Chipping for dummies
09-01-1999, 09:37 AM
#2
Guest
Posts: n/a
Re: here you go
Here is a repost from the now infamous series of posts from Alan Adamson. It gets a bit technical but explains a lot about the function of a perfromance chip...
__________________________________________________ ________
Ok, let's talk about chips. Actually, more technically, let's talk about the instruction code and tables that the processor in the ECU uses to control the engine. These instructions and tables are stored in a programmable, non-volitale memory called a Flash Eprom. In the A4, Bosch uses an AMD 29f200B flash part. It's physically soldered down to the main ECU board in whats called a PSOP package. Basically a 44 pin part with little,
.050 spacing, gull wing looking pins that are soldered down.
Inside this part are both processor instructions and lookup tables for various functions. To name a few, boost, timing, fuel, RPM, idle, rev limiter, speed limiter, etc.
Ok, so that's the technical description of the parts. One other note, a flash part can be read and programmed. Obviously it can be read because the processor needs to get instuctions to execute and look at the tables as is needed. One other comment, there is RAM inside the processor or perhaps external, but either way, the little processor does just like a PC, when it's first turned on it boots (actually the lower section of the flash
part has a protected boot partition just like the boot sector on a HD), and starts running it's program which in this case controls the engine. Part of that bootup process may include downloading or loading from ROM to RAM a baseline table to be used for the various fuctions.
This table may be "tweaked" as the ECU "learns" both how you drive and the conditions the engine is running in. In NO way does the processor write this "learned" table back to the flash part. It's stored in another non-volitale RAM area and used and tweaked as needed. Usually removing the power to the ECU will clear the "learned" instructions and cause a reload of the "baseline" tables, but not under all circumstances. We won't
go there for this dicsussion.
Because a flash part can be read, a chip tuner will take an 'image' of a particular rev of code, by removing the part from the board and reading it with an eprom programmer, and modify the tables inside to produce better performance. In no cases, that I'm aware of, do they modify the instruction code in the flash, just simply the tables.
In the A4 Bosch had the foresight (course maybe it was aftesight, I'm not sure) to include tables that would allow for a boost setup up to 1.0bar of boost.
Little commerical interruption. Bar is a metric way of measuring pressure. In this case the measurement is kg/cm^2, where in the US we use PSI or lb/in^2. 1.0bar is roughly equivilent to 14.5 PSI. The stock setup for the A4 is about .5bar or about 7PSI.
By changing the boost you cause more air to flow through the engine in turn making more power. But you just can't add air. Just adding air without adding fuel it BAD! can you say M-E-L-T-D-O-W-N. So you add some fuel, now you can advance the timing to take advantage of this higher combustion and tweak power some more. This process needs to be done 100's or 1000's of times and measured with test equipment like Air fuel ratio monitors, EGT guages, fuel pressure gauges and boost pressure gauges and ultimately a Dyno to see the results. After all the above testing and verification, you can create a flash image that has new tables that represent the work of the tuner to create a power increase.
What you have for the A4 market is about 10 or so companies that are making chips (remember really flash images) that have custom tables that the processor in the ECU uses to make power and control the engine. In almost all cases these tuners have found that a .8 - 1.0bar setup will provide between 185-200HP for the A4.
As it physically relates to chips, there are at least three different ways of getting those "power tables" into the ECU; a) requires removing the "factory' chip and replacing it with a header that a chip socket fits down on. b) requires removing the "factory" chip and reprogramming it and then re-soldering it back to the board. c) no-one is using this yet, but there does exist a way to reprogram the part in place without de-soldering it, or
disassembling the ECU.
In the case of A) above you also find that these chip tuners consider their work to be their own creation and they will create a "coder" chip that allows them to "code" or scramble (it's not actually scrambled, but you get the picture) bytes in the flash part and then the "coder" chip knows how to decode the requests by the processor for instructions or table values. This "coder" chip acts as a copy protection scheme, you can read the part, but it will not look like anything valid and you can only use it with a socket with the "coder" chip installed and hence this provides copy protection. I think both Wetterauer and Garrett Lim are using this scheme. Garrett may not be yet, but I know he's going to it based upon comments I've seen on his webpage.
You will find no two "chips" behave exactly alike in your car. Each will show the individualism of it's tuner. Some may be a little better in low RPM, high Torque situations and others will favor higher RPM's.
