Modern engine innovations

[BrickBat]

@Capn_Carl

Jim Wangers at Pontiac did more than just fine tuning to get better numbers in a magazine. On one occasion, a Firebird or GTO ran so fast, the magazine editors suspected foul play. They found that the “400” was actually a 428!

Yeah, Jim Wangers, Milt Schornack had a lot of cars given the full Royal Bobcat treatment, which was technically just a supertune, though it did involve minor parts changes like heavier advance weights and thinner head gaskets and adding poly-locks to the rocker arm studs. Great thing about a Pontiac was all the engines were the same external sizes. 400s could be swapped out for 428s, the 421’s were known to take the place of 389s, and I saw 0.30 over 455s residing where 326s used to.

[Machine_Elf]

@Ruken

Wikipedia tells me their Murai gets 400 mi / 650 km on 5.65 kg* of hydrogen. Although it seems capacity and range are improving, and those numbers may not all be from the same model year. Assuming the same capacity, I don’t know what kind of hit you take on losing the hybrid battery.

Sure, but the Mirai is equipped with a fuel cell instead of an internal combustion engine. So the difference in range isn’t just the loss of the hybrid aspect - you also lose the efficient production of electrical energy by the fuel cell

[mixdenny]

I’m late to this thread but the TV series Engine Masters explores a bunch of topics, even urban myths. One show was devoted to the street theory that the best modern carburetors could produce more horsepower then fuel injection. Indeed they did, but only for a short range of rpm at max power. The engine guru attributed it to charge cooling.

Last night a show showed how a flared inlet made more power as opposed to just a plain inlet. Even for supercharged engines.

[Machine_Elf]

@Machine_Elf

Using hydrogen obviously means no carbon. Whether there’s no CO2 associated with operating this engine will depend on how the hydrogen fuel is produced, but you definitely won’t get any CO2, CO, raw hydrocarbon, or particulate matter out of the tail pipe. (Ok, maybe you’ll get a smidge just from crankcase oil that gets burned, but it won’t be much.)

It occurred to me last night that since there’s no engine-out CO or hydrocarbon emissions from an H2-fueled IC engine, the conventional 3-way catalytic converter (which reduces tailpipe-out HC, CO, and NOx) could be eliminated, and the requirement to run with a stoichiometric mixture (for best 3-way cat efficiency) could also be eliminated. This means you could run an H2 engine with lean mixtures, garnering better efficiency due to lower combustion temps (less heat lost to combustion chamber surfaces) while still producing no CO or HC emissions. To some extent, you could also gain efficiency by leaving the throttle open more (reducing throttling loses) and leaning the mixture. Instead of the 3-way cat, you’d need an SCR (selective catalytic reducer) and a tank of diesel exhaust fluid (DEF), same as what many late-model diesel engines use to reduce tailpipe-out NOx.

Now I’m curious to know more about the details of how Toyota operates their H2 engine …