Click Here for 2003-2003.5 MazdaSpeed Protege install pics and instructions..

NOTE - These instructions are not vehicle-specific. Feel free to contact me if you have any questions regarding the installation.

Installing the MBC-

1) Locate the turbo outlet and wastegate and remove all hoses from them. You will not be needing these lines for installation, but it is recommended you keep them so you can easily go back to stock configuration at any time.

2) Use two of the included wire ties to attach boost control valve to a convenient location (Remember - you will need to access the MBC to adjust boost levels).

3) Run a 3/16" ID (inside diameter) hose from the fitting on the bottom of the boost controller to the nipple on the turbo outlet.

4) Run a second 3/16" ID (inside diameter) hose from the fitting on the side of the controller to the wastegate.

Before testing, make sure all hoses are installed and secured properly with the supplied wire ties and that the locknut on the adjusting screw is tight.

Setting boost levels - This boost controller does not come preset. You are responsible for setting it to a safe level. To adjust the controller, loosen the lock nut and turn the adjusting screw clockwise to increase boost, counter-clockwise to decrease it. This will take a little time to get right, be patient. The adjusting screw is sensitive. If you get too carried away with it, you can overboost and engine damage may occur. I don’t recommend going more than a half turn at a time, LOCKING THE LOCKNUT AFTER EACH ADJUSTMENT, until you get within a couple psi of your desired setting, then go 1/8-1/4 until you reach it.

NOTE: You want to set the max boost level with a load on the engine- third gear works well for this. Be sure to tighten the locknut whenever you adjust the boost to prevent the adjusting screw from falling out!

You should now be finished with the installation and setting up of your boost controller. If you have any questions, feel free to contact me at tech@joepmbc.com

DISCLAIMER- THE BUYER IS RESPONSIBLE FOR PROPER INSTALLATION AND ADJUSTMENT OF THE BOOST CONTROLLER VALVE. ALTERING ANY VEHICLE FROM IT’S STOCK CONFIGURATION CAN BE DANGEROUS AND/OR CAUSE FAILURE. IF YOU FEEL YOU ARE UNABLE TO SAFELY COMPLETE THIS INSTALLATION, YOU MAY WANT TO CONSIDER BRINGING THE VEHICLE TO A PROFESSIONAL OR CONTACT JOE P. FOR FURTHER ASSISTANCE. JOE P. IS NOT LIABLE FOR ANY DAMAGES OR INJURY DUE TO USING THIS MANUAL BOOST CONTROLLER.

Additional items required for installation-
* Reliable boost gauge (most stock ones are inaccurate)
* 3/16" ID (inside diameter) hose
* Wire cutters or a strong pair of scissors (to cut hose and wire ties)
* Extra wire ties (not necessary, but may prove useful)
It is also strongly recommended that you have an upgraded fuel pump along with a fresh fuel filter installed. Remember- increasing boost will increase airflow - you need to have a reliable fuel supply.