Like I said, I'm not going to recommend. You'll have to do that research yourself or find a "chipped" A4 in your area and see what you think. Each of the chips out on the market will usually show the 185-200HP, but it might come in differnent parts of the powerband of the A4.
So, there you have it... Part 1, or was that part 2 of Chips and Salsa!
Hope this helps,
Alan
__________________________________________________ ________
Ok, let's talk about chips. Actually, more technically, let's talk about the instruction code and tables that the processor in the ECU uses to control the engine. These instructions and tables are stored in a programmable, non-volitale memory called a Flash Eprom. In the A4, Bosch uses an AMD 29f200B flash part. It's physically soldered down to the main ECU board in whats called a PSOP package. Basically a 44 pin part with little,
.050 spacing, gull wing looking pins that are soldered down.
Inside this part are both processor instructions and lookup tables for various functions. To name a few, boost, timing, fuel, RPM, idle, rev limiter, speed limiter, etc.
Ok, so that's the technical description of the parts. One other note, a flash part can be read and programmed. Obviously it can be read because the processor needs to get instuctions to execute and look at the tables as is needed. One other comment, there is RAM inside the processor or perhaps external, but either way, the little processor does just like a PC, when it's first turned on it boots (actually the lower section of the flash
part has a protected boot partition just like the boot sector on a HD), and starts running it's program which in this case controls the engine. Part of that bootup process may include downloading or loading from ROM to RAM a baseline table to be used for the various fuctions.
This table may be "tweaked" as the ECU "learns" both how you drive and the conditions the engine is running in. In NO way does the processor write this "learned" table back to the flash part. It's stored in another non-volitale RAM area and used and tweaked as needed. Usually removing the power to the ECU will clear the "learned" instructions and cause a reload of the "baseline" tables, but not under all circumstances. We won't
go there for this dicsussion.
Because a flash part can be read, a chip tuner will take an 'image' of a particular rev of code, by removing the part from the board and reading it with an eprom programmer, and modify the tables inside to produce better performance. In no cases, that I'm aware of, do they modify the instruction code in the flash, just simply the tables.
In the A4 Bosch had the foresight (course maybe it was aftesight, I'm not sure) to include tables that would allow for a boost setup up to 1.0bar of boost.
Little commerical interruption. Bar is a metric way of measuring pressure. In this case the measurement is kg/cm^2, where in the US we use PSI or lb/in^2. 1.0bar is roughly equivilent to 14.5 PSI. The stock setup for the A4 is about .5bar or about 7PSI.
By changing the boost you cause more air to flow through the engine in turn making more power. But you just can't add air. Just adding air without adding fuel it BAD! can you say M-E-L-T-D-O-W-N. So you add some fuel, now you can advance the timing to take advantage of this higher combustion and tweak power some more. This process needs to be done 100's or 1000's of times and measured with test equipment like Air fuel ratio monitors, EGT guages, fuel pressure gauges and boost pressure gauges and ultimately a Dyno to see the results. After all the above testing and verification, you can create a flash image that has new tables that represent the work of the tuner to create a power increase.
What you have for the A4 market is about 10 or so companies that are making chips (remember really flash images) that have custom tables that the processor in the ECU uses to make power and control the engine. In almost all cases these tuners have found that a .8 - 1.0bar setup will provide between 185-200HP for the A4.
As it physically relates to chips, there are at least three different ways of getting those "power tables" into the ECU; a) requires removing the "factory' chip and replacing it with a header that a chip socket fits down on. b) requires removing the "factory" chip and reprogramming it and then re-soldering it back to the board. c) no-one is using this yet, but there does exist a way to reprogram the part in place without de-soldering it, or
disassembling the ECU.
In the case of A) above you also find that these chip tuners consider their work to be their own creation and they will create a "coder" chip that allows them to "code" or scramble (it's not actually scrambled, but you get the picture) bytes in the flash part and then the "coder" chip knows how to decode the requests by the processor for instructions or table values. This "coder" chip acts as a copy protection scheme, you can read the part, but it will not look like anything valid and you can only use it with a socket with the "coder" chip installed and hence this provides copy protection. I think both Wetterauer and Garrett Lim are using this scheme. Garrett may not be yet, but I know he's going to it based upon comments I've seen on his webpage.
