Petrol v Diesel

veronese68

Pufftmw wrote:

Why is chipping "cheating"? I had a custom (to my car) tune, not just an eBay "box" job. It did indeed make it smoother, faster and more economic as it mapped the car better to its capabilities, not just enter a manufacturer "safe, one size fits all" map. I'm just taking advantage of the potential of the car. The £500 cost has more than been recouped in fuel saved.

Sorry, pulling your leg. Couldn't resist. Getting a diesel remapped is the best improvement you can do and I would if I had one.
Regarding fast cars feeling slow. It's all in the power delivery. We had a supercharged MGB here, it felt really slow abd dull. But it could top 125mph. A tuned MGB with big carbs and a high lift cam feels faster, but really is dog slow.
The VAG 1.9tdi engine seems to have an inifinite number of power options. I'm pretty sure the only difference between each one is mapping.

EKE_38BPM

I've got a friend who chips and tunes cars. On one of his cars, he has various different maps, depending on how he wants to drive that day. One of his maps is an economy map that takes the engine down from a potential of 500bhp down to ~80bhp.

He doesn't always want to drive like his hair is on fire!

CambsNewbie

A diesel normally costs about £1,000-£1,500 more than the equivalent petrol model and service intervals can sometimes be less and cost more and then the fuel itself costs more..

I think the what car? Website has a comparison table for petrol v diesel. Some diesel models you need to do 60k+ miles before you even break even..

mudcow007

plus when it goes wrong petrol is cheaper to fix**

realistically in a petrol car it will be coils.. = cheapish

diesel -
Fuel pump = £1000+
Turbo = £1000+
DPF = £1000+

although diesel cars do last longer than petrol cars generally

**this is from my own experience

greg66_tri_v2.0

walkingbootweather wrote:

The time to replace my car is drawing near. Because I cycle, the car only does modest mileage, generally less than 10,000 miles annually, and sometimes the car isn’t used for several consecutive days. Conventional wisdom suggests that for low mileages petrol is a better option, hence I have only ever owned petrol cars in the past.

My simple maths suggest I would save about £600 per year on fuel by swapping to diesel, and that it would take 3 years to recoup the additional outlay, but that then I would probably get a better trade-in on the next car. Friends that drive diesels say that modern turbo diesels are no longer the noisy, smelly machines of yesteryear and that they prefer the driving characteristics and mid-range grunt over petrol.

I’d just about decided to make the switch then someone warned me that the real-world mpg of diesel is often wildly short of advertised, meaning that running costs are in fact quite similar, and that unless you are having regular, long, high-speed runs that the diesel particulate filter can clog up resulting in problems and big bills.

I’m guessing many on here are in the same boat as me, mixing cycle commuting with driving, and doing modest but mixed driving (lots of trips of a few miles, 3 or 4 longer runs every month, and a few major mammoth jaunts each year). Do you drive a petrol or a diesel motor? What would you get in my position? If you have a diesel and don’t do lots of miles, have you had any problems with the DPF?

IMO you've identified precisely the reasons why petrol would be better for you. Diesel sounds like the better choice, but for that mileage and type of driving, I'd have petrol every time.

I'm quite surprised that the premium to buy a diesel over the equivalent petrol car is only 1800 or so. I would expected it to be higher. Whenever I have dome similar sums I end up concluding that I'm looking at 5-7 years to recoup the premium.

greg66_tri_v2.0

DonDaddyD wrote:

OK I just found out that I'm getting roughly:

12 liters/100 miles = 37.8840833 miles/gallon(UK)

That ain't good, is it?

Errrr, yes.

Try running a V8 and a flat six (although that's better that the two V8s we had before that). You would dream of a figure that high.

greg66_tri_v2.0

Pufftmw wrote:

I've got a "chipped" Volvo XC70 2.

How much extra did your insurer want out of you for that?

rolf_f

walkingbootweather wrote:

Not a Saab by any chance Rolf? Actually now that they have gone into administration Saabs do look stonking value, and for the 9-3 at least spares should be OK to get hold of.

Probably are. I keep to the older stuff myself. Quality is far better and costs far less - I regard a four figure repair sum as something that includes a new engine - fitted . The exception is fuel. The 8v Turbo is a bit of a guzzler but that doesn't matter much with the miles I do.

This reminds me - must renew my insurance. £200 fully comp!

veronese68

Got to admire Saab for taking a piece of shoot TR7/Dolomite engine fitting it backwards to drive the wrong wheels and making it reliable. Absolute genius.

SimonAH

I have to say that if I were buying a car on my own dollar right now a Jag S Type with the big diesel would be high on the list.....cheap as chips and what a mile muncher.

rick_chasey

Veronese68 wrote:

Got to admire Saab for taking a piece of shoot TR7/Dolomite engine fitting it backwards to drive the wrong wheels and making it reliable. Absolute genius.

Hasn't stopped them going bankrupt twice.

veronese68

Rick Chasey wrote:

Veronese68 wrote:

Got to admire Saab for taking a piece of shoot TR7/Dolomite engine fitting it backwards to drive the wrong wheels and making it reliable. Absolute genius.

