How do I mod my ECU ?!

r5b18ft · Post by **r5b18ft** » Tue Dec 16, 2008 4:14 pm

Hi guys,

I've red several posts about modding the ECU by changing or doing something to certain resistors in the ECU so you can increase the boost without having problems with the electronics.

The thing is I can't find posts that explain exactly what has to be done.. can anyone please link me to some good post or tell me exactly what to do step by step ??

Cheers,
David.

pol · Post by **pol** » Tue Dec 16, 2008 4:31 pm

I don't think it's a very popular mod on here but here is the text from the main site where someone has done this. Note, I have not tried this and cannot vouch for it and you will probably break your ECU and all that!:

The modified CEM
Let me tell you what I did to my CEM. If you open the CEM box (the one under the centreconsol) you'll find two resistors, one of them named R206 (is a double, same as R207) and the other R207. Unsolder both of them. Then solder on two cables where the R207 was and and jack them onto a potentio-meter. Then put the box back together and take the car for a ride. Start with potentiometer in the bottom, put your car in third gear, foot on the brakes and pedal to the metal (must be over 4500 rpm). Watch the pressure gauge and take note. Then turn up the potentiometre and do the same thing over and over again until you find the presure at a level you prefer, I do not recomend that you boost it up so it goes in to the red field on the original pressure gauge (~0.8 Bar), because the fuel wont be enough, it can take more, but I wont take any responsability with what you do to your cars. When youre done and satisfied with the pressure simply solder off the potentiometre and measure the resistance in the potentiometre and buy a resistance that has the corresponding value, costs almost nothing. Solder in this new resistor in your box (where the R207 was) and put it back together. Enjoy!

If you want to you can make a switch (I did so) so you can drive with the standard resistance and standard boost if you want to. I've got one stage (standard) 0.5 Bars, and switched ~+0.8Bars.

The car will respond very well in the higher revs (4500 and up). The MBC makes the car go fast at ~3000 rpms. I've combined these two mods so the car goes fast from 3000rpms and up. So far my car has managed about 1Bar with no problem, but that's just for 'special occasions'.

Warning, the original booststop at 0.9 Bars doesn't work when you've done this modification! So if you turn up your MBC the turbo will run until it blows if you don't do it with moderation and common sense...

Pics and instructions in swedish made by Peter, the 'inventor' of this :
http://www.480center.com/servlet/user?a ... cle&id=332

pol · Post by **pol** » Tue Dec 16, 2008 4:33 pm

Most people try and get their ECU's modified by another member on the forum. Search for a sticky thread in the tuning and tweaking section of the forum.

http://volvo480.dragons.org.uk/forum/vi ... hp?t=16209

pol

greasy mits · Post by **greasy mits** » Wed Dec 17, 2008 12:39 am

best way is to go megasquirt that richmod seems impossible to get