E5 Fuel
- Thread starter Graham Hudson
- Start date
Maybe to add a bit extra information: Leaded fuel was only available short time before WW2 , mostly for aviation, less so for private customers. That is why owners of cast iron head vehicles will find a lot of wear on non-existant valve seats with unleaded from prewar times. Grinding in valves was a weekend joy the riders were used to.
Leaded fuel is not necessarily great for everybody´s engine as owners of prewar Tiger Moths with their Gipsy engines can tell. These engines had bronce heads , no seat inserts in them. So when leaded avgas was introduced widely in aviation in wartimes and later, these bronce heads had big troubles from seat wear due to lead content. The effect can be explained with soldering irons and copper tips: You will have noticed eroded copper tips from long use with tin solder containing lead. It eats away the copper , same with bronce valve seats. Now big trouble was with Tiger Moths after WW 2 , you only got avgas leaded that was bad for them . De Havilland specified for these engines unleaded but was not available untill recently from 1980 and later. Bad effect was now the different formula of unleaded that attacked rubber hoses or painted cork floats - so next bunch of problems.
Thanks for the Porsche photo, the engine is mainly Beetle type with alu heads and seat rings . I do not think you´d get wear on them from having unleaded fuel as the kind of alloyed cast iron seats should be fine with unleaded - same with all post war BMW bikes or other alu head engines. Engine speeds in the old Porsche are modest I guess, well below 5000rpm and valves not big, so unleaded quite allright I say.
Vic
Leaded fuel is not necessarily great for everybody´s engine as owners of prewar Tiger Moths with their Gipsy engines can tell. These engines had bronce heads , no seat inserts in them. So when leaded avgas was introduced widely in aviation in wartimes and later, these bronce heads had big troubles from seat wear due to lead content. The effect can be explained with soldering irons and copper tips: You will have noticed eroded copper tips from long use with tin solder containing lead. It eats away the copper , same with bronce valve seats. Now big trouble was with Tiger Moths after WW 2 , you only got avgas leaded that was bad for them . De Havilland specified for these engines unleaded but was not available untill recently from 1980 and later. Bad effect was now the different formula of unleaded that attacked rubber hoses or painted cork floats - so next bunch of problems.
Thanks for the Porsche photo, the engine is mainly Beetle type with alu heads and seat rings . I do not think you´d get wear on them from having unleaded fuel as the kind of alloyed cast iron seats should be fine with unleaded - same with all post war BMW bikes or other alu head engines. Engine speeds in the old Porsche are modest I guess, well below 5000rpm and valves not big, so unleaded quite allright I say.
Vic
Peter,
I agree with you 100%. I think they were/are snake oil. To actually do anything something about the little balls would have to change. When they first came out I remember people saying that they replaced the lead in leaded fuel. But tetraethyl lead is different from pure lead. I also remember that when unleaded fuel first came out the gas station people used to say the reason unleaded was more expensive was the refineries had to process the fuel to get the lead that they placed in the fuel out and that drove up the cost. My response was why would you place something the fuel you are just going to take out later. It was all non-sense.
There are testimonials all over the Internet claiming these fuel pellets improve mileage and power - more proof of how useless anecdotal evidence is, the placebo effect, confirmation bias and disinformation by snake oil sellers. The products are described as catalysts that "reformulate" the fuel, but the explanations are invariably pseudo-scientific gibberish.
To take only one obvious objection, if auto makers could improve their mandated Corporate Average Fuel Economy figures by tossing a few metal pellets into their fuel tanks, isn't it likely they'd do so?
To take only one obvious objection, if auto makers could improve their mandated Corporate Average Fuel Economy figures by tossing a few metal pellets into their fuel tanks, isn't it likely they'd do so?