Increasing a cars BHP?

racso1975

I am going to be getting and Audi 1.9tdi and it will most likely be the 100bhp model. Could somebody please tell what realistically i could increase it's bhp to and how this is done and possible effects on the car. I do not wish to alter the external view of the car. By the way i m a complete novice re this topic. so please eep it simple amd many thanks in advance

Duff

You could get its ecu remapped quite easily getting another 30-50 bhp.

Blitzkrieger

What he said. Probably increase your fuel consumption and decrease your service interval but what doesn't?

FOGOFUNK

Depends just how drastic you want to be, remaps as said are the easiest, but you can do lots, performance exhaust manifolds, bigger turbo, new intercooler, new fuel injection systems....... the list is endless.

Andrewf20

My brothers Seat Alhambra 1.9tdi is getting remapped soon from 115bhp to around 150bhp. Cost? 325euro all in.

ShowUsYourXbox

Lose some weight and stop visiting the bear gut forum :P

OKenora

The best "bang for buck" solution is a re-map. A decent re-map will add about 40bhp to the Audi but more importantly it will add about 60lb/ft of torque. It will also change the power band of the car and the way it delivers that extra torque making the car feel a lot faster than the 40bhp would indicate. It is the single biggest change to BHP you can make to your car (bar an engine change ) RULES OF RE_MAPPING - only get a well trusted reputable company to do the re-map, may cost more short term but longterm you will appreciate the extra few euro spent.

Other mods that can release a few more BHP are an improved exhaust system and an improved induction system for the engine but the increases are very minimal compared to a re-map and the cost is very high and not justified unless you want every last BHP wrung out of the engine.

Getting your car re-mapped WILL NOT affect your MPG or your service intervals so ignore that mis-guided rumour totally. What will affect the MPG and service intervals is how hard you drive the car i.e. your driving style. This will affect both your MPG and service requirements even on a non re-mapped car.

When you re-map it is tempting to use the extra grunt all the time and this will affect the MPG, same as if you thrash the standard engine all the time.

Biggest downside of a re-map on a diesel is exhaust smoke on hard acceleration, though a decent re-mapper should be able to stop this or at least reduce it to an acceptable level. I imagine it would be possible to fail an NCT/MOT on this but if the re-maps that bad I would seriously question if I had got the right person to do the re-map.

Any re-map on the car is 100% reversible with no side effects (again presuming the guy knows what he is doing)

Blitzkrieger

OKenora wrote:

Getting your car re-mapped WILL NOT affect your MPG or your service intervals so ignore that mis-guided rumour totally. What will affect the MPG and service intervals is how hard you drive the car i.e. your driving style. This will affect both your MPG and service requirements even on a non re-mapped car.

That's kinda like saying buying a lot of icecream won't make you fat - but eating it will. I know you explain why it doesn't have to affect MPG and service intervals but realistically it will.

racso1975

Ok so the audi did not work out and did a complete u turn and got a xsara 2 litre HDI......is it still posible to do the above with this car

OKenora

realistically it will.

Realistically IT WON'T, read the post....

If you thrash your standard 1.9 CDTi you will get about 35-40 to the gallon and would be advised to have more regular services, drive it easy you will get 40-45 mpg

If you re-map the car then......

If you thrash your re-mapped 1.9 CDTi you will get about 35-40 to the gallon and would be advised to have more regular services, drive it easy you will get 40-45 mpg (or more)

A good re-map is far far more than simply dumping in more fuel to the engine, there are many factors that affect power fuel being simply one of them. A good re-map shifts/extends the power band meaning less throttle in normal driving which will give an INCREASE in mpg and it can reduce flat spots that would originally have meant you used more throttle again helping to INCREASE mpg.

A better analogy than yours would be eating does not make you fat, overeating does. Having a re-map does not adversely affect MPG, thrashing a car does regardless of a re-map or not. In fact if your driving style is respectable and does not change from before to after the re-map then your MPG can often increase rather than decrease. Perfect example is my current motor, quite a hefty re-map and some mods too but MPG has increased about 2-3 mpg on average since re-map as I no longer have to use as many revs to acellerate just as quickly.

