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The big engines of WWII ate dust for months between overhauls. Ask ANYONE who flew from, say, Malta or in North Africa. I have and they ran just fine for longer than anticipated.
I can't think of even ONE modern engine that could do it except maybe a diesel ... and they were NOT the engines of choice in WWII. The ONLY reason we are flirting with diesels in aviation today is the cost of fuel. If it weren't that, nobody would bother with them at all except in trucks hauling freight and large boats and ships. They are good for good torque at low RPM at one speed for a long time ... hardly an aviation need.
Greg Ive been thinking about this a little. In racing the engine just has to last to the end of the race the maximum power is therefor pretty much that. For an Aero engine it must last for the cycles you say and hold together. The maximum power is therefore not the maximum possible but the maximum certified to be used. Reading about engines there is frequently a remark somewhere that so and so engine produced 4,000 or 5,000HP on a test bed. They never say how long it held together and no one pretends it would be safe to run it in an AC at that power.If the modern guys scaled up, they might do better and might not ... they have forgotten a LOT of tribal knowledge about large piston engines because they aren't made and have't been made for 50+ years. Go look at an Allison V-1710 or a Merlin 1650 V-12. 4 valves per cylinder and made very close to 1 HP per cubic inch or 61.02 Hp per liter and better.
Yes there are modern engines out there that make that power level, but do they do it like an aviation engine? Like maybe 100% power for takeoff and climb (say 15 - 20 minutes) and then 60 - 75% power for another 5 - 8 hours, and do it every other day or so for 400+ hours, and do it efficiently at 25,000 feet? Maybe four at a time as in a 4-engine bomber? And continue to run with bullet holes in the crankcase? With maintenance out in the open on an airfield that was recently a farmer's field, complete with rain, dust, bugs, birds, and everything else?
I could throw a handful of sand into the intake of ANY Formula 1 car and it would expire in less than 10 minutes. The big engines of WWII ate dust for months between overhauls. Ask ANYONE who flew from, say, Malta or in North Africa. I have and they ran just fine for longer than anticipated.
In racing the engine just has to last to the end of the race the maximum power is therefor pretty much that. For an Aero engine it must last for the cycles you say and hold together. The maximum power is therefore not the maximum possible but the maximum certified to be used.
Let's put this into perspective.
Nobody has made a 150 - 2500 HP aero piston engine in about 70 years. The last ones that were liquied cooled displaced 1649 and 1710 cubic inches and made 1,850 - 2,200 HP reliably for 400+ hours between overhauls.
But those engines I listed were used in types, even if they weren't long-term production airframes.I'm SURE you KNOW that the Allison 3420 was just two 1710's ona common crankcase. They were V-1710-based.
They only made 538 Vultures and they were unsuccessful. I never considered them and they were abaondoned early in the war.
The AM-42 started out in life as the AM-34, designed in Italy, and morphed into the AM-35, then the AM-38 and, finally, the AM-42. It had some Soviet input in that time, naturally, but was a larger-displacement engine than the MNerlin or the Allison ... alrgely due to les sophisticated fuel used in development and operation. It had the very unique characteristic of having a longer stroke on one side than the other due to articulated connecting rods on one side!
My entire point is nobody has made large HP or large-displacement piston aero engines in a LONG time. So there has been a very large loss of knowledge about how to do it. What is your point? No argument, just curious as to what direction your comments are leading. I agree with them, but they don't address my contention and I was just wondering.
I had a GM 702.9 CID V-12 in my '68 Chevelle that was a real ass-kicker...
The 702 engine was about 1958 vintage and ran like a beast...plus it was a real head turner at the show and shines back in the 80's
Big cubes had their place in the sun at one time...
Can modern air cooled inline engines compete with the water cooled engines of WWII?
Perhaps there are no modern engines of those ratings being produced, if that is the case, then could modern air cooled technology produce engines competitive with water cooled engines of WWII?
Yep!They looked like 2 V-6's welded together because of the 2 rocker arm covers on each side, but it was actually one big cylinder block.