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(Post Link) post #1 of 45 Old 04-02-09 Thread Starter
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Some of the basics of re-mapping(to be updated)

What is re-mapping?

Re-mapping is referred to software changes in the engine mangement control unit usually called ECU.

The ECU is collecting data from the different sensors several thousand times a second. This data is then processed and referenced to the different mapping tables in order to get for the load on the engine at the relevant rpm the right ignition timing and amount of fuel each cycle.

This data depends on a variety of conditions, which include climatic conditions, fuel quality (as well as mixing different brands of fuels in any ration) and homologation requirements.

As the map is written to make the particular ECU drivable under all the conditions that we might face on the planet.

Homologation is one of the worse contributors to the lack of power in a map.

When changing the map (re-mapping or chipping or piggy backing) it is optimised for the standard car. This re-map needs further altering when modifications are done in order to get the optimal performance out of the engine.

When it is referred to a generic re-map we usually talking about a re-map that has been done on one car of the same spec and is carried over to any car of this spec when uploading it to the relevant ECU. These generic maps in most of the cases show an improvement, but can sometimes be of little or no effect depending on the production tolerances. This is why it is advisable to go and do it on the rolling road (I personally would never let anyone come to my door and upload a map this way).

Whether piggy backing, chipping or re-mapping the basic idea is the same.

Some ECUs can't be written to, which means that they either need a stand alone replacement, which is the best but most expensive option in this case or a pigg back. The latter ones usually proove to be rather inefficient and far too costly for the result.

Some ECUs can be chipped, which means that the chip is taken out and replaced or overwritten. Whether it is taken out or overwritten in the ECU does not make a difference to the re-mapping.

Some ECUs can't be chipped because it is virtually impossibly to remove the chip, which can be for different reasons (i.e. gel pack ECU will loose the gel and will be physically destroyed).

Re-mapping is being referred to when the sofware is being loaded up without taking the chip out.

Re-mapping and chipping are essential the same. In both the mapping tables are optimised for improved performance. The mapping tables are an improvement reference data in order to increas/optimise performance.

The difference between a generic map and a custom map is that the custom map is done by evaluating the individual engine rather than the engine type. When optimum performance is required this is necessary becauseof production tolerances. Someof the door step mappers insist thatthe ECU will adapt, but this is not completely correct.

All modifications to gain performance have one single purpose, which is to draw as much air in as possible. Once achieved it is not only important to get more fuel in, but also to correct the ignition timing, which is an important part of the lengthy custom re-mapping.

A custom re-mapis not necessarily alive re-map. In most of the cases a live re-map on non chipable ECUs is only possible with a special type of hardware, which very few people own.

The advantage of alive re-map is that because it ispossible to simulate the ECU on a laptop that each mapping point can be altered at the same time when tested and the results can be instantly monitored while making the changes.

The same results can be achieved with a non live re-map but will take many times the amount of time and is very impractible to achieve.
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Re: Some of the basics of re-mapping(to be updated)

CPH can you empty your pm box please
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Re: Some of the basics of re-mapping(to be updated)

Cheers Pete,

can you go into areas that are changed, and why they are changed, such as fuel pressure rail, boost pressure, throttle position, torque limiters, etc etc.

I watched over Oggies shoulder the other day quizzing him on what was what (probably got sick of me doing so), it was intersting seeing how he dealt with the torque limiter to level out the power/torque line.

My interest is in the EDC15 as I have 2 JTD's with this fitted.
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Re: Some of the basics of re-mapping(to be updated)

This is going to be an interesting one to keep an eye on. Nice one!
 
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Re: Some of the basics of re-mapping(to be updated)

Perhaps make a sticky???
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Re: Some of the basics of re-mapping(to be updated)

Hi Pete (CPH)

You don't fancy taking my car away with you next week when you drop off my GRS silicone hose so you can work your magic ?


It's just I have booked my car in with Angel Tuning (Only have read good things and they are the closest to me) and after reading some of these posts regarding remaps I find myself uncomfortable.
Can someone put my mind at rest?
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Re: Some of the basics of re-mapping(to be updated)

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Originally Posted by GhostyDog View Post
Hope it doesn't turn into a willy waving contest, there's some damn fine information sitting in peoples heads that could be digested by the community.