Hasn't stopped them going bankrupt twice.

Mechanical genius when they really were Saab. Unfortunately being good at engineering doesn't make you good at business, often quite the opposite. The two are almost mutually exclusive.
GM making them go belly up was GM's fault.

EKE_38BPM

Veronese68 wrote:

Rick Chasey wrote:

Veronese68 wrote:

Got to admire Saab for taking a piece of shoot TR7/Dolomite engine fitting it backwards to drive the wrong wheels and making it reliable. Absolute genius.

Hasn't stopped them going bankrupt twice.

Mechanical genius when they really were Saab. Unfortunately being good at engineering doesn't make you good at business, often quite the opposite. The two are almost mutually exclusive.
GM making them go belly up was GM's fault.

I think I remember hearing that every Mini ever made (real Minis, not the BMW things that BMW won't put their name to) was sold at a loss. If that is true, wow!

SimonAH

EKE_38BPM wrote:

Veronese68 wrote:

Rick Chasey wrote:

Veronese68 wrote:

Got to admire Saab for taking a piece of shoot TR7/Dolomite engine fitting it backwards to drive the wrong wheels and making it reliable. Absolute genius.

Hasn't stopped them going bankrupt twice.

Mechanical genius when they really were Saab. Unfortunately being good at engineering doesn't make you good at business, often quite the opposite. The two are almost mutually exclusive.
GM making them go belly up was GM's fault.

I think I remember hearing that every Mini ever made (real Minis, not the BMW things that BMW won't put their name to) was sold at a loss. If that is true, wow!

I know all mine have been! Keep restoring and tuning the little blighters only to sell them for way less than the parts and labour put into them because something else shiny comes up and I need the garage space!

veronese68

There's a famous story about when David Brown ran Aston Martin a long way back and a friend of his went to see him at the factory with a view to buying a car. He said he'd buy one but when told the price said he'd only be prepared to pay cost, not retail. After some workings out the cost price was come up with at about £1,000 more. Considering a new Aston was about £5,000 at the time it was quite a difference.

EKE_38BPM

A few years ago I saw a highly tuned Mini with twin centre exhausts (1275GT?) accelerate away from a roundabout. The twin jets of blue flame from the exhausts made it look like a jet fighter on afterburner.

Looked cool, sounded great.

rolf_f

Veronese68 wrote:

Rick Chasey wrote:

Veronese68 wrote:

Got to admire Saab for taking a piece of shoot TR7/Dolomite engine fitting it backwards to drive the wrong wheels and making it reliable. Absolute genius.

Hasn't stopped them going bankrupt twice.

Mechanical genius when they really were Saab. Unfortunately being good at engineering doesn't make you good at business, often quite the opposite. The two are almost mutually exclusive.
GM making them go belly up was GM's fault.

I think the 900 was hugely expensive to make by the time it was discontinued (24 years after the basic design was introduced) so was almost certainly costing the money before GM took over. Trouble is, GM removed everything about the brand that made it different and the public of today aren't interested in the sort of things that made Saab different - so the company would have been stuffed anyway. The public would rather have a crappily made car that has nice mock alloy fixtures that do look quite snazzy than something that looks a bit basic but actually really is good quality underneath. Apparently, if you break the windscreen on a 900, you can re-use the screen rubber. I respect that!

CiB

EKE_38BPM wrote:

I think I remember hearing that every Mini ever made (real Minis, not the BMW things that BMW won't put their name to) was sold at a loss. If that is true, wow!

That was Ford. They couldn't believe that the Mini could undercut their Anglia so stripped one and costed it down to the washers, concluding that there was an approximate £30 loss on every Mini that was sold.

I remember the furore when the price of a new Mini crept above £1000 for the first time. Outrage.

The Rookie

'Chipping' Diesels can work well, but there are some Cowboys out there, when I was at Ford we had a Focus TDCi chipped by one of the biggest chippers in the country, what a bodge job
1/ Boost was increased above the MAP sensors ability to measure so it was merely being guessed at
2/ Fuel was increased beyond the airflow anyway, it failed the MOT smoke test despite the car only being about 5 months old and in perfect working order
3/ EGR was reduced so it was an illegal modification as it would fail a homologation style emission test
4/ Mid range torque was so high it was ripping the centre out of clutches (it went through 3), if a beefier clutch was fitted it was producing far more than the transmission could cope with reliably anyway.

Chip by all means, but do it advisedly!

2 cars, a Subaru turbo (25mpg on a good day) and a Mazda RX-8 (hmm 22mpg once!)....

Simon

mar_k

EKE_38BPM wrote:

I've got a friend who chips and tunes cars. On one of his cars, he has various different maps, depending on how he wants to drive that day. One of his maps is an economy map that takes the engine down from a potential of 500bhp down to ~80bhp.

He doesn't always want to drive like his hair is on fire!

May I ask what car your friend owns

gtvlusso

mar_k wrote:

EKE_38BPM wrote:

I've got a friend who chips and tunes cars. On one of his cars, he has various different maps, depending on how he wants to drive that day. One of his maps is an economy map that takes the engine down from a potential of 500bhp down to ~80bhp.

