Car gearboxes are a spectacular cause of power loss (in the order of 20% IIRC), so probably better to come up with a simple gear reduction or a belt-driven pulley system.
2:1 could easily mean crank the gearbox into a gear that approximately produces that ratio.
> You've tried to inject something on your own accord for possibly a misunderstanding??
WTH is that supposed to mean? If I misunderstood anything it was a honest mistake. GP suggested a RPM reduction for fuel efficiency reasons, it would be counterproductive to offset that efficiency gain with a high-loss mechanical device. There was neither ill intent nor hidden agenda.
Similarly -- the concerns about how to cool the device if it s putting down 100hp -- that's 74570 watts; it's unlikely they're using a harbor freight generator's alternator to generate that kind of power.
I didn't specify what type of gear box because there are many different options. Belts of the front pulleys would work. You could rig up a chain drive system as well. there are pros and cons to each.
Correct. IIRC again (numbers from 2010ish, probably there were some improvements since but I bet physics limit those) the best stick were 15%-20%; slushboxes were 25%-30%.
Such loss is justified by making the car able to operate on a much wider range, from standstill to highway speeds, and solve the ~zero torque at <1000rpm problem. IOW without a gearbox the car is useless.
Without that requirement a simple reduction would be much more efficient.
One of the huge benefits of going electric is that - in addition of having stellar electric to mechanical energy conversion efficiency (90-95%, vs a very lousy number I can't recall for chemical to mechanic energy) - the engine can basically be put on direct drive because torque is immediately available starting at 0rpm and all the way to max rpm, so no additional loss.
> I didn't specify what type of gear box because there are many different options. Belts of the front pulleys would work. You could rig up a chain drive system as well. there are pros and cons to each.
Totally fair! I didn't want to sound dismissing, only complementary.
a) expand the workable range of the IC engine (1000-5000rpm for Diesel, 1000-9000 - at best - for NA petrol, turbocharging dials it down)
b) solve the zero-to-low rpm problem that causes stalling due to nonexistent torque
It results in a complex device where many parts are still spinning even on the non-engaged gear. Look at a cut out of a manual transmission. The irony is that an epicyclic automatic transmission is mechanically efficient, up to the torque converter which uses fluid coupling.
Efficiency is a secondary goal to the ones above, without which the car would be useless.
I seem to recall improvements in that area around 2015 (probably driven by emissions regulations) but don't know the implementation details. One change was also a marked increase in available ratios (7, up to 10) which combined with better logic drives mpg down overall, sometimes lower than stick or dual clutch on standardised tests.