About the Xsara, yes it can be re-mapped just as easily, expect a 30-35 bhp increase and a 45-50 lb/ft torque boost depending on the exact 2.0 HDi model.

Zascar

the best and easiest way is simply to buy a faster car in the first place, you'll be glad you did.

Blitzkrieger

OKenora wrote:

MPG has increased about 2-3 mpg on average since re-map as I no longer have to use as many revs to acellerate just as quickly.

TBH it sounds like your car was badly tuned to being with. You just cannot get something for nothing. If you're accelerating quicker without using more fuel the mix must not have been right to begin with.

nastysimon

This is something I find a little odd. Let's take VW, a company with great engineers (well they can afford to hire them, even if they don't have too many themselves) who know how to get the most out of their engines. Now, some guy running a moding shop (at best a technician, at worst a cowboy) modifies the map so it gives you say 25% more bhp, and better MPG, and no worse engine life. I just find that hard to believe. I know that some of the practices that go on in car companies are a little dodgy, but the fact is that they are the engineers who push the envelope with every car they develop. You would think that they would have tinkered with the fuel settings and gotten within 15% of the optimal, ok they may have made some trade-offs, but to be so far out that there is no benefit with their map over one that some bloke spent a few days putting together in his garage, well that would be such a terrible damnation of their skills. Would you trust them to develop suspension systems, or brakes, or anything else on your car if they couldn't get their own fuel injection system better setup than some engineer wannabe?

OKenora

You are making the 2 biggest assumptions you can make as the basis of your argument, unfortunately both are wrong.

Firstly you should note I say a "reputable re-map", these are a long long way from some kid fiddling blind with a few settings to get more power which is what you assume is happening. While maybe not multi million pound operations a good re-mapper will do as good or better a job than the factory engineers. My car was done at Monza Motorsport, check out their customer list and you will recognise a lot of the names. They are a long way from being amateurs that don't know what they are doing.

Secondly you assume that the cars are tuned from the factory for maximum power, again this is not true. The cars are more likely de-tuned to pass emission regulations. There is much room for improvement on a standard map, as the cars generally have to run on the same map in a global market meaning they may not be at their optimum tune (most likely they are very conservative) for the conditions we have in Ireland but are like this to survive the conditions in say Saudia Arabia which are climatically a bit different to here.

Argue the point all you want, but using lower revs on any engine WILL improve MPG. Having more torque available will let you use lower revs. Re-maps shift power bands quite well meaning you can use lower revs a lot. Previously a change down to 4th for an overtake can now be done with the extra torque at lower revs in 5th, simple changes that make a lot of difference. Maybe you would like to explain how a re-mapped car revving to 2500 revs in 5th will generate more wear than a non-re-mapped car revving to 3500 revs in 4th to perform an overtake ?

You don't get something for nothing though as you point out. One of the biggest losses though is the green friendliness of the car as emissions will probably exceed the original specs and may in some cases not even be within the legal specs.

Mostly on diesels there is an increase in turbo boost as a major source for more power (remember a re-map may not always be for more power), but 99% of modern diesels run a very modest standard boost well within the specs of the engine and turbo. On a good re-map this is increased but still nowhere near turbo or engine blowing levels. Maybe (only maybe) over very long term there will be extra wear on some components but no more so than the original manafacturing tolerances would have had between different units, i.e if your turbo would have failed at 100k then maybe the re-map would make it fail at 98k but I could still find you 100's of the same model that had failed at less than 98k with no re-map at all.

What gives re-maps a bad name is people getting it done and thrashing their car then when it goes bang blaming the re-map, failing to realise the car would have done the same anyway without a re-map due to their driving style.

the mix must not have been right to begin with.

Exactly my point, but you are presuming the car maker got it right....this is the single biggest incorrect assumption you can make. If you don't believe me, drive a standard Alfa and get used to the flatspots in the rev range where the car is burning fuel but not delivering power, then drive the same model with a re-map and notice these smoothed out. Cars mass produced have to be jacks of all trades, a re-map should be a custom one off for a particular car and should work better. It 's like the difference between the fit of an off the peg Dunnes Stores suit and a Saville row hand made suit.

