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Hybrids, the debate starts here.

Posted: Wed May 16, 2007 3:06 pm
by marktime
Chris has invited me as a Prius driver to start a thread on Hybrids.

I cant possibly put everything in one post so I will start with some general stuff and we can see that questions arise.

First port of call and

There is not much tecnical detail on the web sites however if you request a brochure I am very confident they will offer a test drive and that has got to be a good place to start.

This is a really good site

It was put together buy a guy in the states, it relates mostly to the original MK1 Prius and there have been some subtle changes since then but the technical bit (Understanding the Prius & What's going on as I drive) is very good and anyone who has a single drop of 3in1 oil in their bloodstream will appreciate the engineering that has gone into the constantly variable transmission (It's called the power split device or PSD).

The other place to look is the UK Prius forum

There is a lot of useful information hidden behind mountains of stuff about tyres, engine oil and wheel trims!

more to follow later.......MarkTime

Posted: Wed May 16, 2007 4:29 pm
by ChrisB
Wow thanks for that Mark, just had a little mooch about and was surprised to see the Battery pack is made up of D-Size batteries :shock:

Lot of info in a couple of those links which is going to take me a while to digest :wink:

First question from me is how easy is home servicing ?? is it possible or does the car need specialist computery stuff to reset things ??


Posted: Thu May 17, 2007 11:19 am
by marktime
Thanks Chris, start with an easy one!!

Toyota warranties are very good so think hard before you dig too deep under the bonnet.

The NHW11 model (try to think of that as version 1.1 it will make more sense later) came out on 2000 with a 5 year 60K warranty so you could tinker with one of these if you wanted to.

The NHW20 (v2.0) came out in 2004 and has 3 year 60k warranty 'PLUS' 8 year 100K warranty on the entire hybrid system (Hybrid Synergy Drive HSD) So since you should really stick to Toyota dealers to keep the warranty good you may not want to open one of these up on your driveway.

The NHW11 is commonly known as the 'Classic' and there are several contributors on the yahoo forum who know a great deal about how it is put together. There are some lists of error codes so it is possible to PD some problems without interogating the onboard computers.

In case you are wondering about V1.0 it was only ever available in Japan, they do appear elsewhere as grey imports. All the display info in the car is in Janpanese (there is no conversion) and UK dealers are unlikley to service them but there are ways to get parts I think.

Time to own up, mine is a company car (it's a HNW20) warranty and servicing are not my most critical factors, however from reading the yahoo forum for nearly a year before I got mine I was stunned that the biggest complaint about quality / reliability was that the alloy wheels are prone to corrosion (behind the plastic wheel trims). These are nearly always replaced under waranty.

Had enough yet.......more later Mark

Posted: Fri May 18, 2007 4:58 pm
by ChrisB
Had enough , nah :lol:

Owning it as company car isnt a sin , makes it great in my book, its like having one long test drive :lol:

mmm I did wonder if now we are about 7 yrs down the line the early ones where begining to get into the DIY'ers garage.

I've seen a few on Ebay but they always seem to fetch good money even a broken 2001 vehicle got about 3K from memory which is still to rich for me to tinker with.

I'll keep digesting the links you put up and see if I can come up with any other questions


Posted: Sun May 20, 2007 6:52 pm
by marktime
I will be wayfrom the tube for a few days but will put up some more stuff on Wenedsday if I get the chance.


Posted: Wed May 23, 2007 11:03 am
by marktime
Hello again, just to keep things fair I thought I would put up a few words about the Honda Civic Hybrid as the Prius seems to get all the press (good and bad) the HCH is a bit of a Cindarella.

I had a test drive of the HCH when I was making my decision and while it didn't 'do it for me' it has some good points.

Unlike the Prius the HCH has it's electric motor built into the engine's flywheel. This means neither can drive the car independantly. however the concept of an undersized ICE suplemented by an electic motor is the same, with a 1.4 engine where you would expect to find a 1.8- 2.0 litre engine.

Both are good sized family cars with 5 seats the HCH is a saloon with a boot, the batteries are under / behind the back seats so the seats do not fold down, the lugage space is not very flexible.

The brochure says that the HCH is available with either auto or manual transmission but I got the impression that the manual is very hard to get hold of, I could be wrong.

In the drivers seat it is just like a conventional automatic car. Auto shifter in the centre console with reverse, park, drive, sport and limited change setting. The handbrake also lives in the centre console.

Hit 'start' stick it in drive and off you go! There is a battery state gauge that shows if you are drawing power out or pushing power into the battery and how much you have, there is always a direct relationship between your speed and the engine revs (this is not the case with the Prius and it worries some people). If you are able to adopt a smooth, predictive driving style you will get good MPG (circa 55 to 60). The only real party trick the HCH has to offer is when you pull up in traffic the engine will stop, it will restart (instantly) when you take your foot off the brake, I found a minor flaw with this. When you first join the end of a line of traffic it stops, it is then very common for the queue to shufle forward about a car length, the engine starts as you take your foot off the brake but now when you stop again the engine is less likely to turn off, I suspect this needs more work on the predictive driving style, the trick is not to arrive at the end of the queue until after they have had a little shuffle!

