Ask any Audi R8 V8 or RS4 owner about the issue of dirty inlet valves.
Premium fuels. Hidden benefit
- Thread starter Simon
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Equilibirum after 10k miles.
Then there is a question about performance, which I'll try to find.
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I can't find it. It may not have been this channel.
Either way, how comes Shell, BP etc. never show if combustion is actually affected. They focus on carbon build up and potential corrosion.
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But most cars will have carbon build up like observed above as most people don't use premium fuels like V Power.
We don't have an epidemic of cars having faults due to carbon buildup every 10k miles.
No one said faults. We are talking about making an engine run efficiently rather than losing power or mpg due to dirt.
I'm struggling to see what you are arguing about
I just thought I'd post some picture of engine internals to counter some
Of the hearsay of 'I use cuz fuel and feels better' . Not sure why you are trying to make out dirt has no impact of the operation of an engine ?
Using decent fuels keeps you engine like new inside (as shown in the picture). If you think this is normal then I guess you haven't looked at many engines
I'm struggling to see what you are arguing about
I just thought I'd post some picture of engine internals to counter some
Of the hearsay of 'I use cuz fuel and feels better' . Not sure why you are trying to make out dirt has no impact of the operation of an engine ?
Using decent fuels keeps you engine like new inside (as shown in the picture). If you think this is normal then I guess you haven't looked at many engines
But no one ever presents evidence that normal carbon build up which happens pretty much in all cars actually results in a problem.
Yes very poor fuel, faulty fuel injectors, ignition etc. will lead to excessive carbon being produced but that is the primary cause.
Is my car down on power or efficiency? I haven't used premium fuels in 15k miles.
Also is the V8 S4 above actually port injected? That would go some way in explaining the difference.
So you think most cars on the road are as clean as the second picture above? i.e. What is normal.
Yes it is port injected. You can see the injectors in the photo
You might be down a few percent yes. The point is the dirt is a gradual thing so no one notices any decline. You then need a few tanks to clean it up. Again this won't be instant so it's hard for drivers to notice this effect
The cleaning effect potentially has more of an effect on the driving experience than the instant octane effect which people are always looking for
You might be down a few percent yes. The point is the dirt is a gradual thing so no one notices any decline. You then need a few tanks to clean it up. Again this won't be instant so it's hard for drivers to notice this effect
The cleaning effect potentially has more of an effect on the driving experience than the instant octane effect which people are always looking for
I had just found the exact engine, indirect injection as you say.
https://en.wikipedia.org/wiki/List_of_Volkswagen_Group_petrol_engines#B6S4
So aren't we seeing a best case scenario here, where the fuel actually has any chance of cleaning, going back to my previous post (where I thought it was direct) where I was confused how it could actively clean.
The only benefit in direct injection I can see is it might prevent injectors from getting clogged?
I'll admit it might make port injected engines look nicer, but I would like to see empirical evidence that it is resulting in a material difference to the performance or reliability of a car, where no other fault exists.
Remember we are asking people to spend hundreds, if not thousands extra in the lifetime of a car with average mileage.
https://en.wikipedia.org/wiki/List_of_Volkswagen_Group_petrol_engines#B6S4
So aren't we seeing a best case scenario here, where the fuel actually has any chance of cleaning, going back to my previous post (where I thought it was direct) where I was confused how it could actively clean.
The only benefit in direct injection I can see is it might prevent injectors from getting clogged?
I'll admit it might make port injected engines look nicer, but I would like to see empirical evidence that it is resulting in a material difference to the performance or reliability of a car, where no other fault exists.
Remember we are asking people to spend hundreds, if not thousands extra in the lifetime of a car with average mileage.
Soldato
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I thought it was pretty common knowledge that premium fuels generally result in enough of an increase in MPG to make them worthwhile?
If they keep the engine cleaner too, why the hell not.
If they keep the engine cleaner too, why the hell not.
It won't result in higher MPG just like that. If you notice anything in the short term, it is a placebo effect.
Shell/BP claim that in the long term, since your engine is cleaner it will supposedly result in better MPG.
And how many cars are we talking about here, that don't already ask owners to put in higher octane fuel?
Yes my response was a blanket statement. But I bet you werent going to respond to a post suggesting these fuels result in higher mpg.
Soldato
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I'm currently running an experiment with my 2.5 Mazda 6 (dullard that I am) but so far my spreadsheet suggests that it isn't a placebo effect.
So far as I know, they never designed it for higher octane like the RX-8s engine either.
Most "modern" cars (as in last 15 years or so) that are designed for different export markets will adapt to different octane fuel, it's not so much a "boost" but just not downgrading performance or efficiency. Even my crappy Zafira with the 1.6 Ecotec engine runs quieter and more efficiently on super unleaded (on the couple of occasions when nothing else was available), despite no mention of its use on the filler car or in the owners manual.
If your engine can benefit from higher octane then you will get better mpg
Clearly not:
Depends on the engine - may just provide "more" performance rather than "more" efficiency
Interesting... I'm going to make the swap to V-Power/Ultimate for the rest of the year to see how things go. I do very little mileage so the cost difference will be negligible. My engine is too old to see any performance benefit unless I tweak the ignition timing myself which I don't really fancy doing!
I noted improvements when I ran my Alfa on premium vs none premium. Also.sounded better and felt a lot.smoother.
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