J4CKO

iTrader: (1)

Ok, my car falls into Band F at the moment and incurs a charge of £210, next year it goes up into band K and will cost £300 because obviously I am a climate vandal.

However my car has been remapped from 210 bhp to 247 bhp courtesy of BSR, which is a 17% increase in power, if it has affected my CO2 output by 17% then I will be pumping out 255 CO2, which if I am correct (and I realise it isnt quite that simple) puts my car into the top taxatation band (just) for a £400 fee.

Like I said, I expect it isnt that simple, a percentage increase in power will not always incur a comparable increase in CO2 emmissions, I would expect it would go up, more power = more fuel burnt - more CO2 but the new map may be more efficient ?

How will Labor deal with this, it cant of escaped their notice, I suspect they are turning a blind eye as potentially they would need to produce CO2 figures for all combinations of remaps, exhausts and any other aftermarket stuff or do you think they will probably just ban the lot, how would it apply to cars already highly tuned, I have declared my mods (aforementioned map, Pipercross filter) to my insurer, I am tempted to contact the DVLA as a concerned motorist to ask that my car be full examined so I can pay the required amount of road fund due for the CO2 my car is emitting as I think it would be irresponsible of myself and the government to ignore this.

Are the manufacturers going to cotton on, say a 2.0 TDCi Focus, mapped into feeble figures (Say 90 bhp, band B VED) from the factory with an easy and cheap upgrade to the full 140 bhp ?

richs2891

Yes I think that as already has been mentioned on this forumn - see the £950 tax on a new Scoob thread, Manufactors in the short term will bring out a car in detuned form to get it into a lower band and then have a performance pack to bring the performance back.
Longer term they will start to produce more fuel efficent / lower emmisions cars, BMW are already good at doing this.

Richard

pslewis

I doubt very much that a re-map would be more efficient .... the Manufacturer will have made it as efficient as they can in the first instance. A re-map takes away that efficiency in exchange for more power and less reliability.

I like the idea of Subaru selling an Impreza pushing out 100BHP and getting into a very low tax band - then selling you an ECU Upgrade to take it to 225BHP

David Lock

I asked on SN how CO2 emission weights are actually measured. Got zero response. dl

AndyC_772

iTrader: (2)

The band into which your car falls is determined from tests under strictly controlled conditions performed on a brand new vehicle by the manufacturer.

Lots of things can affect the actual amount of CO2 that a given vehicle actually produces in practise - whether it's used in town or on motorways, whether the driver has a heavy right foot, or the condition the vehicle is kept in, for example. And, of course, VED bands completely ignore the single most important factor: how much use the car actually gets.

Having more power available doesn't mean your car actually burns more fuel to maintain a given speed - in fact, many tuning options are actually efficiency improvements, removing restrictions that impede airflow, and thereby reducing the amount of energy wasted.

IMHO the very last thing you should be doing is stirring up that particular hornets' nest. I wouldn't believe that the current organisation would hesitate for a moment to ban any and all car tuning if they thought the environmental lobby knew about it and considered it undesirable. Never mind that the actual differences in CO2 would be minimal in each individual case, and the total number of tuned cars as a proportion of the total is vanishingly small anyway. Almost as bad would be to require all modified cars to be tested in the same way as new ones, it would make any tuning at all prohibitively expensive, yet would achieve nothing more than to devastate the industry and make criminals of all of us.

fivetide

iTrader: (1)

Utter drivel.

The problem with manufacturer settings is they need to hit a middle ground. The car doesn't run at its most efficient or most powerful it settles for a medium.

One of the reasons for this is that government rules on emissions are simply forcing manufacturers to put more and more cats in place to throttle the engine. Therefore to get more or the same power they are having to use bigger engines and more fuel - the reason for Subaru moving from a 2.0 to a 2.5 motor.

If governments went away and simply made manufacturers get more efficient then they would be able to. At the moment they are unable to make a car that runs as efficiently as possible because of the power sapping cats in the system. The rules simply negate themselves.

RiDE did a test on a new CBR 600 junking the three cat exhaust and fitting a power commander to sort out the fueling. The result was an amazing 5mpg and 6bhp increase. If someone can get 5mpg by plugging in a box in their garage imagine what a team of proper techies could do with the budgets they have if they were allowed to do it.

Besides, we allready pay a big engine polluting tax at the petrol pumps.

5t.

speedking

As cats get less efficient with age the CO2 emissions increase anyway. But as stated above a lot of short journeys where the cat doesn't reach operating temperature will increase the 'pollution' to a much higher level than longer journeys.

AndyC_772

iTrader: (2)

Just to be clear: a catalytic converter does NOT reduce CO2 emissions. It increases them, by placing a restriction that the engine has to do work against, and that work requires more fuel to be burned.

GazTheHat

OllyK

Not just that, it converts CO to CO2 and also oxidises any unburnt Hydrocarbons in to, yup, you guessed, CO2 and water. It also breaks Nitrogen oxides in to N2 and O2.

