Safe Speed Forums

Just recently, I overheard a conversation in a hotel lounge in which a man was describing how he'd had his car's engine management system upgraded. The procedure consisted of a device being plugged into the onboard computer, and when the operator pressed the button, it went beep-beep-beep, and hey presto - his car had an extra ~20% power.

Apparently, this process is akin to performing a flash update to the BIOS on a PC. I've had to do a couple of those in order to unlock the hidden powers of the computer's motherboard.

A company called REVO does these upgrades. The engine management software is rewritten and installed via the engine's diagnostic port. REVO can even set it up on a 5-hour trial basis, so that the car reverts to the standard software after that period has elapsed.

But I am puzzled. Why do motor manufacturers produce engines which are deliberately detuned to deliver less performance than they could?

What are the downsides of such an upgrade? No doubt the insurance company would want to know about it. Would such an upgrade void the manufacturer's warranty? I suspect I already know the answer to that one.

Would the drive train be able to take the extra power?

What other considerations are there?

I think this is the sort of thing you mean (this is one for my car) - I have no idea how effective they are though:

http://www.partsforsaabs.com/product_in ... ts_id=2052

The flash upgrades basically alter the fuel mappings and timings set for the engine. M/Fs use very generic and conservative mappings so tuners can usually get a lot more oomph out of an engine. They'll also set it for any type of fuel so you can get more power again by setting it just for the high octane fuel. Japanese cars tend to have much more power when using the higher octane fuel as the japanese don't have the 95 ron gnat's piddle that we have here

There are some poor tuners that basically just richen the whole map so you are over fuelling. This isn't good!

If you have a turbo with electronic boost control then it is dead easy to get more power. The next limiting factor is usually the amount of fuel you can squeeze out of the fuel pump/common rail. Then you get into all sorts of complicated areas such as changing the exhaust, inlet manifold then getting bigger injectors and such like.

It's very common with FI bikes. Many bikes have a 'flat-spot' in the rev range which was put there by the manufacturer to enable the bike to more easily pass noise testing. Remapping the FI removes the flat spot.

My bike was very 'lumpy' at low revs until I remapped the fuelling. Makes for easier commuting as I now don't have to ride the clutch at 15-20mph.

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Less Kodak, more Kojak.
In times of deceit, telling the truth is a revolutionary act.

Manufacturers have lots of constraints place don them when producing a vehicle. It could be detuned to fit into a certain emissions tax band or to get a certain MPG in the standard test.



At least one company doing the remapping (not chipping) claims that the manufacturer and insurance company would not be able to tell. I find that difficult to believe.



Maybe, maybe not.

I have heard tell that some Citroen Xantias were given 110bhp HDi engines which had the crankshaft of a 90bhp engine and they all failed. If tolerances are always that close then you have to worry about reliablility.

On the other hand, people have been turning up the boost of diesel engines for a good few years now with lots of success.

The other thig to consider is that you can't get something for nothing. If you use the extra power all of the time you will use more fuel.

I'm planning on having mine done, probably early next year as I am planning a trip up Paul's way and the extra oomph in the midrange will make it much easier going on the motorways and those fantastic A roads in the Highlands.

Aye, it's a big problem! (well, I say "problem" - I suppose it depends what side of the fdence you're on!

As has been said, the manufacturer has lots of constraints that we users don't have to worry about. In Europe, they need to meet the EC type approval emissions requirements. These are infinitely tougher for a new car being "type" approved than the "in-service" limits they test to at MOT stations. During that test, they also get their official CO2 emissions figures and fuel consumption figures.

The second point is that the cars wil lbe expected to do this day-in, day-out in ANY EC Member State - regardless whether it's Southern Mediterranean heat or Scandinavian cold. They'll have to do it one pretty much ANY "pump" fuel sold anywhere in the EC (and some of it can be pretty ropey)!

