Joga
A2OC Donor
The old SAABS were manual and had a (truly mechanical) freewheel though. A one-way coupler sort of.
Edit: just reflecting on @PlasticMac s post..
Edit: just reflecting on @PlasticMac s post..
Freewheeling vs foot off throttle
- Thread starter Welshboy
- Start date
steve_c
Grumpy OAP & A2OC Donor
Not just SAAB either, here in the UK Rovers used to come with a mechanical freewheel as routine.
Most cars with 2-stroke engines required a mechanical freewheel to protect the engine from wear when braking or coasting.
BearMcPear
Member
Engine friction increases more or less exponentially with RPM. It's a bit complicated if you have constant valve timing/deflection, as then max efficiency can be at different RPM due to valve train design like with my 4-cyl 600 cc Honda motorcycle (5000 RPM or so).
BearMcPear
Member
Also funnily enough when I was at Porsche the cars also had the option of free wheeling to conserve petrol in a 500 hp V8 
I use freewheeling in all my cars. My Octavia with DSG gearbox has it, but it does freewheel only in Eco driving mode. I would go nuts, if it would be freewheeling also in Normal, which some newer VAG cars do from factory (but this is solveable 
). Especially in city driving I find this function very annoying because I always look the traffic ahead and use engine braking whenever possible. But on highway I like it very much.
With manual cars I was freewheeling all the time by putting the transmission into neutral. Not once had a problem to select the proper gear back.
On Auris Hybrid is a little bit more complex to freewheel because you need to hold the throttle on precise one point, but this is annoying only on highway, since under 75km/h you can drive only on electric motor. The 4th hybrid generation has this limit raised to 110km/h (if I remmember correctly) and this would be perfect for me.
). Especially in city driving I find this function very annoying because I always look the traffic ahead and use engine braking whenever possible. But on highway I like it very much.With manual cars I was freewheeling all the time by putting the transmission into neutral. Not once had a problem to select the proper gear back.
On Auris Hybrid is a little bit more complex to freewheel because you need to hold the throttle on precise one point, but this is annoying only on highway, since under 75km/h you can drive only on electric motor. The 4th hybrid generation has this limit raised to 110km/h (if I remmember correctly) and this would be perfect for me.
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All this stuff (together with start/stop systems) is there only because of one reason: to lower CO2 emissions on test cycles and thus get as low as possible the average CO2 nr. for the whole fleet. This must be currently at 95g and for every gram over there are huge fines to be paid.Also funnily enough when I was at Porsche the cars also had the option of free wheeling to conserve petrol in a 500 hp V8
And due to this, the new ICE cars are slowly getting to the ''appliance'' status and basically losing the battle with electric cars. And we have already lost quite a few cars due to this (for example Suzuki Jimny) and many more will be lost in the next few years.
Considering i manage 93g with 1.2TDI and Spritmonitor data places Teslas into similar place, i'd wonder how they manage that.
Average for 1,2TDI is at 95g. So my only guess they all be driving 1,2-s there
. Or maybe they made spacial batch of WV XL1 for every company.Or maybe they think electricity comes from a wall socket and does not produce emissions...
Well, i am obviously joking, as were the "they" who wrote these regulations...
Yes, the regulations are totally pointless.
Thus you get into situation that the new Range Rover P440e plug in hybrid with its 2.7 tons and enormous petrol engine has between 18-21g of CO2 and is an environment friendly and super green car, while the tiny Honda Jazz is a really, really dirty car with its 82g of CO2
.
Thus you get into situation that the new Range Rover P440e plug in hybrid with its 2.7 tons and enormous petrol engine has between 18-21g of CO2 and is an environment friendly and super green car, while the tiny Honda Jazz is a really, really dirty car with its 82g of CO2
.
G
Guest 4123
Guest
The EU regulations regarding plug-in hybrids are about to change:Considering i manage 93g with 1.2TDI and Spritmonitor data places Teslas into similar place, i'd wonder how they manage that.
Average for 1,2TDI is at 95g. So my only guess they all be driving 1,2-s there
Or maybe they think electricity comes from a wall socket and does not produce emissions...
Well, i am obviously joking, as were the "they" who wrote these regulations...
No time to lose for the European Commission to make plug-in hybrid CO2 emission values more realistic — and no need to wait! - International Council on Clean Transportation
Assumptions regarding how frequently PHEVs are charged has a big impact on the gap between real-world and type-approval emissions.
theicct.org
EU to implement stricter hybrid vehicle regulations | electrive.com
www.electrive.com
Not before time!
RAB
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