This engine is a Mazda BP-26. Internally it is completely stock. The customer has blown the engine up several times using a stock ECU with stock VAF MSD boost retard and apexi SAFC. Stock management is simply not up to the task

The owner is looking to have about 200whp.

Engine Control

The plan is to have a fully sequential wasted spark fuel management system. Wasted spark was chosen because I will be using standard GM 2 post coils and I am not planning to implement any per cylinder ignition trims. The coils were taken from a Chevy Cavalier and the mounts offer the ability to upgrade to a larger performance coil pack.

Detonation detection is a possibility as the engine came equipped with a knock sensor. While this will be wired in I'm not sure that I will be using it yet.

The car has a standard resistive TPS sensor so I will be supplying +5V to one side and GND to the other.

+5V can come directly off an onboard L7805 (EC36-pin28 HALLsupply) or after a 270 Ohm protection resistor (EC36-pin29) TPS5V output. When using the same source for different units (eg. HALL + TPS), it's a good idea to provide the weakest, smallest current-limit one to the TPS (TPS can be easily calibrated anyway).

The car is also equipped with a hall effect distributor. MembersPage/Fero has been successfully using this ford/mazda distributor with success so I will be using his scheme for the primary and trigger. I'm not too parial on using cam based triggers but the alternative isn't much better considering it's harsh environment.

CLT sensor will be using the mazda sensor. This differs from the domestic temp sensors but most imports seem to have this in common. Subaru, Honda and Mazda all use the same resistive profile.

IAT sensor is mounted after the intercooler and just before the throttle body. Due to the availibility I am using a standard honda IAT sensor. They're easily found in scrapyards and the plugs are just as common.

Boost control is accomplished via a 3 way solenoid valve. In the rest (and failure) state this valve routes boost directly to the wastegate. In the powered state it plugs the boost supply and diverts the wastegate to the atmosphere. I am using a humphres valve with integrated weatherproof connector.

The MAP sensor uses the supplied (WebShop) MPX4250AP motorola sensor. I'm not partial to having a long vacuum hose into the passenger compartment. In my experience this does not lead to a very responsive engine. I will machine a protective case for this sensor (sounds nice. more details / photos?) and mount it close to the throttle body.

I am using the factory cooling fan relay for electronic fan control. I have the option to use the factory radiator installed thermoswitch but with 1.8l 4 cylinder engines switching a fan on can sometimes cause them to stall. With electronic fan control I can cause the ECU to increase the IAC duty cycle to maintain a constant idle speed.

The econoseal plug is wired via 24" of cable to a panel mount CPC round 24 position connector. This inexpensive connector provides a clean and weatherproof hookup between the engine and the firewall. There is a separate plate that covers a stock firewall hole and it is large enough to pass all the EC connectors inside for ease of installation.

The O2 sensor wiring passes via it's own separate chassis wire and be plugged in near the front of the engine.