The third point is that they have to give a warranty on the engine AND drivetrain. Very often, it's a drivetrain component that limits the engine output. They need to consider that the car might be towing the heaviest trailer it is authorised to tow in the worst conditions forseeable, every day of it's warranty period.

So, what with one thing and another, they do tend to play it safe. It is true, however, that they use the "chipping" tactic themselves increasingly these days, with a "go-faster" version of a particular car only really differeing in its fuel map.

Also, as has been said, a cheap "chip" (or flash) can do more harm than good as the extra fuel can wash oil off the cylinder walls in extreme cases and trash the engine over a period of time. Normally aspirated cars are much harder to get more power out of in this way but turbo cars are dead easy - depending on how long you want your engine to last - just whak the boost up!

FInally, I don't believe it would be very difficult to tell. In most minor prangs, it wouldn't be worth bothering with but if there was a big insurance claim at stake, I'd have thought it would be pretty easy to pull the ECU out of the car and post it to the manufacturer who could compare the "map" in it with the standard one!

Actually I'm dead worried about aftermarket 'chipping'.

Did the chip tuner check:

- Engine longevity?
- At altitude?
- At extremes of heat and cold?
- For problems with long high speed / high load runs?
- with extremes of fuel specification?

No they bloody didn't. But the manufacturer did, and with a few exceptions, the manufacturer tuned the engine for the higest possible output consistant with reliable operations.

The exceptions are where a manufacturer has used 'chip detuning' to distinguish lower spec models.

I wouldn't DREAM of chipping a car I cared about.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

I've wondered about this for a while, not the aftermarket jobs but the manufacturers.

I drive the motoring equivalent of sensible brown lace ups - a 1.9 Diesel Passat. It's the 130 PS TDi version. For a grand or so less, I could have had the 100 PS version. Same engine, same car, but 23% less power.

Previously, I believe the same variants were sold as 110 and 90 PS respectively.

There were, as far as I know, no engine components changed between the 110 and 130 variants, it was an ECU change. Also, as far as I have been able to ascertain, the difference between the 100 and 130 PS variants is wholly ECU related. Go figure.

On the other hand, my wife's bus has a 2.9 CRDi engine which puts out 140 PS. The new version uses "mostly" the same engine but puts out 180 PS, and the new car is a bit lighter too. I can't imagine a 40 PS upgrade is wholly ECU related in this case, but then without getting access to a pair of engines and time to compare, I guess I'll never find out.

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COAST Not just somewhere to keep a beach.

A young loner on a crusade to champion the cause of the innocent, the helpless, the powerless, in a world of criminals who operate above the law.

My car has been "chipped" (remapped actually as the chip was flashed rather than replaced), but with the qualification that the mod was developed by a specialist company with intimate knowledge of the vehicle and its manufactured limits, went through comprehensive testing, is fully manufacturer approved, dealer fitted and doesn't invalidate the warranty. Available as an option when the car is bought or as a later aftermarket fit, it is packaged with some airflow improvements (like a completely new and much larger diameter exhaust) and the combination adds about 25% tourque across the complete rev range. Oh and it can go a bit too.

It is necessary to inform the insurers of the modification otherwise you do not have insurance; it is up to the insurers to decide if this will cost you more in premiums or not - some will not touch you and are confused by the whole idea, others say it makes no difference. In my case, the exhaust ending in a single 4" pipe rather than a pair of 1.5" pipes is a big giveaway should the car be involved in an accident. The claim inspectors are likely to be able to spot such subtle signs.

I guess the reason for the manufacturer not doing it himself in your case is down to emissions / noise performance in the type approval tests. A number of manufacturer's do this with their "go-faster" bits. They make them a "dealer-fitted option". These ought to be fitted once the vehicle is registered because that way, the Type Approval requirements are no longer important. It only has to met "in-service" requirements which are much less stringent!

I think, Paul, it's not completely fair to tar all chip tuners wit hthe same brush. There are a few out there who really do know what they're doing and have enough faith in their products to underwrite the manufacturer's warranty...

