By drivetrain I mean gearbox and clutch as well as stuff further down “the line.”

I would love to remap to improve fuel economy, but if you phone a remapper they have this ‘does not compute’ attitude.

JE – what’s your driving style? Struggle to understand this 5mpg improvement.

Simon at emaps understood the economy thing completely. Driving style is “avoid urban areas like the plague during daylight hours, cruise at 70 on the motorway, have fun on the A&B roads, where possible.

Power to weight ratio is obviously better, so you don’t need to drive as “hard” for a given level of performance. The fueling is also set up for the parameters of that specific engine, not a generic “1 map suits all” effort, so it’s using the engine & fuel more efficiently.

95% of the time I don’t use the extra performance, however it’s invaluable for overtaking, and allows the car to justify it’s “sport” badge on the rare occasions I get a clear bit of road.

The 5mpg gain is calculated tank-tank. The OBC is WAY out. Gave me a heart attack when I first got the car and it was reading low 30s mpg. (actually about 40, now on 45+)

mpg gains (or losses) results seem very mixed, even from the most reputable firms.

A mate (who drives very hard) was getting mid 20s in his 335d (usually mid 30s) and eating rear tyres every 5k miles with the car mapped at Evolve.

Power to weight ratio is obviously better

No – MAXIMUM power to weight ratio is better. When cruising at 70, the same fuel is going in to the cylinder no matter what map you have. If you drive flat out like Mat’s mate you’ll be going faster post-remap and hence using more fuel.

I suppose the only parameter to fiddle with is the injection timing. I’m told that timing is retarded in production cars to meet NOx emissions regs, and you can advance it for more power and economy – and they don’t test NOx on a diesel MOT.

molgrips I agree with your comments about drivetrain wear only being a potential issue when making use of the extra power.

But, if you don’t use the extra power fairly frequently then you might as well not get it done….
I was also concerned about lunching through tyres. Mine last about 25k miles at the most on the front, so am changing them every 10 months or less at the mo’. I could do without the fronts lasting even less….

There are definitely mixed results on the SeatCupra website, with some people having no problems at all and others having immediate clutch slip, blown hoses etc. How much of that is down to a lead foot and how much car-to-car variations, I am not sure…..

Agree with Mol. Look at post mapped graphs too – much more “spikey” than factory ones so delivery is often less linear. It’s not all about headline figures.

FWIW energy saving tyres (silica compund like posh mtb tyres) last loads longer than normal ones.

Grip seems great to me but then I am not thrashing a remapped TDI around the lanes 🙂

I had a Discovery 3 remapped, and it noticeably improved the fuel consumption, especially on urban work, as it got to the higher gears a lot quicker. Also took something like 3 seconds off the 0-60 (not that I was especially interested in that), making it acceptable rather than just really slow.

Didn’t cause any problems for the 20k I did with the remap; rather the reverse, it reduced the black smoke that used to pump out of the exhaust under full acceleration.

nick – not saying all remaps are bad. Many seem very good but some cause problems.

A Disco 3 isn’t the most stressed of cars – so a gentle remap isn’t going to trouble it but a highly tuned nippy car is going to be under a lot of strain.

Many people go for them and it’s a big industry now – just not for me.

Almost 300bhp and over 430lbs-ft is quite enough 😉

Surely a remap is pointless if you don’t upgrade tyres/brakes/suspension ? I’ve got a 140bhp VAG diesel and to be honest its plenty quick enough for day to day driving, and would be pointless with more power as its just a standard road car and nothing more speacial than that, or maybe other people just like to go quick in a straight line?

I’d buy a sports car if I wanted more power/better handling etc etc.

True FD. The first upgrade I’d do to my Passat would be some better springs.

Yep FD – very few upgrade their brakes…

Yes although it seems to me that the brakes are the highest spec part of any normal car, being a safety feature and all. Most modern cars I’ve owned can’t accelerate quickly or corner quickly, but all could stop bloody quickly. And yes I know that sports cars have better brakes still, but I am hardly ever full on the brakes when driving on real roads, except for emergencies. If you come barrelling into a corner and apply maximum brakes at the last second on a normal road you need shooting.

Agreed again (!) – in the “old” days, if you tuned up a car, you also upgraded the brakes and suspension. Maybe even stiffened the car too. And is some cases, stuck a heavier duty transmission in. But with all-too-easy chipping, no one (almost) bothers. You have up to 30% more power with the same brakes, gearbox, suspension. Madness.

Towing stuff really highlights the need for brake upgrades too – stopping quickly with a big load utterly kills your stopping distance but few people make allowances. I saw a caravan-towing car overtake a bus yesterday – must have got up to about 75mph on a 60 with a blind corner just afterwards. I cringed big time.

Brakes seem to often get forgotten but they are definitely handy.

Oh, and I upgraded the brakes to Range Sport ones. Made a massive difference.