Unfortunately though the information given here is to say the least inaccurate,is not acceptable even as a layman's understanding of the subject.
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Re: Some of the basics of re-mapping(to be updated)

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Originally Posted by The Big Dog View Post
It's just I have booked my car in with Angel Tuning (Only have read good things and they are the closest to me) and after reading some of these posts regarding remaps I find myself uncomfortable.
Can someone put my mind at rest?
I think you'd be best getting the car rolling road tuned or even better find a tuner who can do a combination of rolling road and open road, it's all good and well tuning the engine on a rolling road for peak power but if you lose driveability is there any point?

Everybodies car wears diferently because not many peopl have the same driving style, especially people who are interested in performance tuning.

It's not just about the engine after all, there are roads where I live that anybody in a 1 litre fiesta could keep up with me on because the roads are beyond the cars ability to go any faster.safely.
Just me tuppence.

Nero Fuoco 147 Lusso - Bianco Nuvola 147 GTA - Carbonio Brera SV - Azzurro Le Mans GT 1600 Junior
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Re: Some of the basics of re-mapping(to be updated)

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Originally Posted by The Big Dog View Post
Hi Pete (CPH)

You don't fancy taking my car away with you next week when you drop off my GRS silicone hose so you can work your magic ?


It's just I have booked my car in with Angel Tuning (Only have read good things and they are the closest to me) and after reading some of these posts regarding remaps I find myself uncomfortable.
Can someone put my mind at rest?
There are lots of happy people running Angel's maps on here, myself included. Yet to hear of an engine going pop because of any map from the reputable, tried and tested mappers here and if any company treats the customers badly then they won't last long on here.

They do a 30 day (or something like that) money back guarantee. My map brought back an old turbo overboost problem and they came back and adjusted the map, no hassles. So if it all goes wrong on you, they're good blokes and will come and re-do it or take it off for you.
 
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Re: Some of the basics of re-mapping(to be updated)

I think what we all want is the correct information so we can understand better whats going on with our cars. We are discussing technical issues where wrong information will or could damage your cars.
So all I am saying is let the professionals have there say (even if you dont like what they are saying), and take in the information. If you are unsure just ring them. They will only be too glad to help and explain I suspect.

Please no more of I will get you banned ect. That is not constructed or helpful.

Sorry if you feel I am having a dig or winge, but like most people here I want to learn and understand.


Peace to all people.
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Re: Some of the basics of re-mapping(to be updated)

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Originally Posted by jasons View Post
can you go into areas that are changed, and why they are changed, such as fuel pressure rail, boost pressure, throttle position, torque limiters, etc etc.
I would have thought the big ones would be:

Fuel Mixture: This is the ratio of air and petrol that gets injected into the engine for it to burn to make power. In a perfect world, this could be done based on pure physics as you would look at the chemical formula for the combustion to determine precisly the right amount of petrol for the amount of air. If you got this spot on you would burn all the air (or oxygen more to the point) and all the petrol. This would be called a stoichiometric equation / combustion. For petrol, this occures at about 14.7 to 1 (air to petrol mix).

The world is rarely perfect however so you generally have a choice to make, do you want to burn all the petrol or all the oxygen? Now, if maxiumun efficiency is your goal, you'll want to burn all that petrol. This will also lead to lower emissions. The best way to do that is to inject slightly less than an optimum amount of petrol, that way there is plenty of oxygen to go around and you can be sure you won't be wasting any petrol. If this gets taken to the extreme you get what are sometimes refered to as 'lean burn' engines which design solely to operate under such conditions to return maximum MPG. Forgetting that though, this is generally where manufacturers will aim to setup a std car.

However. If power is your quest then what you really need to be doing is maximising the amount of oxygen or air that you are burning, not really the petrol. It's how much oxygen you burn that really equates to power, that is why 90% of tuning modifications focus on getting more oxygen into the engine. So in this case, we need to inject slightly more fuel than neccessary in order to make sure we maximise the amount of oxygen burnt and power generated.

Now these lines are quite fine these days because engines are so efficient. An old car that was less efficient would probably deliver max power at around 12:1, but I guess 13:1 is closer the mark now. So by making adjustments here, it is easy to gain power, but it is likely to come at the expense of MPG (or at least it should if the std Map is any good).

