Mazda 323 with a KL-ZE V6

The fifth generation Mazda 323 could only be purchased with an inline-four. The owner of this 1988 323 sedan wanted a few more cylinders so he swapped to a 2.5 L KL-DE V6 from a 1994 Probe GT. He also installed a Mazda 626 engine harness, MAF, and ECU. To keep up with the extra power a five-speed manual transmission from a Mazda MX-3 was installed along with MX-3 V6 axles.

Eventually the 164 hp (122 kW) and 156 lb-ft (212 Nm) produced by the KL-DE wasn’t enough so the owner went with a more powerful 2.5 L KL-ZE V6 only found in Japan. This motor was capable of producing 199 hp (149 kW) and 165 lb-ft (224 Nm) from the factory.

The engine was upgraded with K1 H-beam rods, Wiseco 11.5:1 pistons, ported and polished KL-01 heads, KL-31 intake, Interprep valve springs, and Interprep 280/9.4 (.370 lift) cams. All this was topped off with Bosch 250 cc injectors and Hayabusa individual throttle bodies. Before the ITBs the engine made 218 horsepower and 173 lb-ft of torque to the rear wheels (dyno video below). The drivetrain was improved with an ACT 6-puck unsprung clutch and Fidanza 9 lb flywheel. The combo was good enough to send the little sedan down the quarter-mile in 12.82 sec at 106 mph.

Source: Club Protege (long detailed build thread) and ProbeTalk (condensed build thread)