Upgrade to 170 BHP with big fuel savings ?

HDI · Post by **HDI** » 17 Jan 2011, 17:14

You should have seen him when I was getting an old Lister CS 6/1 going, it was like he was witnessing black magic !!!

JamesQB · Post by **JamesQB** » 17 Jan 2011, 18:18

Aren't manufacturers now using piezo injectors in diesels, allowing many injections per cycle, which is supposed to improve combustion giving more output for less fuel?

Just thought this may be part of the reason for improved figures. Unless they've already been using them for a while.

HDI · Post by **HDI** » 17 Jan 2011, 18:30

Piezo injectors have been in use for a while and along with electronic control and ultra high injection pressures allow multiple injection events during the power stroke. This indeed vastly improves economy and emissions.

Post by **xantia_v6** » 17 Jan 2011, 18:44

steelcityuk wrote:Just to stir a bit more into the mix, the new Fiat Twin Air petrol engine doesn't have a butterfly in it's induction system either. So what with that and direct injection petrols there's a bit of technology swapping going on.

But the Twin Air does throttle the air, it uses the inlet valves to restrict the air flow and maintain the equivalent reduced pressure in the cylinders, so it is not like a diesel. Fundamentally, petrol just won't ignite (or burn cleanly) at very lean mixtures, but diesel will.

fifth_cit · Post by **fifth_cit** » 17 Jan 2011, 19:25

lussasgraham wrote:has anyone tried one of the chip boxes available on ebay cica £70 that promise more power torque and greater fuel economy?

Before I came back to Citroen, I went on the Dark Side with an Hyundai Tucson 2 .0 CRTD. Smashing car for towing and the wife loved it (always a bonus) but it couldn't pass a fuel station without pulling in.

I tried one of those performance chips and it improved performance greatly but not fuel economy, no matter how I drove it or how I set the economy / sport mode on the chip it never ever did more than 40mpg.

Its still here if anybody wants it !

Keith

PS No one has said that this 170bhp job has a new engine so that makes me think that it is a re-tuned 138 bhp engine which is what I am hoping for.

lussasgraham · Post by **lussasgraham** » 17 Jan 2011, 19:37

funny that the 'chip' company say it will raise the power of a 2,2hdi from 138 to 170bhp so not being a mechanic but i could guess that the fuel maps have been re written on the new c5?

howiedean · Post by **howiedean** » 17 Jan 2011, 19:43

fifth_cit wrote:
lussasgraham wrote:has anyone tried one of the chip boxes available on ebay cica £70 that promise more power torque and greater fuel economy?
Before I came back to Citroën, I went on the Dark Side with an Hyundai Tucson 2 .0 CRTD. Smashing car for towing and the wife loved it (always a bonus) but it couldn't pass a fuel station without pulling in.

I tried one of those performance chips and it improved performance greatly but not fuel economy, no matter how I drove it or how I set the economy / sport mode on the chip it never ever did more than 40mpg.

Its still here if anybody wants it !

Keith

PS No one has said that this 170bhp job has a new engine so that makes me think that it is a re-tuned 138 bhp engine which is what I am hoping for.

Thats not bad for such a big 4*4 is it? What year is your car keith?

Howie

Post by **Peter.N.** » 17 Jan 2011, 20:02

I don't know about all this tuning, its since the manufacturers are squeezing all this power from their engines that that have become less reliable. Look at the BMW for an example, the old 525 diesel was virtually bombproof at 143 bhp now they have upped the three litre version to nearly 300 bhp they are suffering all sorts of problems, turbo failures being just one.

Back to the fuel consumption issue, its only since they substantially increased the power that the consumption has come down. I had may cars using the Perkins 4/108 engine which was 52 bhp, OK in a small car but in anything heavy where you had to use full throttle much of the time the consumption was 30 mpg if you were lucky, the same went for the BMC 1.5, 40 bhp and the early peugeot engines, you were doing around 15 mph per 1000 rpm which meant for most of the time you were driving at well above the max torque and maximum efficiency - and you needed ear defenders.

The first really refined diesel that I drove was the CX, 75 bhp and gearing to match, what a revelation, quiet, refined and economical. Then the XUD, especially the turbo, I think it was that engine that started the diesel revolution.

Peter

HDI · Post by **HDI** » 17 Jan 2011, 20:11

Would agree with the XUD genesis postulation.
Despite kicking and screaming in protest I ended up with a shiny new beige Peugeot 305 GLD as a company car once upon a time, it was my first diesel experience. It was very slow, but I came to enjoy the relaxed performance and greatly enjoyed the economy ! Remember back then that diesel was cheaper than petrol ! You don't see many 305's around these days.

XMV6 sadist · Post by **XMV6 sadist** » 17 Jan 2011, 21:51

Hi

Modern diesels are quite amazing but it's the torque improvements that help the fuel economy as much as bhp. My diesel has twice as much torque as my XM 24v and you hardly have to rev it to make good progress (although it weighs a fair bit more). Hence 40mpg from a big diesel is absolutely standard and long gearing can be used1750rpm @ 70mph.

Tony

Post by **Peter.N.** » 17 Jan 2011, 22:12

I agree, torque is what you need for 'real world' driving, bhp is really meaningless unless you are a boy racer and the high gearing with high, low down torque allows you to drive with the engine around maximum efficiency, as you pass the maximum torque figure, the fuel consumption is increasing as the torque is dropping off, no contest really.

Peter

corsehf · Post by **corsehf** » 17 Jan 2011, 23:37

lussasgraham wrote:has anyone tried one of the chip boxes available on ebay cica £70 that promise more power torque and greater fuel economy?

Yes, i have tried one called 'Diesel Express', has 7 settings but no idea what any of them are??
I was told that setting 3 was near standard (so what are 1 & 2 for?) and that 7 is full power. I was told to change between the settings to see which suits your style best. I wanted economy over anything else so i found that No 5 suited me best but No 7 pulls like a train!!
They do tend to work but not sure what the power outputs are, need someone to test each setting on a rolling road to know.

uncle buck · Post by **uncle buck** » 18 Jan 2011, 00:58

I agree....modern Diesel engines are amazing & so are the dealers / garage at taking money off you to plug it in when they go wrong!

Forget all that fancy black magic & the odd extra mile per gallon as you are going to pay for it in the long run if only in diagnostic fees!

You want a nice 1.9 TD XUD engine....they go for ever & you can fix them yourself!

citroenxm · Post by **citroenxm** » 18 Jan 2011, 08:00

lussasgraham wrote:has anyone tried one of the chip boxes available on ebay cica £70 that promise more power torque and greater fuel economy?

Hi,

Yes I got one on my Xantia HDi... It work amazingly well on the W reg 110bhp that I sold, however, it seems to be having no effect on this V reg 110 HDi I got...

When it did work, the difference was frightening.. ...... well, no, really, it was FUN...

Must look into why its not dooing anything...

The box I have is one of These Box's

Paul

fifth_cit · Post by **fifth_cit** » 18 Jan 2011, 08:41

I have just checked again and the latest version of the C5 2.0 Hdi is 160 bhp NOT 170.
The torque goes up from 236 ft lbs to 351 ft lbs which is where the fuel consumption gains are coming from.

I am not interested in bhp gains and the torque (pulling power) would be nice but I do want the fuel consumption gains.

So back to my original question what are the chances of a Citroen Dealer upgrading my 2008 C5 Tourer 2.0 Hdi with the current software.

I don't expect it for free !!!