Concept power units from 2030

[mzso]

So it could be compact and low vibration.

a compact X4 wouldn't be close to 90 deg and so would vibrate eg more than any car (3 or more cylinder) engine

If the opposing pistons are symmetrical, why would it vibrate?

[ispano6]

Forget that. Two stroke with turbo instead..

How about hydrogen rotary? Might be a good R&D challenge that Aramco could get on board with, considering their focus on blue ammonia/hydrogen. Maybe have to look farther ahead to 2040...

[Tommy Cookers]

How about hydrogen rotary? Might be a good R&D challenge that Aramco could get on board with, considering their focus on blue ammonia/hydrogen. Maybe have to look farther ahead to 2040...

the rotary might seem to have excessive combustion chamber area but .....
gaseous fuels have a wider explosive range and so can be run much leaner but ....
you'd need a 2 stage compressor

[wuzak]

While on the the topic of smaller/lighter engines. I wonder why no-one ever mad an X-4, or X-8 engine. (For racing anyway)

https://images2.imgbox.com/29/8b/6WVOL7cJ_o.gif

CoG too high, inconvenient exhaust and inlet placement.

Gearbox will be too high too.

In the current regulations, the crankshaft centreline is 90mm above the reference plane, and the CoG must be a minimum of 200mm above the reference plane.