Please note we are not talking about the guy with the laptop in the backstreet garage, they aren't proper re-maps. the experience i describe is one of a proper re-map not a generic re-map and while a generic one will work i would be tempted to go for a far more conservative map with that than a true custom map.

And get some reading skills....i said....

okenora wrote:

I no longer have to use as many revs to acellerate just as quickly.

Which you read as...

blitzkrieger wrote:

If you're accelerating quicker without using more fuel

Not quite the same things are they ?

Blitzkrieger

OKenora wrote:

Not quite the same things are they ?

Here's where we go into reading comprehension. You said you accelerate faster and said your mpg has improved. Are these not connected?

I completely agree with most of what you're saying but explain to me where the extra power is coming from if you're not burning more fuel? If you're just upping the boost from the turbo it's not going to give you much without increasing the fuel flow too.....and the spark if you're really going to extremes. And if you up the turbo boost, how long before you have to modify the exhaust system? Is a skilled remapper able to defy the laws of physics?


I also can't believe IR are still going Are you a CS clan now?

OKenora

You said you accelerate faster

No I didn't, I said it can acellerate just as quickly but using lower revs, therefore implying a higher gear and at lower revs less fuel usage. Take a car crusing at 1400 rpm behind a caravan in 5th. A lot of cars when floored at this RPM will simply not respond and the driver will mostly be tempted to dropping into 4th gear, higher revs, up into the power band of the engine and overtake. If you shift the power band of the engine down so that the power is available at the lower revs in 5th then he will not have to change down the gear, lower revs and better fuel economy. Remember golden rule 1, manafacturers tune for emissions in preference to near everything else these days, and definitely not for performance, in "normal" road cars anyway, they DON't always get it right, either by design or mistake.

You assume that the only way to get more power out of an engine is to squirt in more fuel but it's not that simple. Timing of the injection and the length of the injection also make a difference. If you simply squirted in more fuel all you will get is unburnt fuel leaving your exhaust and little if any more power. This is also one reason why you can get far greater power gains off a turbo car than a normally aspirated one. In a turbo you can control/change the amount of induction (increase boost) and thereby run with more mixture in the cylinders, on a normally aspirated car you cannot control the induction in this manner so they show far smaller gains from a re-map, but still can benefit from one and feel faster and more driveable as a result.

As to the exhaust and induction sides, yes I agree they do need attention for the best results (mines been done) but most standard exhausts will provide a sufficient flow for moderate increases in power. You really only need to consider a new exhaust if either you are going for an extreme map or the stock exhaust is a piece of dung to start with (rule number 1 applies again, the manafacturer does not always get it right). The induction side is easily addressed at little cost and if you spend hundreds of euro on a re-map surely you should at least stretch to a better less restrictive air filter at the same time...with possibly a colder feed too, it's amazing the amount of cars that draw in their air from close to an exhaust manifold (rule No 1 again)

Blindly trusting your car maker to get it right is a really bad idea...don't beleive me ?....what about the audis with wishbones failing at sub 20k, the first Merc A classes tumbling over, Alfa timing belts lasting silly small mileages because they got the tensioners wrong ? You expect these guys to design engines perfectly and optimally yet in some cases a car manafacturer cannot even design a bonnet catch that holds the bonnet closed.....none of the above are high mileage failures but all examples of bad original design by companies that would be at the more respected end of the car market....I am sure there are hundreds more examples of crappy design out there, covering from Alfa to Zonda, thats just a few that came to mind.




LOL at [IR] blitz Dunno whats happened to them, not been online gaming for years now.

Blitzkrieger

OKenora wrote:

No I didn't, I said it can acellerate just as quickly but using lower revs

pfff - semantics. I still don't think you're adequately explaining where the extra power is coming from.

I think it's irrelevant anyway because my icecream analogy will hold true. The car might not be thrashed but odds are it'll be driven more aggresively.

OKenora wrote:

LOL at [IR] blitz Dunno whats happened to them, not been online gaming for years now.