...and then there's the £30 chip I bought on Ebay...!

Seems to work so far though! Not much extra power. Maybe a little bit in the mid-range but the car is a fair bit thirstier!

Wow, you got a good one.

I have not heard of a sub £300 chip which actually worked. Remaps at around £200 bt anything a lot cheaper is generally snakeoil.

My IT office is sublet from a tuner who dyno tunes every car individually. He starts with a basic modified map and then fine tunes it to suit the car.

The customer is made well aware that the tune is based on the current fuel and the car is tuned to achieve optimum performance from it. If the customer fills up with a lower quality fuel the engine may be damaged from detonation.

For a genuine high performance junkie there is no better way to get more power for low cost.

Their individual tune is saved and if the car is still under warranty they return the car to the factory tune prior to having it serviced and then back to the high performance tune later. This is a five minute process and there is absolutely no way the manufacturers can tell.

The easiest cars to get large increases from are turbo or supercharged engines as enormous gains can be made from increasing the boost by even small increments and mapping the fuel to suit. In modern cars the maximum boost is controlled by the ECU so there is no need to change any hardware under the bonnet.

Wilder tunes, like on my car, require big changes under the bonnet. My Subaru develops 235kw atw but to achieve this I increased capacity to 2.5l and increased the injector size and fuel pump size to allow sufficient fuel on full power loads. On full throttle you can almost see the fuel gauge dropping but under light loads it is still fairly economical.

I 'chipped' my BMW E34 535 and E34 M5 without any problems, even after a years usage and I know of lots of enthusiast who have tuned their cars without long term side effects.

Horses for courses - if you want more power without paying a fortune and your car supports a manual tune of the computer I would highly recommend it provided you shop around and find someone who genuinely knows what they are doing.

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Ross

Yes I'm a hoon, but only on the track!!!!

These actions may crinimally defraud a manufacturer if warranty work is required.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Not necessarily! Some (?most?) of the cheap chips are indeed "snake oil" and some of the worst will make it run so rich that the engine gets damaged but I strongly suspect a lot of the other cheap chippers are just "honest" cowboys making a living by copying a "proper" chip that has been carefully developed!

There is a lot of this done in agriculture to engines. We had a new combine two years ago. The 7.5 litre engine was (Cat 3126) was struggling with the load. This engine was rated at 310hp and versions of it are up to 500hp. They manufacturer came out to the machine armed with a lap top to see if the engine was perfroming to spec. it was. We asked them for more power, baring in mind it had plenty of spare capacity. NO! was the response. You won't keep it cool in this application and we won't warranty it. The machine had to go and the new one has a Cat C10 at 362hp driving the same machine and still huffs and puffs.

All of the tractors that I have come across that have had trasmission failures have had the fuel turned up by the operator (should be sacking offence). If the maunfacture had ment the drive train to handle 180hp, they wouldn't have supplied a 120 hp engine.

Interesting - suspect Adam L 's box was a one size fits all engine with expensive gearbox mods.(basic model ---120bhp with 180bhp box - mod engine , add stronger gearbox bits ---ad infinitum, oh and price went up accordingly)
On another tack , some years ago, i found a cheap way of getting more power out of a 2.0L vauxhall engine - fit a resistor in the line from the air intake sensor --problem was that as power went up , fuel consumption did likewise.

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

There's generally two types of reflash out there.

There is the remap which has already been described. It's done on a dyno or on a test track (or sometimes on the public road!) and will be the optimum map for that car's current fuel and current modifications if any. A lot of Subaru owners go down this route since the UK car is seriously detuned from the Japanese version, and the Japanese version is itself detuned in order to meet the 280bhp "gentlemans agreement" that car manufacturers have over there.