Ignition Timing: This goes hand in hand with the fuel mixture. For any given fuel mixture, engine load and RPM, there will be an optium ignition timing. This is essentially when the spark plug fires in relation to the engine cycle (i.e. where the pistons / crank shaft are). Now getting this right is tough because you're talking fine tuning and it is probably where a rolling road tune is required. Again though you're essentially looking to adjust the timing to where it is most efficient for the engine and conditions. Generally, this will be advanced (which mean the spark plug fires earlier in the sequence and gets the fuel burning earlier) as it tends to create more power; but the more you advance the timing the more you risk the fuel igniting too early. To describe this in simple terms, too early means the combustion will try to force the piston back around the engine the wrong way. In practice it wont do that, it'll just get real hot and melt everything. Do to that 'risk', std maps are likely to be quite 'conservative' on their ignition timing so again there are gains to be had by advancing this a little and still be in safe margins.


Things like increased fuel pressure can improve throttle response but won't really increase power. Upping the rev limit is worthwhile as this is quite low as std (6800RPM on a V6 say) when in reality, 7200RPM will allow you to use a little more top end 'gas'!

The world get's different with turbo's because if you can control the boost then you can start to generate serious power, which is why you see such high gains for JTD's etc.

Hope that's a start.
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Re: Some of the basics of re-mapping(to be updated)

Good post ChrisH.
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Re: Some of the basics of re-mapping(to be updated)

Nice one! Excellent post there Chris
 
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Re: Some of the basics of re-mapping(to be updated)

Well CPH I have to say you started the slagging match on the other thread
We as tuners are just trying to make people a where of
crap remaps and some so called custom maps cheap or expensive
that are damaging the chip tuning business

We havenít ever said what companies are at fault
But trust me some of the files I have seen in here
are shocking

Some people get more power then others that dose not make a bad
map .and just because some people clam more power then others
that also doesnít necessarily make it a good file

Alfa Tuner has been making files for over 20 years and is one of the best in the
business.
Reading your remapping thread I have to say I agree its way off
Sounds like you have some experience with standalone ecus
But not much with OE
I donít think you should be threatening people its out of order
You have just been told your post is inaccurate on some points
Well most pointís really.
Why not just have a discussion about it

Iíve been building race engines and mapping ecus for around 15 years
I donít know it all and will never stop learning in this game .
Modifying files in OE ecus can not be done live on a lot of new ecus the word
you are looking for in your post is an Emulator.
This involves unsoldering the EPROM fitting an a socket etc .
Try doing that on a 7.3 or 5.5 etc etc
True chip tuners have to do more then just plug a lead in up load a modified
files that they got from the Internet.
We have to open ecus on some,read the file in boot mode or bdm
modify the files and correct the check sums etc etc etc

Get cars In test files etc etc
This is why we can not carry out a remap and a induction kit for
inc rolling road etc for £250

OBD tuning is quite a new thing
You will find a lot of so called tuners will not take on say
156 2.5& 3.0LGTV with early ecu s ME 2.1 2.2 3.2 JTS, Petrol Mitos etc as they are
not a straight forward obd job and take to long
and in most cases they couldnít do it any way

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Re: Some of the basics of re-mapping(to be updated)

If the information is not entirely accurate, would it not be better to input your expertese and write something that is correct?

You could start with a couple of typical examples...

1. alfa jtd with induction and fmic - as this seems to be buzzing around other posts - lets hear what you would do.

2. ala v6, with gta/other cams, intake and exhaust - interested to see hear what you say about rev limiter, would you raise it, if so to what?

3. alfa TS, exhaust and intake.
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Re: Some of the basics of re-mapping(to be updated)

Quote:
Originally Posted by AHM View Post
CPH Quote
And just to show how helpful Alfa Tuner wants to be on the subject: It is nearly an hour that he could have come on and corrected my rubbish and he hasn't done it despite being online.