GazTheHat

OllyK =

SirFozzalot

Shark Man

I belive CO2 is measured in simulated "normal" driving conditions

During which a 200bhp car is probably actually giving out 80bhp (an arbitary figure from being driven at part throttle, low rpm, low boost). If the same engine is producing 250bhp due to raised boost levels was tested under the same conditions it will be more or less the same: its capacity is the same as is its compression (or effective compression) during off-boost/cruising conditions. So the output needed to mainatin a certain speed/acelaration rate is the same, so that engine would also output 80bhp during the same test and it'll run the same air/fuel ratios during normal driving so CO2 probably won't be any different (if anything, the AFR may be better due to an individual map - which may drop emissions ).

The only difference will be under full/near full throttle; where there is more boost and fuel mixture enrichment..

Think about it: a car only produces its peak BHP at near peak revs at full throttle. The CO2 is not measured at continuous full throttle at 7000rpm (well, AFAIK ).


Now, what DOES make a difference will be gearing, and weight: Fit a big heavy ICE install, tow a caravan, and fit a gearbox/diff with a low final drive ratio will increase CO2 emssions.

Also if the car had the engine "properly" modified (i.e not just remapping an engine and fitting a diferent turbo ), by that I mean, reworked cylinder heads, different cams, larger valves, lower/high compression ratios etc. - now that would affect the engine's efficiency, its fueling requirements during part throttle/cruise conditions and in turn its CO2.

RJMS

iTrader: (2)

Interesting post and it would seem to make sense but... my UK MY99 has been more efficient (in terms of MPG) on motorway cruises (probably just in boost, certainly not full throttle or anywhere near) since a Zen remap. It's now also got a sports cat which I suppose must help as well

dunx

iTrader: (3)

Remember Toyota developed powerful lean burn engines that used to meet the regulations, but the government forced them to add cats....

DunxC

J4CKO

iTrader: (1)

My god, do not mention that you have a cat, slung under your car that you heat to a 1000 c and blow hot gas through, treating a cat like that will get you infracted !

dnc

I would guess it's calculated based on fuel used, efficiency of combustion etc rather than weighed. If you take your mpg figure for a fuel of known composition you can do a pretty good calc of how much CO2 will be produced in a kilometer or whatever of travel. As OP guessed if your mpg is lower your CO2 per km will be higher.

I may be talking bollox though and they somehow have someone pootling behind cars weighing their CO2 emissions.

dnc

J4CKO

iTrader: (1)

I think its done on a dyno and monitored through a set cycle.

I have a few Trees in my garden, those buggers eat all my emmisions, can I get a discount ?

zs_phil

iTrader: (1)

nothing funnier than seeing a muppet in action

priceless

AndyC_772

iTrader: (2)

Unless someone's managed to invent a car that magically creates carbon out of nowhere, or makes it vanish into a parallel dimension, the amount of carbon that leaves through the tailpipe is exactly the same as the amount that enters through the fuel filler. So in fact, it's directly proportional to fuel used.

I believe that the official test involves putting the car on a rolling road and going through a series of tightly controlled, repeatable sequences designed to replicate typical driving conditions. The car has a gas analyser attached to the exhaust which measures what comes out.

Dream Weaver

The beauty of mappable ignition, especially with 3rd party ECU's is that you can have a map purely for the MOT man and if they were to test modded cars in the future you could have one for that as well.

When my 205 is in for its MOT I simply weaken the fuel mix right down for a few minutes whilst he takes the CO2 reading which bottoms it right down into Prius territory and makes me look like a planet saver

Manufacturers will just run different maps for testing purposes.

scooby2!

sound like a plan to me!!!

scooby2!

Bloody great - dont I work hard enough and pay enough already????????

who said a labour government was a good thing????????? : (

Shark Man

And if you read the line above where you snipped the quote, it gives the reason why.

speedking

The first bit is quite true. However they are measuring CO2, not carbon. Unburnt fuel would not produce CO2. Thus for the same mpg an inefficient engine kicking half the fuel straight out the exhaust would show different emissions to an efficient engine burning all the fuel.

AndyC_772

iTrader: (2)

Agreed - though a car meeting emissions regs must, by definition, be chucking out minimal CO and hydrocarbons. That's what the cat is for.

David Lock

I have found out (thanks 22b) that CO2 is measured under this EC Directive.

EUR-Lex - 31993L0116 - EN

Now of course any child with a Nobel prize in chemistry could easily test a vehicle but I am think the whole thing is completely phucking ridiculous.

Accepting the comments about about unburnt fuel being emitted CO2 is directly proportional to fuel usage. So a car doing 20 mpg chucks out 4 times more CO2 than a car doing 80 mpg.

For some time economy figures have been produced for vehicles which bear some relation to actual driving so why not just use these figures to calculate the CO2 figure. Petrol puts out about 2.31 kgs of CO2 for every litre.

Even if the figures are only approximate it would provide a vehicle comparison which is what is wanted and would be a hell of a lot easier and cheaper than the EC test method.

Anyway my view is that the cost of petrol should be adjusted and road tax eliminated which is fairer all round. dl

J4CKO

iTrader: (1)

I drove like a c*nt this morning to celebrate the bufget, my car wa semitting CO3 just to spite Mr Darling and kill some Eco-kittens.

dunx

iTrader: (3)

LMAO at the above "cat" reference J4CKO, FYI I'm a dog owner so if the car don't f**k 'em the dogs will...

DunxC