Was the [IR] forum never deleted?

*has a quick look for Reaver forum

I haven't played for years either. Typically now that I could get a PC and internet connection that I could only dream about back then, I just don't have time to play anymore.

OKenora

The extra power is from more agressive injections and higher induction (turbo boost). Basically acellerating 40-70 in 5th gear can be done after re-map with the extra power and does use more fuel than 40-70 pre re-map in 5th would have, but pre re-map in 5th the car may/would not have acellerated from 40-70 through lack of low down power so you changed to 4th gear....40-70 in 4th will use MORE fuel than the 40-70 in 5th but with the extra power 40-70 in 5th takes near the same time as 40-70 in 4th did previously.

Presuming your driving style does not change then you will find little if any change in MPG.

As you say if it is thrashed after the re-map MPG will suffer, but if it was thrashed before the re-map then it would also suffer. The driving style is the main factor, not the re-map. If you spend most of your life with your car at the redline then yes you will notice reduced economy, show me a car that won't happen on but if you are a sensible reasonable driver who uses the engine power when he needs to rather than because he can then your MPG will be little affected if at all and can quite often increase.

You cant compare a car driven easily before re-map then driven agressively after. You have to keep the test criteria the same. Drive easy before and after, your MPG will stay steady or improve, drive agressively all the time your MPG will drop.

The weakest point in the car as always is not the car itself but the nut that connects the pedals to the steering wheel.....

Gerry

This is an interesting discussion. OKenora, but I think you are greatly exaggerating the economy gains that a remap can bring. I drive a turbocharged petrol car, and its possible that the turbo does save fuel in some cases, the car drives a lot like a turbo diesel in some ways, theres power available from 1800 revs, and loads at 2000.

If we stick with turbo diesels, and use your example of overtaking in 4th at 3500rpm, versus in 5th at 2500.
To give the same acceleration in 5th gear, the engine will need to produce more torque. This extra torque is going to need more fuel and air. More fuel and air per revolution than would be needed in 4th gear, to get the same acceleration. Its balanced out by the fact that its not spinning as fast, so its doing more work on each revolution.
Where do you see the noticeable fuel saving coming from here? Sure, it takes effort to overcome the friction in the engine, and spin it round, but is that difference in effort needed to spin it at 3500 vs 2500 going to matter when its also being asked for full power?
I think a drop in revs matters most at cruising speed, and can net you a small improvement in mpg. If the remap allows you to use 6th gear on a 6 speed box with a long 6th gear, at lower speeds than before, I can see the fuel saving there.
But for acceleration purposes, I don't think your argument holds up.

B00MSTICK

OT but what effect would chipping a car have on your insurance? Say 110 ->150 bhp as mentioned

Blitzkrieger

Phone an insurance company and ask? My insurer (Hibernian) didn't seem too bothered and didn't even raise my premium. I dunno would they all be like that.

PeteK*

Is it possible to do that re-mapping thing to a BMW 320D?

If so, what will it's BHP be afterwards?

And, does it kind od lose any power at all.. like taking off or over taking etc?

p-nut

I have been reading this thread and keeping up with it from the beginning, but after all this talk of remapping i was just wondering....is there anywhere in ireland that will do this or do you have to go to the north or uk for it??

OKenora

Engines torque does not change with the gear you are in and it's fuel consumption depends on it's revs and load not the gear you are in. higher revs = higher fuel consumption regardless of gear.

Your assumption that a non re-mapped car at 3500 revs uses less fuel than a re-mapped one at 2500 revs I beleive is wrong, i think the re-mapped one at lower revs will shade it on fuel consumption or at least be the same. I don't agree that a re-map is well suited to long top gear cruising as most cars will happily cruise in their top gear at legal speeds without a re-map. A good re-map would have little or no effect in this situation. After a re-map they will still cruise at the same speed at the same revs and with a good re-map the same fuel usage. A re-map comes into it's own for acelleration.