I expect heís got work to do like most of us and left his pc on line :
I do not take kindly to threats or insults (and this is the second different thread that CPH has insulted me)and because i dont want this to escalate in a public forum i am not going to say anything else on the matter.
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(Post Link) post #17 of 45 Old 05-02-09 Thread Starter
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Re: Some of the basics of re-mapping(to be updated)

Quote:
Originally Posted by AHM View Post
Well CPH I have to say you started the slagging match on the other thread
We as tuners are just trying to make people a where of
crap remaps and some so called custom maps cheap or expensive
that are damaging the chip tuning business

We havenít ever said what companies are at fault
But trust me some of the files I have seen in here
are shocking

Some people get more power then others that dose not make a bad
map .and just because some people clam more power then others
that also doesnít necessarily make it a good file

Alfa Tuner has been making files for over 20 years and is one of the best in the
business.
Reading your remapping thread I have to say I agree its way off
Sounds like you have some experience with standalone ecus
But not much with OE
I donít think you should be threatening people its out of order
You have just been told your post is inaccurate on some points
Well most pointís really.
Why not just have a discussion about it

Iíve been building race engines and mapping ecus for around 15 years
I donít know it all and will never stop learning in this game .
Modifying files in OE ecus can not be done live on a lot of new ecus the word
you are looking for in your post is an Emulator.
This involves unsoldering the EPROM fitting an a socket etc .
Try doing that on a 7.3 or 5.5 etc etc
True chip tuners have to do more then just plug a lead in up load a modified
files that they got from the Internet.
We have to open ecus on some,read the file in boot mode or bdm
modify the files and correct the check sums etc etc etc

Get cars In test files etc etc
This is why we can not carry out a remap and a induction kit for
inc rolling road etc for £250

OBD tuning is quite a new thing
You will find a lot of so called tuners will not take on say
156 2.5& 3.0LGTV with early ecu s ME 2.1 2.2 3.2 JTS, Petrol Mitos etc as they are
not a straight forward obd job and take to long
and in most cases they couldnít do it any way

I have not started the slagging match. It was started by someone else.

It is very unprofessional to call someone a 7 year old.

As you probably have read in the title it says : Some of the basics.

There is quite a bit more involved.

Regarding the emulator: No, I did not refer to the emulator. I know what an emulator is.

I know what the BDM is and I know a lot more about ECUs.

Rather than trying to read anything into the information I gave it would help to re-write it that it casn be useful.

I have at no point claimed that a lower power map is inferior to any other. You actually imply I made accusations, when they do come out of your writing against me.

I do know very well how many so called tuners are selling crap. I have seen plenty of maps I would not want to have on my cars.

Whether Alfa Tuner is one of the best or not on the re-mapping side does not mean that he needs to have an arrogant attitude.

Having been a consultant on the development side in the automotive industries the first people I sack are the ones that tell me I am wrong without trying to correct things.

You Adie and Alfa Tuner do not read properly. If you had done so you would have not responded with this post.

I am open to criticism, but only when it is constructive

You failed to show me where I am wrong.

I doubt that you can show me where I am wrong because you don't even understand what I was referring to - most likely you don't read uit properly.

There is much more info needed and needs to be much more detailed.

Your offer to discuss it I can't take serious at this moment in time as you just attack and not discuss.

I only can say hats off to ChrisH. He has taken the opportunity to add something useful.

What about if you start doing the same?
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Re: Some of the basics of re-mapping(to be updated)

Quote:
Originally Posted by CPH View Post
I only can say hats off to ChrisH. He has taken the opportunity to add something useful.
+1

I found his post interesting and informative (including the original post by CPH btw).



I sense some serious 'willy waving' (as GD so wonderfully put) going on...

This thing about allowing people to advertise their own co seems to be creating some 'interesting' clashes right now.

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Re: Some of the basics of re-mapping(to be updated)

ChrisH, your post is awesome, I knew compression ratios existed and altering them was a key to bigger power but before reading your post I could never quite get it to click how it worked in my head.

In reading your post it just clicked and now I can go back and re read some of those old threads talking about CR and understand a bit more the physics involved.

Quality

I agree with what Jasons said, what would benefit this thread best would be some practical examples, the theory is nice as well but in practise what can be done?

Ta

Sean
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Re: Some of the basics of re-mapping(to be updated)

Quote:
Originally Posted by CPH View Post
Sorry but I have to withdraw further assistance to the re-mapping threads and can't fulfill my promise to write more about it as it is considered an insult to other members as I just was told by pm. Otherwise I might get banned.