Agreed again (!)

Gonna have to argue about something soon.

How about that Landy thread? Might have potential.

You have up to 30% more power with the same brakes, gearbox, suspension. Madness

It’s only madness if you really flog it. If you just like a buzz every so often you don’t need be any more dangerous. All depends on WHY you want to remap in the first place. If you understand that a 2.0 TDI Passat remapped is NOT AT ALL the same as an R32, you’ll be reet 🙂

Try and map an R32 and you’ll get nowhere though 😉

Zackly.

Remapped my Golf Estate 1.8T petrol
150 bhp to 207.
Best thing I have every done to a car.
Drive slowly I get 47mpg (previously 36mpg)
Drive hard and get low 20’s
I have had no problems ,does not show up on VAG engine diagnostic check.
Only downside is treating the car to Super unleaded occasionally (most often I just use normal unleaded) to get the best effect and horror tyre wear from wheelspin when driving like a yoof!
Check out VAG forums for the best companies and advice for your model and year of car.

A near 40% bhp rise and 20% mpg increase from a remap? Hmmm… I’d be VERY surprised if those figures are anywhere near true unless it’s had other work done to it.

And if there’s one car with a woefully inadequate chassis, it’s the mk4 (apart from the R32) Golf. At least the 46 4 Motion, with similar power, has AWD and proper brakes… Sounds like a deathtrap to me.

I had my audi s3 remapped 2 years and 20k miles ago, no problems so far, Car has significantly more punch now, it supposedly increased the bhp by about 30-40bhp, but I cant verify that.

Fuel economy is about the same as before, maybe slighty worse, definately not better.

Julians – see 30-40bhp for a mapped S3 is completely believable. A 57bhp increase in an old mk4 Golf isn’t.

Like I say, it’s only a deathtrap if you drive it like a racing car.

Mol – IMO powerful cars need sufficient brakes and chassis to cope. You can get to say 60 quicker so you need to be able to slow down quicker. The extra power also affects the handling dynamics – more power = more over/understeer and torque steer (if FWD) and very few remapped cars also have their DSC programs altered to take this into account. It makes a big difference.

And anyone having their car mapped is likely to be the sort to drive it hard. You can get mpg/efficiency biased remaps but none of the ones mentioned here are that sort.

You can get to say 60 quicker so you need to be able to slow down quicker.

Not at all. If you are travelling at 60 it doesn’t matter how quickly you got there…

And yes I know about torque steer and whatnot. The point is that you MAY want to remap to pretend you have a sportscar on the cheap, but you might just want something for burning out at the lights etc.

If you drive hard, you’ll drive at the limits of your car, whatever they are. If you go barelling into corners too fast, you’re still just as likely to do that in a 140bhp car as a 300bhp car I reckon. The power of your car is very unlikely to be a limiting factor in how fast you approach corners on a public road.

If you were a really really crap driver, I can see you being most likely getting into trouble on a wet road with the torque upsetting the handling, or if you say tried to boot it through a tiny gap on a roundabout or something.

Mol – assume you know about thrust vectors, load of various tyres under different conditions (e.g. acclerating while steering, etc), understeer and oversteer (what causes them, how to deal with them, etc) – some only relevant to fast driving, most relevant to all driving.

A car with more power (compared to the same car with less) is more likely to get out of shape and therefore more likely to need more powerful brakes to sort itself out. A mapped car is likely to be pushed harder (loads will be higher, thrust vector will change, etc) altering it’s handling balance – basically you need better brakes. Anyone that thinks otherwise is dangerous.

IMO sufficient brakes are just as, if not more important than decent power. To up the power without upping the brakes is silly.

Yes mate I understand all that, as I said in my previous post.

What I am saying is that a remapped car is not going to be driven the same way as a real sports car (because it can’t be).

I also don’t think that more power necessitates better brakes. More SPEED and later braking in the run up to corners needs better brakes.

If you bury it out of a corner and start to understeer wildly – where to brakes come into it?

I have 2 VAG TDIs currently and they are both remaped

1st: Octavia 2.0 140PS mapped to c185, power difference is amazing, 0-60 is c7.7 seconds, not tested the top speed but mid range it can keep pace with some silly stuff. Not seen any real world mpg gain in this one though, averaging 46mpg. Remap was done by pendle performance, pulls really well from below 2000 revs where it used to be slow up to 2000, all in all a pretty good upgrade for £275.

2nd Seat Ibiza 1.9 100PS mapped to 150, power difference is utterly astonishing, not tested 0-60 or top speed, mid range is now unbelievable as the car is so light, I had it mapped on Friday and I’ve been scaring myself stupid since. With this one though the mpg has gone up, quite dramatically. I had 48 mpg from the last tank, wierd as the trip computer read 44, now its well into the 50s. Remap was done by Revo for £350. I am going to have to upgrade the front brakes on this one though, probably to performance pads and discs rather than fanny about with bigger discs and calipers though.

