Ford V8

Irrelevant to my point about weight.

True, but the engine still produces 600 hp from a very neat 2 litres package.

Tim

Responsem?

Rubbish.

You mean e.g., not i.e.

Again, that should be e.g.

i.e. -> that is e.g. -> for example

Do you have a source for that?

I thought one of the reasons they've all gone for little turbos is that they are more efficient than a big NA on light loads. Which is most driving.

The turbo give you the output you need for the brochure's 0-60 figure. For most people that's enough.

And if the engine only lasts 60k miles? <shrugs>

Andy

hios damaged brain. Turbos are more fuel efficient when delivering comparable power

of course

RPM is an engine killer. Once you beef up the engine for turbo pressures, it doesn't need the revs and can be pretty long lived. As lw RPM diesel is.

See below.

But whether that engine could be used as a stand alone unit is the very real question. Unless you like comparing apples with oranges.

Just reading road tests of vaguely comparable vehicles. But very difficult to find a truly direct comparison.

The ads will claim that. But not tell you it is cheaper to produce.

As will a larger engine.

Quite. Like I said, cheap.

See your statement below.

If it doesn't need to rev it simply ain't going to produce the same BHP. Since BHP is a function of torque and RPM.

But being Turnip, you happily contradict yourself in the same post.

BTW, as I indicated, I'm referring only to petrol engines. But I'd guess you didn't understand that either.

Often max power occurs at less than max RPM. Unless your definition of 'peak' is itself defined as RPM at which max power occurs.

That simply isn't true. As a general rule the smaller the engine you are comparing a turbo may reduce overall mpg. On larger engine where induction losses dominate a turbo can increase economy. It really isn't safe to make such a blanket statement.

I will go further and ask if you can find any reference to a NA engine with a thermal efficiency of greater than 50%?

An engine where peak BHP coincided with maximum revs would be a rare beast.

Go on then. Give some real world figures.

And example of the same engine with turbo and without where the turbo unit gives better MPG at cruise.

Your goal posts have changed, your claim was, "petrol engines are never as good as a larger NA unit of the same output".

You're the one who made such a claim, and as usual have no evidence to back up this blanket statement.

Finally, a statement we can both agree on.

Is there any meaningful example of that situation?

Not sure what 'as good' means. Again, trying to find comparable isn't easy even if it's something as reasonably objective as mpg.

Unless you know what you're measuring, you can't make a comparison.

And since you are so certain I'm wrong you could do the research and find figures that prove it.

It may have escaped your notice, but turbos on petrol engines are nothing likes as common as on diesels. Indeed plenty makers of petrol cars have gone back from using turbos to simply fitting a bigger engine of similar output. Perhaps you'd explain just why - if they are such a panacea.

I?ve not studied the car market for a couple of years but last time I did, smaller, lighter, turbo units were the fashion. Which makers/models have gone back to bigger N/A?

Tim

The ones in dave's socialist utopia. Here if its not a hybrid, it probably has a turbo unless its REALLY top end, when it will be a supercharger.

Which is even more inefficient than a turbocharger.

I take it you know little of either, other than in your ancient 4x4 diesel?