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Re: Some of the basics of re-mapping(to be updated)

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Sorry but I have to withdraw further assistance to the re-mapping threads and can't fulfill my promise to write more about it as it is considered an insult to other members as I just was told by pm. Otherwise I might get banned.
Now that is a shame.

Quote:
Originally Posted by Dibby in another thread
every time a remapping thread comes up we get a willy-waving contest of my mapper's better than your mapper
Good old Alfaowner.com atmosphere strikes again and puts an end to something that could have been so informative and useful. FFS!
 
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Re: Some of the basics of re-mapping(to be updated)

Truth hurts!
Must of touched a nerve
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Re: Some of the basics of re-mapping(to be updated)

Now this is a real shame.

The only thing to have come out of this is a distinguishment between those who shout big things and those who actually post usefull information that is both helpfull and of interest to others.

A thumbs up to ChrisH and CPH who have proved by their posts that they have constuctive and informative information to offer - and more importantly - they have done so.
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Re: Some of the basics of re-mapping(to be updated)

Thanks for the thanks guys! Glad it is of use, I'll try to add some more over the next few days...

...and I'll start with compression ratios:

Quote:
Originally Posted by GhostyDog View Post
ChrisH, your post is awesome, I knew compression ratios existed and altering them was a key to bigger power but before reading your post I could never quite get it to click how it worked in my head.
A little confusion here to start. The ratios I was refering to above was the Fuel mixture, so that's the ratio of petrol to oxygen that is present in the engine. The air gets sucked in through the air filter, the petrol gets squirted in by the injectors. It is key, for the reasons above, that the ratio or percentage of each is correct to get good results.

Compression ratio is different again. This refers to the amount the fuel mixture is compressed by the pistons. So, quick bit of engine theory. A four stroke engine rotates twice for each 'firing' cycle (i.e. the pistons go up and down twice but the spark plug only fires once. The first down cycle draws in the fuel, it sucks it in as the piston goes down (think of a surringe being drawn out). It then goes back up but now the valves are closed and this compresses the fuel mixture. This is important as it won't combust (explode) properly unless this is done. It then fires the spark plug and bang, the mixture explodes forcing the piston back down. On it's way back up for the second time the exhaust port opens to get rid of the gas and hey presto we start again.

So, the important bit. The compressing of the fuel. The compression ratio essentially refers to how much the fuel gets compressed. So if you think about the amount of space in the cylinder when the piston is at the bottom, it is far more than when the piston is at the top, hence, when the piston travels up it compresses the fuel. The difference between these two volumes is known as the compression ratio.

Compression Rations (or CR's) are key both to producing power and fuel economy. They are one of the only areas where a tuning increase produces both more power and more MPG, generally, you can regard those things as mutually exclusive (real general dont bite me on that one). Basically, the higher the CR the easier and more violently the mixture will explode. This means two things, A, more power, B, more efficient creation of power for a given amount of fuel. This is why it improves both power and MPG.

An optimum CR for petrol tends to be about 11:1. Basically you want this as high as possible without causing an un-controlled explosion. The problem is, the more you compress fule, the more volotile it becomes until eventually it will combust of its own accord (i.e. before the spark plug fires). If this happens you loose control of your ignition timing (it in effects becomes irelevant) and therefore you are likely to get what is called pre-ignition (or pinking / detonation). Same as I said before, it means the mixture will explode too early and try to force the piston the wrong way back down hence melting your engine.

Now on old cars raising the CR was an easy way to make power. As std they may have been as low as 8:1 so there was loads of potential gain there. Nowadays, not really the case. Because of the benefits to MPG as well, most manufacturers produce vehicles with pretty high CR's right out the factory. In order to raise the CR you need to remove the cylinder heads, work out the volume of the combustion chambers, work out the piston bore and stoke, even things like the thickness of the head gasket, then skim the head accordingly. Quite a bit of maths and work to get it right. When you're jumping from 8:1 to 10.5:1, that is worth it, to go from 10.5:1 to 11:1, probably not worth it unless you have the heads of for a rebuild.

Some other points to throw in... the more you can stabalise the mixture the higher a CR you can run. The best way to do this is run premium fuel - the higher the octaine rating, the more stable it will be. You can also keep the intake temperature as cool as possible.

