Why not on of these 3 cyl engines

[Spyd_Piper]

If they wanted to, the 1330 could net 160hp. Naturally Aspirated. Or more reliably - adding a turbo setup (minimal weight gain) could net whatever power realistically wanted.

[Bob Denman]

Horsepower is rarely cheap... and never free!
Rotax builds a great engine, with a service life that is far in excess of 100,000 miles.

How many of those miles are you willing to trade, for the horsepower that you want?

[Spyd_Piper]

Horsepower doesn't hurt engine or reliability. Heat or high rpm does. Its all in the design and modifications of that.

Reliably issues only come into play at the extremes. Gaining power for any given engine design usually comes at an rpm increase for the power curve. Or creating heat that can't be dissipated. However, most engines become more reliable, run cooler, dissipate heat better with proper power / efficiency increase. 160hp is the extreme. 130hp is not.

[Bob Denman]

But horsepower does create heat; the cooling systems have to be able to handle the extra load...

[Spyd_Piper]

But horsepower does create heat; the cooling systems have to be able to handle the extra load...

No. Heat is lost energy that is not transferred. You will never overheat a really built engine at 1/2 to wot. Its always at idle or low speeds that these overheat.

I understand where you are coming from, but that is very old school. Back in the day of carburetors, big cams made the engine run like crap at low rpm. Very inefficient. Late valve closing and raw fuel would be in the exhaust. Where it could continue to burn. This would heat up the exhaust manifolds, engine and full exhaust system. Creating a ton of heat. And problems. Overheating was normal and you couldn't let the engine idle long or cruise long without cooling modifications etc.
Today and EFI is not like this at all. Huge cams can purr like a kitten. Fuel is not wasted or ever dumped in the exhaust. There is more problems fighting with heat when meeting emissions. But not like this on the performance side.