New engine for fortwo?....

[Thrumbleux]

I wonder if this will find its way into the back of a fortwo...

http://www.autoblog.com/2014/12/12/renault-two-stroke-twincharged-diesel-engine/#image-1

[dervsmart]

Let's hope so

2 stroke diesels sound fantastic and have been around for eons in various forms, some had two crankshafts opposing each other with 2 pistons sharing a single cylinder.

For anyone wanting to hear them, look on youtube for 'detroit diesel'

[lalli_d1]

diesels are pointless on city cars/city driving which have DPF fitted. EU regulations state EVERY diesel needs one in order to conform to the EU emissions regulations

[Thrumbleux]

diesels are pointless on city cars/city driving which have DPF fitted. EU regulations state EVERY diesel needs one in order to conform to the EU emissions regulations

Biggest problem with DPFs is that they are fitted to large 3.0 litre cars which are used as city cars and run too cold as a consequence of being so far from their design point. A smaller engine working harder will be less troubled by DPF issues.
By doubling the amount of firing strokes, the two stroke need not run at the same extreme pressures to achieve the same power output as a four stroke. This alone alleviates (some) emission issues.

[lalli_d1]

if you say so mate... funny how the PSA 1.4, 1.6, 2.0, 2.2 and the 2.7 HDI is fitted with a DPF (i know they are 4 stroke and not 2)

also from what my bike mate tells me, 2 stroke is either being phased out or banned by the government (again i know thats for pertol)

[Thrumbleux]

if you say so mate... funny how the PSA 1.4, 1.6, 2.0, 2.2 and the 2.7 HDI is fitted with a DPF (i know they are 4 stroke and not 2)

I do say so... Go read up on NOx formation and see for yourself. DPFs are here to stay though. Particulate filters for GDI soon also.

also from what my bike mate tells me, 2 stroke is either being phased out or banned by the government (again i know thats for pertol)

Ancient history - all happened back in the 1980s. Diesel 2-strokes operate very differently from SI 2-strokes so UBHC isn't a problem for them.

[dervsmart]

if you say so mate... funny how the PSA 1.4, 1.6, 2.0, 2.2 and the 2.7 HDI is fitted with a DPF (i know they are 4 stroke and not 2)

also from what my bike mate tells me, 2 stroke is either being phased out or banned by the government (again i know thats for pertol)

2 stroke Diesels don't have oil injected with the fuel in the same manner a 2 stroke petrol does, the reason being it isn't required as diesel is oily enough (in laymans terms)

2 stroke petrol emissions weren't great with the 'then' current fuelling technology available to suit the price point of the vehicles (usually small motorcycles, so a carb and an oil pump) so they were legislated off the road in the 90's

Modern fuelling technology has progressed to a point now where it's pretty much efficient as it can be so the next step is to reduce sources of mechanical resistance within the engine itself (which is why you see more cam chains than belts these days, they're more efficient) - what better way to do that than ditch all the valve gear and go back to 2 stroke technology