Re-maps are not a simple curve determining how much fuel to pump in at a specified revs. They are far more complex. They usually have a selection of different curves for differing speeds and loads so while some of these may use more fuel there will be some using less as well. There may also be more of these curves in a custom map than in the standard one meaning finer control of the engine and releasing some economy improvements. While everyone gets a re-map for "MORE POWER" they actually get far more than that when the job is done properly with improvements being made across the board to the engine mapping.

We are back to golden rule number 1 again anyway, assuming the manafacturer got it right is a mistake. A perfect example is one of the available re-maps for the Peugeot 206 S, 2.0 HDI engine (a 90bhp standard engine, same power as the 1.4 HDI). The re-map is specifically designed to improve MPG as well as adding some power, how is it done ? Peugeot intentionally mapped the engine "poorly"/conservatively to keep the power down and gain a lower insurance rating ? If they had un-leashed the full power of that engine it would make it more a hot hatch which is not what they wanted or ever had a market for. Or maybe it's as simple as the maps they used are too simple or badly developed to control the engine to its optimum ? Possible as it saves a bucket on development for them. The re-map adds about 5-7 MPG as well as releasing about 35bhp and 40 lb/ft more torque. Ask a 206 owner who has had a good re-map done for proof. This tbh is a rarer, but a not uncommon example. It's still a valid one. My main point is that driving style will affect your MPG far more than a re-map and with no change is style pre and post re-map you should usually see no decrease in MPG and quite often an increase in MPG.

My cars currently returning 47-50 mpg depending how it was driven that week, this not only exceeds the manafacturers spec but exceeds most (if not all) other cars of the same model I have ever seen or heard of which regularly claim 40-45 mpg without re-maps. It is re-mapped and not a gentle one either but was done with some consideration for economy as well as power and by a top notch company for engine tuning. The side effect is that it can be marginal for passing it's MOT on emissions (not helped by the straight through front exhaust) but hasn't failed yet, fingers crossed.

Blitzkrieger

Blitzkrieger wrote:

TBH it sounds like your car was badly tuned to being with. You just cannot get something for nothing.

OKenora wrote:

Peugeot intentionally mapped the engine "poorly"/conservatively to keep the power down and gain a lower insurance rating

So I was right then?

racso1975

ok going back on topic for one second :rolleyes:

We all seem to agree that the most important part is getting it done right....

So where can i get it done right and what should i expect to pay?

OKenora

Getting it done right has many options for places, celtictuning (Graham) and angeltuning (Nigel) both have decent reputations and despite being UK companies do regular trips to Ireland for "tuning sessions". I am sure there are many more companys that do it, but those are the 2 i have experience with and can recommend. I personally would prefer to have mine done dynamically on a rolling road, but I don't know anyone in Ireland doing that, mine was done this way in the UK, but there may be someone in Ireland doing it. Rolling road is usually far more expensive than a generic re-map.

Getting someone to come out and do the re-map for you will cost about £300(€435). I have seen quotes for less but none from a company that I know the reputation of.

If you want to do the re-map yourself then the gear you need will cost about £120 (€175) and you will also need a laptop. The re-map file will cost you between £100-120(€145-175) from most sources, though you could be brave and order a CD full of them from e-bay for about £30, but as I said you would have to be really brave. Advantage of having the gear to do it yourself is that you can easily revert back to standard when and if you need to (and you can do your m8's car too for the price of the map only).

Any re-map will also benefit from at least an induction change at the same time, consider a BMC panel filter or a BMC CDA if the budget allows. Be careful of K+N as there are strong rumours about that they leak their oil more than some other makes and can ruin your MAF.

OKenora

Might be semantics here blitzkrieger but if the car is tuned exactly as the manafacturer intended then it is not what I would call "badly tuned" though it may (will be) de-tuned from it's optimum performance to make it perfectly tuned to do what the manafacturer wants, more usually an emissions or insurance related (reduced power, lower group) issue than anything else.

If you want to say a car is badly tuned then you will have to say that all cars on the road are badly tuned from new as no manafacturer really tunes their standard road car engines for their optimum on anything performance related. The focus is more on emissions regulations these days. That applies even to the "performance" cars we see even though they may run more aggressive mapping than standard cars, for a mass produced car the map is always a compromise between emissions, economy and power. Out of those you can have usually 2 of the 3 (within reasonable limits) but not all 3 at the same time.