All this starting of the engine is done with the motor / generator built into the flywheel so there is no need for a starter motor and the starting process is silent / very quiet. The onboard computers also have the ability to shut down a couple of cylinders on the engine when electric motor is able to provide the balance of power.

In summary

Combined MPG Prius wins 65.7mpg vs 61.4mpg.
CO2 emissions Prius wins 104 g/km vs 109 g/km but both are in VED band B* (£15) and as company cars would be taxed at 10% oftheir P11D value.
Price Honda wins £15600 vs £18600. (middle option T4)
Load space Prius wins 408L vs 350L.
Things that matter less.

Max speed Honda wins 115mph vs 106 mph
0 – 60 Prius wins 10.9s vs 12.1

Most physical dimensions are identical or within 10mm

* VED band B is for vehicles producing between 100 and 120g CO2 / Km and is £30 alternate fuel vehicles have a further reduction and come in at £15.

The HCH is not the same body shape as the current 'new civic' and is a bit 'nondiscript' to look at (I have not knowingly seen one since my test drive) in fact it would pass for a 'normal' car in almost every respect and that could be a good thing.

There is nothing 'normal' about the Prius it is 'technology on a stick'!

more later.........MT

Posted: Wed May 23, 2007 11:24 am
by ChrisB
That is a great write up Mark 8)

Interesting that you say the Honda cant run excusively on motor alone due to it being built into the fly wheel .............I didnt know that

As you mention it does seem like they need to refine the start stop drive cycle on the computers somewhat.

I followed a prius back from work the other day and chased the poor bloke back to his house in the van.
When he had stopped and got out I went up to him and attempted to have a bit of a chat with him about the car, but all I got out of him was it was his company car and when asked why he chose it , he replied well it helps the environment doesnt it and with that scuttled off inside his house :roll:

Wasnt really that excited about talking to me at all :roll: but then I suppose if some nutter follows you home in an electric van what does one expect :lol:
But I had hoped for a bit more enthusiasm about his and my vehicle than I got :cry:


Posted: Wed May 23, 2007 5:18 pm
by marktime
Chris, I have had a few conversations with people who have expressed an interest in car parks or on petrol station forecourts (I was trying to remember how the pump worked)! I would be a bit wary if someone followed me home but they would get my attention if they had an EV.
When I went to view the City EL's in Yapton I mentioned that I drove a Prius and ended up taking him for a spin around the block, he was very interested in the car and said he had seen them before but had not realised what they were.


Posted: Wed May 23, 2007 9:49 pm
by ChrisB
You cant be far from me to be honest, I'll drop you a PM :wink:


Posted: Fri May 25, 2007 11:36 am
by marktime
Ok I've beeen beating about the bush long enough, time for some real life 'driving a Prius' stuff.

I mentioned that on the HCH the centre console was like a normal car well on the Prius it's not. The centre console is just an arm rest and has some handy storage. The drive selector is on the dash and the parking brake is on the floor!

There is a standard set of instruments directly in line with the driver, these are actualy projected upwards from inside the dash. You get speedo (digital) fuel gage and various lights, no temp gauge.

There is also a Multi Function display (MFD) on the dash in the centre of the car (I will try to put up some photos later). The MFD gives access to the controls for the audio system and the climate control it also gives 'Trip info'

Trip info can display two screens of info, there is the 'Energy' display and the 'Consumption' display.

When you first encounter the Prius you only ever want to look at the 'Energy' display after time the 'Consumption' display will take over your interest.

The 'Energy' display is a 'Graphical representation' of what is going on between the road wheels, engine, electric motors and battery.

The energy display shows animated images of the power flow between the components with moving arrows.

Let's drive somewhere.

The system is on (ready) and we will assume that the engine is already warmed up and has stopped.
The drive selector is a toggle switch on the dash, put your foot on the brake and toggle down for drive. Lift your foot off the brake and the car will creep forward (Toyota wanted this car to act like a conventional auto so it creeps, they could have made it stand still). Give a bit of gas and off we go, silently, the energy display will show arrows from the battery to the electric motor and on to the road wheels. Accelerating gently to about 35MPH the ICE will start (you wont hear it of feel it) continue accelerating and you will hear the engine note rise.
When you lift off the gas the electric motor will become a generator and give charge to the batteries (you EV guys know this stuff so I wont do detail).

If we slow down and stop the ICE may shut down before we come to a standstill, it may still be running, it can stop and start at any time. If we selesct reverse (toggle up) there is no mechanical reverse gear we use only electrical power but the ICE my run if the battery needs charge.

Going forwards again if we accelerate hard or are going up a hill both ICE and electric motors will work together the engine note often appears to be out of step with the speed of the car i.e. the engine note may lag behind or remain high after we back off.

I know that there a lot of other very interesting things going on on this forum right now so I will stop now and see if there are any questions.