You will find no two "chips" behave exactly alike in your car. Each will show the individualism of it's tuner. Some may be a little better in low RPM, high Torque situations and others will favor higher RPM's.
Like I said, I'm not going to recommend. You'll have to do that research yourself or find a "chipped" A4 in your area and see what you think. Each of the chips out on the market will usually show the 185-200HP, but it might come in differnent parts of the powerband of the A4.
So, there you have it... Part 1, or was that part 2 of Chips and Salsa!
Hope this helps,
Alan
09-01-1999, 09:49 AM
#3
Guest
Posts: n/a
Re: Chipping for dummies (A Small Guide)
Turbo boost:
Stock = 0.5 Bar or 7psi
0.8 Bar = 11-12psi boost
1.0 Bar = 14-15psi boost
Stock turbo name = K03
Aftermarket larger turbo = K04
Chips usually come in two flavors:
"Spare ECU"(you swap the entire silver metal container with your stock one) and "Socketed"(your stock ECU is opened, the stock chip desoldered and a socket is installed which allows you to remove the aftermarket chip and reinsert the stock chip or send the aftermarket chip out for new coding)
Possible problems with chips:
Chip MAY or MAY NOT void warrenty depending on dealer.
Chip MAY or MAY NOT lower the life of the engine
Chip could possibly damage turbo.
Chip could cause pinging(detonation) in high heat or with poor fuel(91 octane or less)
These cars haven't been around long enough to tell how much if at all a chip effects engine life.
Advantages to chipping:
Less turbo lag
More horsepower and torque
Better acceleration
Better gas milage
Some chips can smooth out jerkiness or lag problems
YOU GO FAST!
Brand names:
TAP, APR, Garrett, Neuspeed, AMS, MTM/Hoppen, Wetterauer, Autothority and probably more that I don't know of or am forgeting.
Helpful links to learn more about turbos or these fine companies:
Don P's "Audi Zone" http://donp.tzo.com/
AWE Tuning: http://www.awe-tuning.com/
APR: http://www.goapr.com/Home/home.html
Wett: http://www.chip-tuning.com
Garrett: http://www.giacusa.com/welcome.html
TAP: http://www.tap1.com
Neuspeed/Greedspeed: http://www.greedspeed.com
Thats all I can think of off the top of my head.
I am sure there is more out there and I am sure that if you look around a4.org more you will find LOTS of info. I know I did.
Hope this helps in your quest!
-Jenner
'99.5 1.8T QMS Spoiler/Garrett 1 Bar
Stock = 0.5 Bar or 7psi
0.8 Bar = 11-12psi boost
1.0 Bar = 14-15psi boost
Stock turbo name = K03
Aftermarket larger turbo = K04
Chips usually come in two flavors:
"Spare ECU"(you swap the entire silver metal container with your stock one) and "Socketed"(your stock ECU is opened, the stock chip desoldered and a socket is installed which allows you to remove the aftermarket chip and reinsert the stock chip or send the aftermarket chip out for new coding)
Possible problems with chips:
Chip MAY or MAY NOT void warrenty depending on dealer.
Chip MAY or MAY NOT lower the life of the engine
Chip could possibly damage turbo.
Chip could cause pinging(detonation) in high heat or with poor fuel(91 octane or less)
These cars haven't been around long enough to tell how much if at all a chip effects engine life.
Advantages to chipping:
Less turbo lag
More horsepower and torque
Better acceleration
Better gas milage
Some chips can smooth out jerkiness or lag problems
YOU GO FAST!
Brand names:
TAP, APR, Garrett, Neuspeed, AMS, MTM/Hoppen, Wetterauer, Autothority and probably more that I don't know of or am forgeting.
Helpful links to learn more about turbos or these fine companies:
Don P's "Audi Zone" http://donp.tzo.com/
AWE Tuning: http://www.awe-tuning.com/
APR: http://www.goapr.com/Home/home.html
Wett: http://www.chip-tuning.com
Garrett: http://www.giacusa.com/welcome.html
TAP: http://www.tap1.com
Neuspeed/Greedspeed: http://www.greedspeed.com
Thats all I can think of off the top of my head.
I am sure there is more out there and I am sure that if you look around a4.org more you will find LOTS of info. I know I did.
Hope this helps in your quest!
-Jenner
'99.5 1.8T QMS Spoiler/Garrett 1 Bar
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