bwilson4web
Well-known member
Hi,
Apparently VW (and others) have been actively spreading a lot of false information about the Prius versus the TDI diesels. Sad to say, we've learned VW committed a fraud since at least 2009 and we are sorry for this. Diesels did not deserve this fraud nor their owners. But it also reveals the long standing efforts by professional liars to mislead about the Prius. This posting is an attempt to bring facts and data.
No, we are not interested in "capturing" TDI owners. Rather, we want to address the FUD (fear uncertainty doubt) that these professional liars have been spreading. If you prefer to spread NOx with a high performance TDI, go ahead just as VW wants you to do. As an owner of two Prius, I don't care.
ABOUT THE PRIUS
It is not a perfect car. The monocoque body has been too flexible since 2004. The 2004-09 Prius have after-market, body stiffener plates. This is not a car for precise steering.
It is also has average acceleration. The traction battery torque comes on instantly but after about 30 yards, the car fades. Now 30 yards is enough to beat the light into the best lane but others will reach the next light first. The Prius is not a street racer BUT fast enough to get the best lane.
ABOUT THE ENGINE
The power-stroke expansion ratio is 13:1, close but not in the diesel range. Yet this means it has higher energy extraction than any other gas-only car. This balances the NOx emissions while achieving excellent thermodynamic efficiency.
The Prius engine trick is leaving the intake valves open during part of the compression stroke pushing part of the charge back into the intake manifold for the next cylinder intake. This means the true compression is 8:1 allowing use of affordable, regular gas. Because part of the fuel-air charge is pushed back into the intake manifold, it is mixed better than any gas-only car. It also means the energy lost compressing the charge is less than a diesel, another energy saving.
In contrast, a diesel has a significant requirement for the starter and battery. Even then, some of the older diesels needed a pause in cold weather before driving to warm up the cylinders. In contrast, the Prius starts the engine in less than 200 ms. When warmed up, even faster.
ABOUT THE TRANSMISSION
Many do not understand that the traction battery is part of the transmission and not a separate drive system. This means the engine with this transmission will always match to the load. Best of all, there are no clutches . . . none.
There was a patent case ruled against Toyota but it was because micro-processors are used to manage the transmission operation. That patent has expired.
As for the traction battery, it is part of the transmission, the electronic shift mechanism. We have found perfectly working Prius with 1/3d of the traction battery capacity still running. Best of all, anyone who understands basic electronics can rebuild the traction battery and get a better car.
SUMMARY
If you decide to try the Prius, buy a used one with some warranty remaining. You might find it does not meet your expectations, so sell it. Understand the Prius is not for everyone. Try it and if you like it, more modern ones are available. But minimize your risk by starting with a used one.
Avoid the 2001-03 Prius unless you want to learn about hybrid technology as an applied engineering course. This is not for technically 'light-weights', only serious engineers need apply. We have one and are very happy with it but I'm an engineer.
The 2004-09 Prius is a fine functional car with a 1.5L engine. It is best for non-technical car drivers yet offers some interesting options for the skilled. The 2010-current Prius will soon be much more affordable and we have one too.
The 2016 Prius is not available until December/January. NEVER buy the first model year in a strange technology. Wait at least two year (like we will) and let the 'pioneers' work out the initial bugs.
Bob Wilson
Apparently VW (and others) have been actively spreading a lot of false information about the Prius versus the TDI diesels. Sad to say, we've learned VW committed a fraud since at least 2009 and we are sorry for this. Diesels did not deserve this fraud nor their owners. But it also reveals the long standing efforts by professional liars to mislead about the Prius. This posting is an attempt to bring facts and data.
No, we are not interested in "capturing" TDI owners. Rather, we want to address the FUD (fear uncertainty doubt) that these professional liars have been spreading. If you prefer to spread NOx with a high performance TDI, go ahead just as VW wants you to do. As an owner of two Prius, I don't care.
ABOUT THE PRIUS
It is not a perfect car. The monocoque body has been too flexible since 2004. The 2004-09 Prius have after-market, body stiffener plates. This is not a car for precise steering.
It is also has average acceleration. The traction battery torque comes on instantly but after about 30 yards, the car fades. Now 30 yards is enough to beat the light into the best lane but others will reach the next light first. The Prius is not a street racer BUT fast enough to get the best lane.
ABOUT THE ENGINE
The power-stroke expansion ratio is 13:1, close but not in the diesel range. Yet this means it has higher energy extraction than any other gas-only car. This balances the NOx emissions while achieving excellent thermodynamic efficiency.
The Prius engine trick is leaving the intake valves open during part of the compression stroke pushing part of the charge back into the intake manifold for the next cylinder intake. This means the true compression is 8:1 allowing use of affordable, regular gas. Because part of the fuel-air charge is pushed back into the intake manifold, it is mixed better than any gas-only car. It also means the energy lost compressing the charge is less than a diesel, another energy saving.
In contrast, a diesel has a significant requirement for the starter and battery. Even then, some of the older diesels needed a pause in cold weather before driving to warm up the cylinders. In contrast, the Prius starts the engine in less than 200 ms. When warmed up, even faster.
ABOUT THE TRANSMISSION
Many do not understand that the traction battery is part of the transmission and not a separate drive system. This means the engine with this transmission will always match to the load. Best of all, there are no clutches . . . none.
There was a patent case ruled against Toyota but it was because micro-processors are used to manage the transmission operation. That patent has expired.
As for the traction battery, it is part of the transmission, the electronic shift mechanism. We have found perfectly working Prius with 1/3d of the traction battery capacity still running. Best of all, anyone who understands basic electronics can rebuild the traction battery and get a better car.
SUMMARY
If you decide to try the Prius, buy a used one with some warranty remaining. You might find it does not meet your expectations, so sell it. Understand the Prius is not for everyone. Try it and if you like it, more modern ones are available. But minimize your risk by starting with a used one.
Avoid the 2001-03 Prius unless you want to learn about hybrid technology as an applied engineering course. This is not for technically 'light-weights', only serious engineers need apply. We have one and are very happy with it but I'm an engineer.
The 2004-09 Prius is a fine functional car with a 1.5L engine. It is best for non-technical car drivers yet offers some interesting options for the skilled. The 2010-current Prius will soon be much more affordable and we have one too.
The 2016 Prius is not available until December/January. NEVER buy the first model year in a strange technology. Wait at least two year (like we will) and let the 'pioneers' work out the initial bugs.
Bob Wilson