In some ways a mapped engine is better than the stock map, it will be more efficient, have lower emissions and will have more power. You can also get it mapped to your own driving preferences, with the engine optimised for low end grunt rather than being a top-end dyno queen if that if your preference. It also means you will get the full benefit of any modifications you have made. The downside is that if the conditions change, if you find yourself stuck on a near empty tank and the only garage for miles around is a Murco, you will likely damage your engine. It is of course possible to have your mapper do a conservative map and some of the upgrades allow for map switching to get you out of this situation. You ca have a 99RON map and a 95RON map. You can have an MOT map and a track map. One thing a lot of people miss is that with a custom map you really want to be getting it redone every year since the engine will wear and its characteristics will change.


The other option is the "chip" option, where a company has produced an improved map for the stock engine, and for the engine in various states of tune. This is where you get all the Stage 1, Stage 2 etc. coming in. For example if you are going to get a Horsham Developments chip for a Nissan 200SX. Stage 1 is basically stock. Stage 2 is a map for a car with a big exhaust, T28 turbo and a front mount intercooler. Stage 3 is bigger injectors and some other stuff. The map is a bit more conservative than a custom map for your car, but if it's from a reputable company then a lot more people will have tested your map, which is good.


Lastly, as Paul mentions there is the chip which is used when a company offer the same engine with different levels of performance. The VW Golf diesels are a classic example of this, the same engine is available in 90bhp - 140bhp variants which are basically software. It's currently popular amongst company car drivers to get the lowst spec with the lowest emissions, pay tax on that and then chip it to a higher spec and this is totally legal as long as insurance are informed. People have gotten that 1.9 diesel engine up to 350hp on stock internals so I'm prettu sure that any sane map would be ok.


Which reminds me, I really need to get my Legacy remapped as it's still configured for 100RON and not the 97RON gnats piss we get over here

dubious at best.

if you don't trust the manufacturer to give you the most bang for your buck.... buy something else.

Apart from the technical issues about wide temperature range, fuel quality etc. manufacturers have also to preserve range integrity from model to model. They thus don't give you the best "bang for the buck".

For example, the 3.0L diesel X5 can easily and reliably be modified to give 260bhp and 600NM torque which makes it as fast as the 4.4L V8 petrol model - which costs £15K more. BMW are not going to sell you this, however.

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Malcolm W.
The views expressed in this post are personal opinions and do not represent the views of Safespeed.

Why? None of them do. They set it up for a balance of longevity, power, emissions and so on. The ultimate example is F1 cars. upwards of 700bhp from a 1.5 litre naturally aspirated engine, unfortunately they only last a few hours because that's all you need. At the other end of the scale, Is the VW SDI engine, a paltry 64bhp from a 1.9 litre diesel that could easilly be capable of more with a few alterations and a flash, but that SDI will probably still be running when I am old and grey despite a lifetime of thrashing by white van men.

If your car is going to be a track car only then the manufacturers defaults are not meaningful for you, you dont care if your chip means the engine will only last 20,000 miles because you're only doing a few thousand a year, wheras for normal people that means the engine would blow up within the waranty period which obviously the manufacturers dont want.

Anpother classic example is the Mitsubishi Evo. 280bhp in standard form, and 280bhp is the only one you get in Japan. (all Evos prior to the evo8 are grey imports) The evo was a rally homologation special and do you honestly think that the rally version was restricted to 280bhp. It wasnt. You can safely chip it to higher figures. In fact on the Evo8 Mitsubishi will do this for you, and slap a badge on the back saying FQ-400. All the FQ range of Evos are flashed after registration to get around emissions regulations.

On other cars the situation is a little different. I am aware of somebody who had their Sierra Cosworth chipped for an extra 100bhp. The engine can take it just fine but the gearbox couldn't so that had to be uprated to match. The owner didn't care though and just took it as part of the cost of owning a modified car, he'd planned from the start to save for a new gearbox and hopefully have enough by the time it finally grenaded itself.

Ultimately it's just a more advanced form of old fashioned tuning. Do you only ever run on 98RON, great, advance the timing a bit and chuck a decent Weber carb on to get more fuel in. The result is the same, only not as carefully managed