Ford V8

Yes but these are all to do with volumetric efficiency (getting more fuel and air into the cylinder), including the periphery of 2 inlet valves being bigger than one large one.

Why should this increase thermal efficiency to give more miles per gallon if you might be happy with a modest performance and more mpg?

I can see the point about the mass of valve gear and losses in compressing the spring but surely you get most of that back as the spring pushes the cam load back round.

Capable certainly. Retired racing driver Eddie Pullen (and other co-drivers) conducted an endurance speed run for Ford in the Mojave desert in 1933 with a stock V8 Saloon. Covering over 33K miles in a month. That was an average speed over 40mph, and that included servicing, refuelling, and driver changes.

It certainly suffices to demonstrate your inability to communicate in any meaningful fashion...

Tim

It is amazing what a lot of information can be gleaned from usenet. Did you have this stuff lurking on your files or did you resort to doing what the firts correspondents urged? Either way I am grateful. Had you considered the average journey on any leg of the course was somthing like 10moh faster than the average daily commute anywhere on earth these days?

And that it took an highly motivated team of not specified attendants, and professional racing car drivers with a network of enviable logistics to accomplish this on a deserted highway?

And you have not supplied fuel consumption figures. Which raises the question of what the performance would do vis a vis the time taken with tyre changes and accidents as the cars deteriorated if they had introduced chicanes and what have you corners and hills?

It was, I presume, hardly the course of a vehicle testing station that would be set up to test fuel figures on average road journeys these days.

I would like to watch the video though. Got a link or failing that, what fuel and oils were they using and how were the bearings and linkages set up?

More a fluke of timing, I watched a video on the production of the original ford V8 a while ago:

It was an endurance speed attempt round a circuit, so not surprising.

From memory, it was about 19 mpg... presumably US gallons - so about 24 mpg to us.

I don't think fuel efficiency was much of a consideration in the US until the 1970's.

There are some clips of video of some of the various tests etc included in the one above.

There are also some web sites that have more detail, such as:

I am pretty sure this must be correct as the RR Kestrel was designed for that almost straight away.

The question then is: Why did they not build a diesel with all that Hi Tech going for them?

They would have got to Berlin immediately with diesel Gryphons, quite a lot of the way back as well probably.

"The output of the engine depends solely on the mass of air it can be made to consume efficiently" which would become in diesels a deciding factor of the war... if...

However Churchill surrounded himself with a Mediocracy, I can only presume as par for the course in his life, was intentional. With the inevitable design faults.

For a given definition of "meaningful" would you care to reconsider the meaning of the adjacent word: "fashion".

Does it? Valve bounce reduces all and speed is the whole point of no longer using donkeys when people could afford horses, so that as youth increases the ability to go faster the inevitability of the go fater stripe glows ever more ruddy.

Would the increased number of valves allow greater cooling efficiency or was it always about valve bounce?

I love watching you post ignorant drivel.

Why didn't they go straight to jet engines?

Because it's not that easy.?

neither.

Getting power out of a non blown engine is down to one thing. peak RPM.

I spent a happy couple of hours talking to Brian Hary who deigned F1 and Indycar engines. Without turbos, what limits performance is top RPM and what limits that is the ability to open and clse enough valve area - and

In essence you can only get so much compressions out of a petrol style engine, so you can only get so much band per stroke, so to get more power you need more bangs per second.

Ultimately once they found out how to get RpM up to 17-19000 in the Cosworth and post Cosworth ere, the problem became valve bounce, as even with massive springs and overhead cams the sheer force to operate it was sapping power, so pneumatic valves happened.

Turbos remove the need for higher RPM allowing what is effectively far higher compression ratios, and reducing the need for such big valves. And for such high RPM

None of this relates to fuel efficiency: That's is far greater these days because of electronic injection and mapping allowing an optimal fuel level and inlet pressure depending on the load and RPM. That and lower friction materials nets you a more efficient motor overall.

That fits my understanding.

So why have such complicated engines when these above things can be implemented on a simple OHV engine doing less than 5krpm and no variable valve timing?

because lower vehicle weight improves not engine fuel efficiency, but mpg.

VVT extends rpm range. Allows more power from a smaller lighter engine.

Because, like for like, BHP goes up with RPM.

Variable valve timing allows a much better torque curve. And the shape of that curve is what matters for day to day driving.

Multi valve engines also are better for emissions.

Just what tricks they get up to on an F1 engine when all it has to do is last once race of little relevance to a road car.

Turbos may be a nice cheap way of making an engine of a given output, but with petrol engines are never as good as a larger NA unit of the same output. Despite the marketing hype.

You?re ignoring the weight/volume penalty of a large N/A engine as opposed to a turbo engine. What weight engine would you need to replace a 600 hp 2 litre three cylinder engine?

More to the point, who would want a crude 3 cylinder engine in a decent road car anyway? And of course that vehicle is a hybrid. So you get the weight penalty from the electric motor and battery pack.

He is also ignoring frictional loses - larger in a big engine.

And you're ignoring that with a petrol engine a turbo unit of the same output as a larger NA one is generally more thirsty. It's just a cheap way of getting more power.

Speaking of grammar, your senttence didn't need a question mark.

Thicko!

In other news, 'sentence' only requires one 't'.