I was just curious, if anyone knows the answer; what is the maximum horsepower that can be extracted from a 2.0 liter 4 cylinder naturally aspirated gasoline engine? Say redline is around 7K RPM.

I’d be amazed if one could get 500 hp out of a non-turbo/supercharged 2.0 l with a 7000 rpm rev limit. HP = torque X RPM, you need to rev to get crazy hp.

2.0 liter 4 cylinder naturally aspirated gasoline engine and a redline around 7K RPM. The answer is not very much. The redline at 7K is for a V8, an inline 4 can rev way beyond 7K. In a racing version even a naturally aspirated inline 4 could run up to 15K and would likely be running 11-12K in no…

With or without N2O? To find out, figure the total volume that will be drawn in at 7K, calculate the total amount of gas that’ll be in the volume based on a theoretically perfect ratio, and figure the total energy contect of that gas. That gives you the true theoretical maximum power, as it assumes…

It seem 100HP per liter can be extracted with reasonable reliablity. This figure keeps going up as engine refinements and better materials are developed. The upper limits are much higher, but at the expense of reliability engine life and cost. My 1948 Chevy “stovebolt 6” developed only 85 HP from 2…

@Docnick And that was a hot engine. Wow! Soon, as Ford and others are proving, until electric power in the drive motor is the norm, small turbos in daily driving is preferred…torque is where it’s at. Getting lots of hp out of a small motor is vanity for the rich…or power hand tool and ouboard motor…

Stroke and connecting rod length seem to be the most limiting factors in RPMs.

Years ago, Toyota had an engine called the Formula Atlantic, it was racing only. It started with a 1.6 liter 4AGE engine and with about $30,000 worth of parts, plus precision machining and meticulous assembly, it would produce 320 HP at well over 7k rpm though.

I’d add “reciprocating masses”. A longer rod length weighs more as well as changing the angles at which it pushes the crank. A heavier piston is another drain on HP and on RPM ability. All other things equal, the lighter the reciprocating masses are is the more HP ends up in the crankshaft and the …

Latest I’ve heard is electronically activated valves. But it must be difficult to come up with something that’s better all-around than the ancient cam/valve setup…

Maximum Horsepower

General Discussion

shadowfax January 26, 2013, 2:04am 18

Wasn’t Mercedes fooling with that a few years ago? I remember it was supposed to go in a C-class, but I don’t think it ever did.

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Maximum Horsepower

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