Not sure if my experience will transpose to your (op) car, but I’d remap any 1.9tdi again tomorrow at Revo, its a fantastic upgrade for the gains you get, highly recommended

Have you seen how people drive T5 VW Transporters (the nippier ones)?!

A lot of people don’t understand “it can’t be driven fast” so need more help to correct errors.

You mention “burying it out of a corner” (I think I get what that means…) but what about going into that corner?

And why do faster production cars have better brakes? For a laugh?

If it happens to be a Saab that you want sorting, then can highly recommend Abbott Racing. Basically a ‘Gran Turismo’ like list of upgrades and all very good bits of kit!

Also a strong bottom end on Saab turbo engines (older ones) meaning they’re good for 400bhp, but you might need an uprated clutch!

Well going into a corner, the fuel map doesn’t make any difference does it?

My point is that you can approach any corner fast enough to kill yourself in pretty much any car, remap or not.

And why do faster production cars have better brakes? For a laugh?

I’m not saying that brakes are not important for all round performance. I am saying that just because you remap your car, doesn’t mean you are automatically putting yourself in danger.

If you approach corners too fast for your car to cope with, you are putting yourself in danger. That’s perfectly possible in most cars, remap or not.

Mol – I suggest you write to Audi and ask why their 3.0TDI A4 has MUCH bigger brakes than their 2.0TDI Quattro A4 (similar weight).

Then do the same with BMW – a 318d compared to a 335d – again similar weights.

And finally do the same with a Passat 2.0TDI 140 compared to a Passat R36.

Basically remapping is increasing one element of “performance” (the going faster bit) without addressing the other element – the going around corners quicker or the stopping faster bits.

If you accelerate faster, you need to be able to stop faster – applies to riding too.

Mat you are not listening to me.

I AM NOT SAYING BRAKES DON’T MATTER.

So a remap automatically renders the driver unable to judge corner entry speed?

Mol – I suggest you write to Audi and ask why their 3.0TDI A4 has MUCH bigger brakes than their 2.0TDI Quattro A4 (similar weight).

No, the difference in brake disc is 312mm to 320mm, so not much really. Most big VAG cars have the 312 discs on the front, the most powerful have the 320.

I do agree with mat on the last point though though, more power exposes you to more risk if you use it, and more brake power will therefore be required. Of course if you don’t use the power you won’t need the extra brake power. However most VAG cars have adequate brakes for a bit more power, appart from my ibiza, 256mm discs on the front…

God I could bore people stupid about brake disc sizes, I’ve been researching them all day.

It’s perfectly possible to enjoy peeling out without endangering yourself in corners.

djg – I admit that I ASSUMED the disks are much bigger – I’m rather shocked the 3.0TDI only gets 320mm disks! I’ve got 348mm on mine and it’s only a wee bit quicker and it’s lighter too. Even the more similarly matched 330d gets 336mm front disks.

Mol – so once again, why do more powerful versions of the same model car have bigger brakes? Are the manufacturers simply stupid? And what’s “peeling out” and “burying out” of a corner?! Surely if driving in such a safe manner as condoned by you, one eases out at a very sedate pace.

Dunno where to start unravelling that nonsense post Mat.

Brakes matter for high performance, I’ve said that about 50000 times.

A remap does not make a high performance car.

A remap gives you extra power for messing about with.

The rate at which you accelerate from a roundabout say, is not related to the speed at which you will enter a corner on a country road.

I have not condoned anything on this thread. Mentioning something is not the same as condoning it.

Peeling out means accelerating fast and/or making lots of tyre smoke.

Burying it means using maximum acceleration ie burying the pedal in the carpet.

SM, don’t the more powerful cars have bigger brakes as they have a higher top speed?

I suspect some of it is marketing guff as well so the owners of the more powerful cars can feel vastly superior with their tarmac ripping anchors, compared to the less fortunate minions in their less powerful pleb-mobiles. There has to be more ‘performance’ enhancers than just more power.

If I had a remap, I would still drive with the same top speed & same cornering speeds, I’d just have more acceleration if needed/desired. Don’t see why I’d need bigger brakes given that my current ones can easily overcome the grip of the tyres. Perhaps if I intended to regularly drive hard on country roads (which I wouldn’t) or regularly took the car on a track and experienced brake fade I might upgrade the brakes. Otherwise probably wouldn’t bother…

Mol – so a remap gives more power but not higher performance? And you called my post nonsense?

Stump – so explain why BMW puts 336mm brakes on the 330d and 348mm on the 335d. Both have the same limited 155mpg top speed. Other makes do similar… And Jap fast cars have much lower limited top speeds but big brakes…all marketing guff too? No, you are just wrong and trying to get one over me again. Another fail.

I see some cowardly dribble of snot has added a stupid tag again. I’m sorry you lack the ability to explain anything…