He doesn't always want to drive like his hair is on fire!

May I ask what car your friend owns

I have a friend who re-built an old 5 cyl Audi S2 engine with a turbo the size of a dustbin, balanced crank and 2.5 litre re-bore from the original 2.2 litres - up to 750BHP on tap, however, it was only 'usable' at about 500bhp

He placed the engine in an old Audi 90 that had quattro system, bought for £200 - had to upgrade the brakes to Porsche calipers and disks.

The clock on the car only went up to 150mph....the car could do near 190mph....

It was lethal. He sold it and bought a scooter - 2 to about 5mpg was killing him financially (yes, 2 to about 5mpg!)

davis

bails87 wrote:

I'd just do what I do, once every couple of weeks give it a good blast, just a 'racing start' and then some high revs, e.g. leave it in 3rd to accelerate up to 60*, rather than changing up to 4th and 5th like on a more leisurely start.

Careful, I've just replaced the dual-mass flywheel on my 1.8 TDCi Focus as it broke apart -- apparently "enthusiastic" starting can accelerate this. I went for a solid-piece flywheel as it was less likely to go wrong -- this makes it sound and feel even more agricultural!

bails87

davis wrote:

bails87 wrote:

I'd just do what I do, once every couple of weeks give it a good blast, just a 'racing start' and then some high revs, e.g. leave it in 3rd to accelerate up to 60*, rather than changing up to 4th and 5th like on a more leisurely start.

Careful, I've just replaced the dual-mass flywheel on my 1.8 TDCi Focus as it broke apart -- apparently "enthusiastic" starting can accelerate this. I went for a solid-piece flywheel as it was less likely to go wrong -- this makes it sound and feel even more agricultural!

Thanks for the heads up.

'Racing' may have been a bit over the top. I just meant foot on the floor, finishing with high revs, no wheel spinning or anything!

mar_k

Pufftmw wrote:

Have diesel, get good fuel economy out of it, pootle around in town around 25mph and never have had a problem with the DPF in the 7.5 years I've owned the car. Last year did under 8000 miles with 1000 of those being commuting I would have said.

what year is your car?
The reason I ask is DPF filters didnt have to be fitted to cars until 2009,
A few car companies started fitting then earlier than '09 as they anticipated the rule change, however not too long before '09. Your car most likey doesnt have a DPF if it was made before '07.


Also one thing worth noting, It is possible to remove the DPF on modern diesels and still pass the emissions test.

Many tuning companies can safely delete out the function of the EGR valve and remove the DPF without it affecting the emissions come MOT time

walkingbootweather

I tend to alternate between 'interesting' but sometimes impractical or expensive-to-run vehicles including original Mini, big Lexus, Nissan eGT, with more worthy but less interesting transport (most of which I have forgotten or am too embarrassed to mention). Partly this is influenced by lifestyle - when I was younger there was lots of gallivanting all over the place, these days there is more ferrying kids to their respective activities at more sensible speeds. It would be nice to find something that brought a smile to one's face and was practical. A diesel with plenty of torque looked like it might be the answer, but the verdict here seems inconclusive. Mrs WBW didn’t get on with autos, and likes something that she can park. I need it to be big enough to take the family on holiday or a bike or two in the back (not necessarily at the same time). As someone who learnt to drive when seat belts were optional, and manual choke was de rigour, I’m amazed at how good modern cars are.

An engine re-map or removal of the DPF look like useful ways of improving performance and economy of turbo diesel cars, but I think I’d be frightened of invalidating warranty or insurance.

davis

Skoda Yeti. Job done.

mar_k

Not a problem on the insurance side of things,
If you have the car mapped to increase power you will need to declare this at the time of taking the insurance out,
If its just to delete the Egr function then your not increasing power, just getting rid of a problem.
The warranty would be the only issue I can see.
The DPF it self would still be inplace so you may get away with the warranty. Its the inside of the DPF that is removed

bails87

mar_k wrote:

what year is your car?
The reason I ask is DPF filters didnt have to be fitted to cars until 2009,
A few car companies started fitting then earlier than '09 as they anticipated the rule change, however not too long before '09. Your car most likey doesnt have a DPF if it was made before '07.

Really?

I know the 1.6 and 2.0 l versions of my car (2005-) both had DPFs. Mine might be one of the 'few', but it's not like Ford are a minor company!

walkingbootweather

davis wrote:

Skoda Yeti. Job done.

but a petrol or diesel one :?

mar_k

bails87 wrote:

mar_k wrote:

what year is your car?
The reason I ask is DPF filters didnt have to be fitted to cars until 2009,
A few car companies started fitting then earlier than '09 as they anticipated the rule change, however not too long before '09. Your car most likey doesnt have a DPF if it was made before '07.

Really?

I know the 1.6 and 2.0 l versions of my car (2005-) both had DPFs. Mine might be one of the 'few', but it's not like Ford are a minor company!

Ford did fit them to the Focus and C-max for some stupid reason