So finnally, why do people talk about lowering CR for forced induction applications? Because then you are compressing, already compressed air (i.e. the turbo/supercharger has already compressed it then your engine compresses it again). The combined result of this at an 11:1 CR would be simply too much, que melting of engine, hence, it is often neccessary to lower the CR if you are to run big boost numbers using forced induction. Generally, turbo charged engine will run between 6:1 and 8:1 for this reason.

Hope that helps... its a bit more technical than simple fueling I guess...
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Re: Some of the basics of re-mapping(to be updated)

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Thanks for the thanks guys! Glad it is of use, I'll try to add some more over the next few days...

...and I'll start with compression ratios:



A little confusion here to start. The ratios I was refering to above was the Fuel mixture, so that's the ratio of petrol to oxygen that is present in the engine. The air gets sucked in through the air filter, the petrol gets squirted in by the injectors. It is key, for the reasons above, that the ratio or percentage of each is correct to get good results.

Compression ratio is different again. This refers to the amount the fuel mixture is compressed by the pistons. So, quick bit of engine theory. A four stroke engine rotates twice for each 'firing' cycle (i.e. the pistons go up and down twice but the spark plug only fires once. The first down cycle draws in the fuel, it sucks it in as the piston goes down (think of a surringe being drawn out). It then goes back up but now the valves are closed and this compresses the fuel mixture. This is important as it won't combust (explode) properly unless this is done. It then fires the spark plug and bang, the mixture explodes forcing the piston back down. On it's way back up for the second time the exhaust port opens to get rid of the gas and hey presto we start again.

So, the important bit. The compressing of the fuel. The compression ratio essentially refers to how much the fuel gets compressed. So if you think about the amount of space in the cylinder when the piston is at the bottom, it is far more than when the piston is at the top, hence, when the piston travels up it compresses the fuel. The difference between these two volumes is known as the compression ratio.

Compression Rations (or CR's) are key both to producing power and fuel economy. They are one of the only areas where a tuning increase produces both more power and more MPG, generally, you can regard those things as mutually exclusive (real general dont bite me on that one). Basically, the higher the CR the easier and more violently the mixture will explode. This means two things, A, more power, B, more efficient creation of power for a given amount of fuel. This is why it improves both power and MPG.

An optimum CR for petrol tends to be about 11:1. Basically you want this as high as possible without causing an un-controlled explosion. The problem is, the more you compress fule, the more volotile it becomes until eventually it will combust of its own accord (i.e. before the spark plug fires). If this happens you loose control of your ignition timing (it in effects becomes irelevant) and therefore you are likely to get what is called pre-ignition (or pinking / detonation). Same as I said before, it means the mixture will explode too early and try to force the piston the wrong way back down hence melting your engine.

Now on old cars raising the CR was an easy way to make power. As std they may have been as low as 8:1 so there was loads of potential gain there. Nowadays, not really the case. Because of the benefits to MPG as well, most manufacturers produce vehicles with pretty high CR's right out the factory. In order to raise the CR you need to remove the cylinder heads, work out the volume of the combustion chambers, work out the piston bore and stoke, even things like the thickness of the head gasket, then skim the head accordingly. Quite a bit of maths and work to get it right. When you're jumping from 8:1 to 10.5:1, that is worth it, to go from 10.5:1 to 11:1, probably not worth it unless you have the heads of for a rebuild.

Some other points to throw in... the more you can stabalise the mixture the higher a CR you can run. The best way to do this is run premium fuel - the higher the octaine rating, the more stable it will be. You can also keep the intake temperature as cool as possible.

So finnally, why do people talk about lowering CR for forced induction applications? Because then you are compressing, already compressed air (i.e. the turbo/supercharger has already compressed it then your engine compresses it again). The combined result of this at an 11:1 CR would be simply too much, que melting of engine, hence, it is often neccessary to lower the CR if you are to run big boost numbers using forced induction. Generally, turbo charged engine will run between 6:1 and 8:1 for this reason.

Hope that helps... its a bit more technical than simple fueling I guess...

Sorry guys am I daft or is anybody else trying to follow this.
I have been following another thread to make my mind up what I should do if I buy a 147JTD I am now baffled.
ChrisH do you remap etc and if so can you help. I am trying to get feed back. As said in a previous post I think I have got it whittled down to a couple of companies.

Harry
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