When tuning the 4EFTE people often discuss the Plug and Play ECUs. These are essentially standard ECUs with an additionaly daughterboard on the circuits to alter the map. They are available from many different JDM manufacturers, in this I will run through them and their availability. Whilst talking about Plug & Play ECUs there are some key points that are worth noting. Features Generally they provide 4 features: Remove Fuel Cut, these remove the standard boost restriction, and allow you to boost to whatver your turbo will boost you too. However remeber your standard map sensor cant see over 1.2bar(??????? is this right) Remove Speed Cut, these remove the 180kmph/112mph restriction Increased Rev Limit, Generally 8000RPM. Richer map, which is generally safer for more set ups. Self Learning Unfortunately, this is a blatent lie. The way these ECUs affix their fueling for different maps is using something known as Fuzzy Logic. Wikipedia has the following to say about Fuzzy Logic So lets take a moment to think about this. This means that rather than having a on or off switch on variables, the ECU can now read 'inbetween values'. This means the car can now be more precise in what it does, to a certain degree. This allows the ECU to fuel more generally, for more setups. This is in no way guarenteed. So you should really get a dyno to confirm AFR readings to check your fueling is suitable. The ECUs Name: I.MEC Hyper Computer Hyper Revs Image: Availability: EP91, EP82 Rarity: 5/5 Name: SARD Analyse Hyper Revs Image: Availability: EP91, EP82 Rarity: 3/5 Name: SARD Analyse Hyper Revs Image: Availability: EP91, EP82 Rarity: 3/5 Name: TOM's T.E.C.S Hyper Revs Image: Availability: EP82 Rarity: 4/5 Name: KS-ROM Hyper Revs Image: Availability: EP91, EP82 Rarity: 5/5 Name: JUN Hyper Revs Image: Availability: EP91, EP82 Rarity: 5/5 Name: JAM ECU Hyper Revs Image: Availability:EP91, EP82 Rarity: 2/5 Name: Blitz Access Hyper Revs Image: Availability:EP91, EP82 Rarity: 3/5 There are also others available, however these are the ones covered in Hyper Revs. There are also ECUs by MINEs, PAL Sports, Farina Racers, Buddy Club and others. Inside the ECU As covered briefly before, inside the ECU is a standard ECU with an additional board, called a daughter board. Normally there are two additional chips inside the ECU. One contains the changed map, but it is encrypted. This was to stop other manufacturers from being able to copy each other. The second chip is a chip that contains the decoding software, this allows the modified map to be decoded on the fly, and applied to the ECU as you drive. Generally, all the chips inside are well Epoxied in to the board. This is by design, so that if you tried to remove them, or read the serial numbers on them you would damage the chip. Buying Tips When buying a plug and play ECU the best you can do is check that the seals on the sides of the unit are intact. This proves the ECU has not been opened or tampered with, If possible fit the ecu with the seller, and then check for lack of boost cut, or increased rev limit. Finally if possible, ask the seller for a list of their modifications and a fueling print out. This could help reassure you that the ECU is suitable for your set up. Although always be sure to get the fueling checked by a reputable tuner. Choosing an ECU Choosing an ECU brand is all to do with loyalty and which you would prefer, so make the choice for the one you like, or one that has worked with a similar set up to yours and stick with it.