3) Nissan KA24E

What Goes Wrong When Marketing Makes Engineering Decisions

In 1989, Nissan released the 240SX in the USA. The Japanese counterparts, the 180SX and Silvia S13 were equipped with the new 187 bhp, turbocharged, dual overhead camshaft CA18DET. Unfortunately, Nissan decided to market the sport compact coupe and hatchback (for 1989 and 1990) in the USA with the 140 horsepower, single cam, 12-valve KA24E. This engine was shared with the Nissan Hardbody and Frontier truck platforms. Even with a higher compression ratio (9.1:1 versus 8.6:1), girdled main caps and piston oil squirters, the KA24E had decent torque but mediocre horsepower. The 12-valve cylinder head relied on a rocker arm valvetrain (which was upgraded to a direct actuation, shim over bucket system in the dual-cam KA24DE from 1991-1998) and a single camshaft for valvetrain actuation. The good news is that the iron block is durable and tough. The bad news includes the limited flow characteristics of the 12-valve cylinder head, the single camshaft and the long piston stroke (96mm) which inhibits the extraction of significant horsepower. The aftermarket wasn’t terribly thrilled either, which left KA24E enthusiasts with few aftermarket options to choose from. With few benefits and plenty of drawbacks, the KA24E earned itself the number three spot on the list.

OPINION
WHAT’S HOT:

• Iron Block

• Durable and tough

• Free or very affordable engine to acquire

• Not half bad when properly turbocharged

WHAT’S NOT:

• Three valve head (12V)

• Single cam

• Rocker arms

• Low output

• Limited peak engine speed due to long stroke

• Limited aftermarket support

• The fact that it should have been a CA18DET or SR20DET

SPEC SHEET