The Technical Questions Thread

[Ferrer]

Interesting. So despite the theoretical benefits, all show and no go as suspected.

Then, why do some manufacturers install those exhaust systems on four cylinder cars but then conceal them behind the bumpers? The engineers must have seen some kind of actual benefit for those won't they?

(Pictured current generation Honda Civic)

Also, I suppose that the actual benefits of a true dual exhaust vary whether there is one exhaust manifold (inline engines) or two exhaust manifolds (V or boxer engines).

[NSXType-R]

I think manufacturers are tucking away exhaust pipes now because it's not chic anymore to be spouting emissions. See, electric cars don't have exhaust pipes!

...never mind that electric cars still spout emissions, just somewhere else and not in the immediate area.

[NSXType-R]

Random question about new gearboxes- what happens if your battery dies and you need to enter neutral to push the car off the road?

For instance, my cousin just got a 2017 Honda Pilot and it has a gearbox that has a push button gearbox. So, how would you enter neutral with a dead battery?

[Rasmus]

Random question about new gearboxes- what happens if your battery dies and you need to enter neutral to push the car off the road?

For instance, my cousin just got a 2017 Honda Pilot and it has a gearbox that has a push button gearbox. So, how would you enter neutral with a dead battery?

Typically there's a mechanical, lockout lever hidden under an interior panel somewhere. Sometimes it can be difficult to find.

[NSXType-R]

Typically there's a mechanical, lockout lever hidden under an interior panel somewhere. Sometimes it can be difficult to find.

That's depressing to hear, and honestly to me that sounds like a safety liability. There's a margin of safety to be had with mechanical linkages, and as cool and forward as fly by wire is, you can't beat the mechanical precision and instantaneous feel of a real shift knob. Even airplanes have redundancy, and that's because it would really suck if you lost control of your rudder. There is no quick redundancy to this, and changing ergonomics for the sake of changing it is not a good idea. For instance, Jeep with their stupid gear lever design.

After Yelchin Death, Fiat Chrysler Fast-Tracks Jeep Gearshift Fix - NBC News

I can imagine an actual old school automatic shifter would have been really useful in those runaway Toyotas. It would have been fairly simple and fast to pop them into neutral and you'd still have control over the car.

[nissan pao]

Larger aircraft (generally greater than 1.5 tons) have dissipating wicks on trail edge surfaces. I have 2 questions myself and do not where to post them on this site. 1) where can I find the 2 shift levers and 2 linkage rods for a 1967 F100? The sites I have found only have the internal column parts and column handle. Where can I find consumable parts support for Keijidosha cars like the Nissan Pao? The site I intend to buy one from only offers hard parts. For example, this vehicle uses a Bosch N3 oil filter, which is not listed on Bosch's site.

[henk4]

Larger aircraft (generally greater than 1.5 tons) have dissipating wicks on trail edge surfaces. I have 2 questions myself and do not where to post them on this site. 1) where can I find the 2 shift levers and 2 linkage rods for a 1967 F100? The sites I have found only have the internal column parts and column handle. Where can I find consumable parts support for Keijidosha cars like the Nissan Pao? The site I intend to buy one from only offers hard parts. For example, this vehicle uses a Bosch N3 oil filter, which is not listed on Bosch's site.

I don't think you'll find a ready answer for your question on the Super Sabre here, but for the Pao, try your question here..

Nissan Forum | Nissan Forums - Index page

[wbcomposites]

I'm freshman here, wish to learn more from you guys. Thanks!

[NSXType-R]

Just curious, is there any advantage to compressed natural gas cars/trucks/busses? Is it because they burn cleaner/better on emissions?

A lot of taxis in Asia are compressed natural gas.

I always feel like they're such a pain in terms of packaging and refueling that it wasn't worth pursuing.

[f6fhellcat13]

As a very simple molecule - much simpler even than the idealized C₈H₁₈ and C₆H₆ of octane and benzene, respectively, that make up gasoline - you don't have to worry as much about unwanted polluting elements such as sulfur creeping into your fuel. See the prices of sweet vs. sour crude oil for another example of this playing out and their acceptability for refinement into diesel and gasoline. The sour stuff is diverted off into fuel oil (bunker fuel in maritime parlance, I believe) which can be burnt twelve nautical miles (or whatever international waters is) from anything approaching consequences...

Anyway, you get closer to the idealized hydrocarbon oxidation reaction and thus get far closer to only water and carbon dioxide in your exhaust. As a cyclist - being a cyclist is like being vegetarian: you have to tell everyone - the difference when I blow my nose after a commute behind diesel-burning and natural gas-burning buses is marked...

I'm sure your organic chemistry is much more finely-honed than mine; the nonsense chemistry they taught me as an aerospace engineer is pretty dim in the rearview mirror at this point. So you should probably be explaining this to me instead of the other way 'round.

EDIT: Also I think stoic is richer for CNG (the air fraction is smaller), so NO_X is less of an issue, but I'm not sure.

[NSXType-R]

As a very simple molecule - much simpler even than the idealized C₈H₁₈ and C₆H₆ of octane and benzene, respectively, that make up gasoline - you don't have to worry as much about unwanted polluting elements such as sulfur creeping into your fuel. See the prices of sweet vs. sour crude oil for another example of this playing out and their acceptability for refinement into diesel and gasoline. The sour stuff is diverted off into fuel oil (bunker fuel in maritime parlance, I believe) which can be burnt twelve nautical miles (or whatever international waters is) from anything approaching consequences...

Anyway, you get closer to the idealized hydrocarbon oxidation reaction and thus get far closer to only water and carbon dioxide in your exhaust. As a cyclist - being a cyclist is like being vegetarian: you have to tell everyone - the difference when I blow my nose after a commute behind diesel-burning and natural gas-burning buses is marked...

I'm sure your organic chemistry is much more finely-honed than mine; the nonsense chemistry they taught me as an aerospace engineer is pretty dim in the rearview mirror at this point. So you should probably be explaining this to me instead of the other way 'round.

EDIT: Also I think stoic is richer for CNG (the air fraction is smaller), so NO_X is less of an issue, but I'm not sure.

I think that's a reasonable answer. Thanks for saying that about organic chemistry, but it's been 6+ years since I've touched anything related to organic chemistry haha. I haven't thought about the stoichiometry for CNG, that may also be a factor too. Thanks again.