at Every Opportunity

    The environmental issues with raising the U.K. speed limits will alway win. Fuel consumption at 80mph is noticeably higher than at 70.
    And it’s not just emissions from the exhaust that concern us. Tyre and brake debris come into the equation now.
    MUTTY1 likes this.

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