There are a few new cars out there that are badly tuned from new but the majority are simply not tuned for maximum power. It all depends on your target, and are you tuning for performance, economy or emissions, tuning for one may sacrifice the others but it's still not badly tuned.

Gerry

OKenora wrote:

Engines torque does not change with the gear you are in and it's fuel consumption depends on it's revs and load not the gear you are in. higher revs = higher fuel consumption regardless of gear.

If you read my post, I said that more torque is required to provide the same acceleration in a taller gear, since a gearbox is there to multiply the torque output by the engine. This extra torque presumably coming from the remap.

OKenora wrote:

Your assumption that a non re-mapped car at 3500 revs uses less fuel than a re-mapped one at 2500 revs I beleive is wrong, i think the re-mapped one at lower revs will shade it on fuel consumption or at least be the same.

I think we were talking about acceleration here. To provide the same acceleration in the taller gear, the remapped car is going to have to produce more torque. But its balanced out by the fact that its not spinning as fast. I'm repeating myself here, so I'll just say my main point was: During acceleration, differences in fuel economy from using less rev's wont' matter as much as when cruising.

The rest of your post makes sense, I'll only point out that every car is not mapped convervatively/poorly from the factory, and in many cases the gains are minimal. For naturally aspirated petrol cars, sometimes a flat spot is sorted out, but theres rarely any significant power gains. People claiming their 170bhp bmw has been chipped to 220bhp might be slightly optimistic.

OKenora

For naturally aspirated petrol cars, sometimes a flat spot is sorted out, but theres rarely any significant power gains.

Agreed, but the limit there is the air/fuel ratio not the mapping. In a n/a car you have no way to increase the airflow significantly, so can't increase the fuel flow so minimum gains from a very small bit of tweaking. If you could increase the airflow then you would see bigger gains, but then it would be a turbo or supercharged car and not a n/a . This is why re-maps are usually sold hand in hand with at least an induction change (replacement high flow filter) especially petrol re-maps. The fact that there was a flatspot is a sign of a poor map though and many cars have this. Most cars are conservative on their mapping/design with regards to maximum power output.

People claiming their 170bhp bmw has been chipped to 220bhp might be slightly optimistic.

LOL optimistic if thats what you want, downright fantasy i'd call it. A 170bhp n/a BMW can realistically expect about 15bhp max from a re-map though the car will feel like it got a lot more as a good re-map should be smoother than the original and will probably have a widened power band. A 170bhp TD car though is a different story, that can be got easily to 220 bhp or more but it's diesel bhp, which feels different to petrol bhp, it's the huge torque figures, compared to a petrol, that make the diesel feel so quick.

p-nut

OKenora wrote:

Getting it done right has many options for places, celtictuning (Graham) and angeltuning (Nigel) both have decent reputations and despite being UK companies do regular trips to Ireland for "tuning sessions". I am sure there are many more companys that do it, but those are the 2 i have experience with and can recommend. I personally would prefer to have mine done dynamically on a rolling road, but I don't know anyone in Ireland doing that, mine was done this way in the UK, but there may be someone in Ireland doing it. Rolling road is usually far more expensive than a generic re-map.

Getting someone to come out and do the re-map for you will cost about £300(€435). I have seen quotes for less but none from a company that I know the reputation of.

If you want to do the re-map yourself then the gear you need will cost about £120 (€175) and you will also need a laptop. The re-map file will cost you between £100-120(€145-175) from most sources, though you could be brave and order a CD full of them from e-bay for about £30, but as I said you would have to be really brave. Advantage of having the gear to do it yourself is that you can easily revert back to standard when and if you need to (and you can do your m8's car too for the price of the map only).

Any re-map will also benefit from at least an induction change at the same time, consider a BMC panel filter or a BMC CDA if the budget allows. Be careful of K+N as there are strong rumours about that they leak their oil more than some other makes and can ruin your MAF.

say i did opt to get all the gear to do it myself, is it difficult to carry out a full remap?