Driving at 30KPH causes engine damage and stalling

“lot of pressure on my engine” and that “cars were not built for that speed”

That's hilarious - have those people ever driven through a housing estate, supermarket car park, or attempted to ever park their vehicle?

Madness.

The engine damage talk sounds laughable but I reckon there's a hidden agenda, i.e the Governement / EU want people out of their cars for climate reasons. Slowly ramping the pain with lower speed limits and less parking is part of the mandate I suspect.

While comments that cars are not built for that speeds are completely ridiculous, this quote caught my attention:

It had also resulted in reduced noise and air pollution and lower carbon dioxide emissions.

Tyres might make less noise at 30 than 50 allright, but in many cars running on 2nd gear at 30 will actually generate more noise than running 50 in 3rd or even 4th.

When it comes to air pollution and carbon dioxie emission, I'm pretty sure that nearly every combustion engine car, will actually generate more pollution when running at 30km/h compared to 50km/h

Most economical speed for most car would be probably in range of 60-90 km/h. Anything lower than that will be less fuel economical, as well as anything more than that also will be less fuel economical.

And less fuel economy, meany more pollution and co2 emissions.

Do those idiots not realise there's a 30km/h limit in many urban areas - not just the PP?

The higher the engine revs, the more noise.

All depends on gear ratios.

Why can't there be a 40kph limit? Surely that's better than a drop of 40% below the 50kph limit.

In the US they dropped the "20 is plenty" campaign as it just wasn't working, but by introducing 25mph urban limits they found a 29% reduction in speed as it was seen as a good compromise.

Most noise you hear from a car is tyre noise.

"At low speeds, the engine and exhaust system are the primary sources of noise, but at about 35 mph tire noise comes into play. At freeway speeds, the tires account for about 60% of the noise a typical car makes"

I'm sitting on my couch in a city and I can hear cars, but what I can hear are tyres. Not a honda civic with a straight through exhaust.

At 50 kmh most of the noise you hear would be the tires, reducing the speed limit will remove the largest noise polluter. If you are interested in the topic I'd recommend this: https://www.youtube.com/watch?v=CTV-wwszGw8

(Don't how to delete duplicate links from a post in this stupid incarnation of a mobile site though)

I misread Cinios comment to read pollution rather than noise. That’s why I brought in the mean efficiency figure. Still, no need to require a source. You could easily find dB levels for tires and engines at certain speeds on average. Or next time your near a road, listen to the sound of a slow car and a fast car passing you by. On one, you will hear an engine and the other you will hear tire noise with few exceptions generally attributed to modded vehicles.

I'm pretty sure RPM is more important for fuel efficiency then speed. So proper use of your gears will mean a similar fuel efficiency at various speeds as you keep within the optimal range of RPM for your engine. I read somewhere that above 60 or 70kph drag, rolling resistance etc reduce you fuel efficiency outside of your RPM.

Same, the Tiguan managed it just fine last weekend, didn't seem to be under much strain at all lol.

Shouldn't be a problem for any car really but as said already, driving as 30kmph is incredibly boring on a big straight open road, much easier to do on smaller city streets / housing estates.

I'm wondering how strictly they will enforce it as Im sure adherence will be challenging for many. Its the same in Slane where only the rare driver adheres to it. Ironically it was introduced to counter against trucks losing control due to brake fade on the long steep decline and rolling over cars whereas in reality if you stuck to 30kmph you'd be at risk of being rolled over by these same trucks who in my experience completely ignore it.