http://underground2l.blogspot.cz/2008/06/parts-for-cars.html (the page about visual parts is a lie, they have no effect on car's performance)

Single gold bar glitch:

1. Install stage 1 ECU
2. Go to DYNO and push down on the 1st bar in ECU
3. Install stage 2 and 3 ECU.
4. Go to DYNO and you will see a gold bar in ECU

Double gold bar glitch:

1. Build a new car
2. Equip all performance parts except for ECU.
3. Save before DYNO
4. Max Turbo bars 4-9¤ The number of bars will vary with the car chosen.
5. Run the DYNO
6. Leave DYNO and go to Performance parts 7 )Equip Stage 1 Turbo.
7. Go to DYNO, push down on the last two bars in Turbo.
8. Run the DYNO
9. Leave DYNO and go to Performance Parts
10. Equip Stage 3 Turbo 12)Go to DYNO, You will see a gold bar in the Turbo. Push it down just once. It will be in 7,8,or 9
11. Push down the 4 Bar to fill up 5-9. In order to fill up four you push down 3-0 in that order. Keep doing it until 3-0 is empty.
12. Repeat steps 7,8 then repeat steps 12,13

¤When Four gets maxed out, max out the 3 bar in the same process by pushing down 2-0

When 3 is maxed out or at least 3/4 of the way there. Stop and move to ECU glitch.

ECU Glitch<<>>>

1. Go to Performance Parts and go to ECU.
2. Manually install the first 4 parts-Dont buy the stages
3. Then skip performance chip, install the next one
4. Skip engine management, then install last one
5. Go to DYNO
6. In ECU, put first two bars all the way down. If they dont then you did not do the first part long enough.
7. Run DYNO
8. Leave DYNO and go to Performance parts
9. Install Perf. Chip then Engine Management<<must be in this order.
10. Go to DYNO-should be two gold bars on the first 2 bars.

Triple gold bar glitch:

¤NOTE¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤ You need to do double gold bar again. There will be asteriks where i made changes in steps.

1. Build a new car
2. Equip all performance parts except for ECU.
3. Save before DYNO
4. Max Turbo bars 4-9¤ The number of bars will vary with the car chosen.
5. Run the DYNO
6. Leave DYNO and go to Performance parts
7. Equip Stage 1 Turbo.
8. Go to DYNO, push down on the last two bars in Turbo.
9. Run the DYNO
10. Leave DYNO and go to Performance Parts
11. Equip Stage 3 Turbo
12. Go to DYNO, You will see a gold bar in the Turbo. Push it down just once. It will be in 7,8,or 9
13. Push down the 4 Bar to fill up 5-9. In order to fill up four you push down 3-0 in that order. Keep doing it until 3-0 is empty.
14. Repeat steps 7,8 then repeat steps 12,13

¤When Four gets maxed out, max out the 3 bar in the same process by pushing down 2-0

When 3 is maxed out or at least 3/4 of the way there. Stop and move to ECU glitch.

ECU Glitch<<>>>

1. Go to Performance Parts and go to ECU.
2. Manually install the first 4 parts-Dont buy the stages
3. Then skip performance chip, install the next one
4. Skip engine management, then install last one
5. Go to DYNO
6. In ECU, put first two bars all the way down. If they dont then you did not do the first part long enough.
7. Run DYNO
8. ¤¤Now DO NOT install Perf chip or Engine Mananagement yet.
9. Go to Turbo and push the last bar all the way down. Then run it on DYNO¤NOTE¤ Triple only works for the Corolla¤¤¤
10. There will be a tiny ass amount of blue on the last bar. Push it down once then dyno it. Then go back to the last bar and push it down once again. Then DYNO it. Keep doing this pattern until all the bars are maxed except the last bar.
11. Now push down the 3rd bar in ECU. ¤NOTE¤ if 1 and 2 raise keep pushing down all 3 until the blue disappears.
12. Install Performance chip and Engine management.
13. In ECU you will see 2 gold bars there isnt actually a 3rd gold bar but it will be all the way down.
14. Now do normal Turbo Glitch 6-0

Unverified:

First you install lvl 1 turbo and ECU then you go to the dyno once you there you go to the turbo and put the 6 bar all the way down and the 8 bar half way... then you go install lvl 3 turbo and go back to the dyno once you there you go to the turbo and you will see a gold bar , you go to that bar and click it down one time... then you go install lvl 1 turbo again and go to the dyno put the 6 bar in the turbo all the way down and the 8 bar half way and then go install lvl 3 turbo you go back to dyno and click one time doen on the gold bar.... you just keep doin this until all you bars all full exept for your 6 and your 8...your 8 should be just a litle bit empty like one click before it fills up once this happens you install lvl 2 turbo and do the same thing u did with lvl 1... u put the 6 bar all the way down and the 8 half way...u just keep doin that till allur bars are full exept ur 6....once u done u go install lvl 3 turbo if u dont have it installed already u go to the dyno and go to the ecu and on the first bar u cilck one time down... u will see all ur bars drop ...then u will put the first 3 bars all the way down and the u click the 4 bar one time down...after that ur first 3 bars will go up just a litle bit ..but dont touch them go dyno ur car and then go install lvl 2 adn 3 ecu..then go back to the dyno and reset ur turbo ...and u will have from 495-500 hp in ur car if u did it correctly.... then just do the normal turbo glitch

Turbo glitch #1:

Install Lvl's 1,2,3 then go to the dyno then go to the turbo then put bars 1,2, & 3 down then dyno your car then go back to the turbo and put 4 down once then 3 down once then 2 down once then 1 down once keep doing this till 1,2,3,4 are completely gone then just do the same thing you just did till the 5 and 6th bars are gone dont try to do MORE THEN ONE BAR AT A TIME THIS WILL MESS THE GLITCH UP AND IT WILL TAKE YOU FOREVER TO GET IT DONE IF IT DOSE WORK DO ONE BAR AT A TIME

Turbo glitch #2:

Install level three turbo on your car. Go to the dyno and tune settings. Go to the turbo and put the last three bars on the right all up. Set all the other bars down one starting from the left going to the right. Dyno your car and your horsepower should increase as well as your 0-60

NOS glitch #1:

First install lvl 1 NOS go to dyno in the NOS put the the NOS all the way to the right... then go and INSTALL lvl 2 NOS go bak to dyno and put the nos all the way to the LEFT... then go back and install lvl 3 NOS go back to dyno and setup the NOS at 6!!

NOS glitch #2:

Start with stock nitrous. Then install level one nitrous and got to dyno and tune settings. Go to nitrous and put it all the way to the left. Dyno your car and then leave the dyno. Install level two nitrous and go to dyno and tune settings. Go to the nitrous and put it all the way to the right. Dyno your car then leave the dyno. Install level three nitrous and go to dyno and tune settings. Go to nitrous and set it to six. Dyno your car and leave. Now when you spray your nos you will have better power and duration than before

Steroid #1 (TURBO)

Install all three levels of performance upgrades, then go to the dyno. Go to turbo under tune settings and put 7-9 all the way up. Then put 6,5,4,3 down one click. Leave the turbo and go to the ECU. Put 9-6 all up and 5,4,3 down

Steroid #2 (TURBO)

Install level three performance on your turbo. Go to the dyno. Enter tune settings and go to turbo. Put 1-4 all the way up. Leave the dyno. Install level one performance on your turbo. Go back to the dyno and tune settings. Put 5-9 all the way up and leave the dyno. Re-install level 3. NOTE: Every time you do this, it will give you about five horsepower. If you do this for a while it should give you a ton more horses for your car

Steroid #3 (ECU)&(TURBO)

Put level three turbo and ecu on your car and go to dyno. Go to tune settings and then turbo. Put 7-9 all up and 6-3 down once. Go to the ECU and put 9-6 all up and 5-3 down once.

ECU glitch:

Install level three ECU and go to dyno and tune settings. Go to ECU and put bars 7-9 all up. Put bars 5-3 down once and repeat that until bars 1,2,6,7,8,9 are all up.

Non career rubberband glitch: Install level one ECU. Go to the dyno and tune settings. Go to the ECU and put the cursor on the last bar. Put a rubberband around the right analog stick on the controller so it is only pushing up the ninth bar continuously. Leave the game on with the rubberband for a long time and your horsepower should increase as time moves on. When you have let it sit for as long as you want, remove the rubberband, dyno your car and install level 2 and 3 ECU upgrades.

Career rubberband glitch:

You need a unique ECU/Turbo "Turbo Is Best" for this glitch to work. Go to dyno and tune settings. Go to the ECU and go to the last bar. Put a rubberband around the ninth bar so it is pushing that one up only. Leave it there and horsepower will increase with time. Remove the rubberband when you want to and your horsepower will drastically increase.