KA24DE: Engine Basics and Specs
The KA24DE is a 2.4L inline four-cylinder engine that uses an iron cylinder block with an aluminum cylinder head. Part of the reason Nissan used an iron cylinder block was to save money. The engine was intended for use in light trucks and SUVs, so weight saving wasn’t a significant concern. Early versions of this engine used a SOHC design with three valves per cylinder. Even with its relatively large displacement, the KA24 did not implement balance shafts.

Later versions of this engine used a DOHC design with four valves per cylinder which increased power and efficiency. Oddly enough, Nissan decided to use a shim-over-bucket configuration for the valve train instead of rocker arms. The KA24 uses a Hitachi sequential electronic fuel injection system. Nissan configured some KA24 engines for front wheel drive vehicles.

Production Run: 1988 – 2004
Displacement: 2389cc
Cylinder Block Material: Cast Iron
Cylinder Head Material: Cast Aluminum
Valvetrain: SOHC | Three Valves per Cylinder (1988 – 1997) – DOHC | Four Valves per Cylinder (1991 – 2004)
Stroke: 96mm
Bore: 89mm
Compression Ratio: 8.6:1 to 9.5:1
Horsepower: 134hp to 155hp
Torque: 152 lb-ft to 160 lb-ft
Deck: Open Deck
Configuration: Inline Four Cylinder
Cars That Came With the KA24DE
Nissan put the KA24E and KA24DE in a variety of different products through their life cycles. Some engines were destined for light duty pickup trucks and SUVs such as the Nissan Hardbody or Nissan Xterra, but the KA24 is best known for its appearance in the 240SX. It makes sense just to adapt the engine for multiple platforms rather than creating an all-new engine.

1989 – 1990: Nissan 240 (KA24E)
1990 – 1997: Nissan Hardbody (KA24E)
1990 – 1995: Nissan Pathfinder (KA24E)
1989 – 1995: Nissan Access / Nissan Prairie (KA24E)
1990 – 1992: Nissan Stanza (KA24E)
1989 – 1992: Nissan Pintara / Ford Corsair (KA24E)
1993 – 1996: Nissan Terrano II (KA24E)
2000 – 2004: Nissan Xterra (KA24DE)
1998 – 2008: Nissan Frontier (KA24DE)
1991 – 1998: Nissan 240SX (KA24DE)
1997 – 2000: Nissan R’nessa (KA24DE)
1998 – 2001: Nissan Presage (KA24DE)
1999 – 2001: Nissan Bassara (KA24DE)
1993 – 1997: Nissan Bluebird (KA24DE)
1993 – 2001: Nissan Altima (KA24DE-a)
KA24DE: Known Problems
Just like any other engine, the KA24DE has a couple of known issues that are common. The distributor is known for failing on earlier versions of the KA24. Another prevalent issue is a rattling timing chain, which occurs when the timing chain gets loose from age and begins to rub against the timing chain cover.

Supposedly the alternator fails more than many other vehicles, but we are not able to verify this problem. The last issue is the valve cover gasket which is known for leaking, which is mostly due to the bolt pattern and design of the valve cover. It’s a pretty quick and easy fix, but it is a common occurrence.

KA24DE: Tuning Potential
Thanks to the massive explosion of drifting, the 240SX has become the most popular tuner car in the world. Although many people upgrade to the SR20DET engine, many stay with the KA24DE because of its larger displacement. A naturally aspirated built can reach up to 200whp (230bhp), but it isn’t cheap. This kind of build requires full bolt-on, ported and polished head, bigger cams, and possibly a higher compression ratio.

Many people prefer the turbocharged route as it’s relatively cheap and makes pretty decent amounts of power. Although many people use an eBay turbocharger or the SR20 turbo, the better option is to use a quality turbo. Something like a Garrett GTX2867R would easily make 400whp or more. If you want excellent throttle response and lot’s of low-end torque, a Borg Warner EFR turbo would be a great solution. Unfortunately, the stock bottom-end isn’t strong and can only hold up to about 350whp. If you’re looking to go for big power, you’ll need a forged rotating assembly. If you end up dumping that much money into a KA24, you might as well swap in a 1JZ/2JZ or RB engine which will make way more power while also being more reliable.

Ka24E vs KA24DE
There seems to be quite a lot of confusion about the differences between the KA24E and the KA24DE. As you may expect, these engines are very similar, but there are a few fundamental differences that separate these engines. The most significant difference is the cylinder head.

The Ka24E was a single overhead cam engine with just three valves per cylinder, and the KA24DE was a dual overhead cam engine with four valves per cylinder. If you didn’t already know, the biggest power gains of any engine are found in the cylinder head. It was mostly the trucks that use the KA24E, but the 89-90 240SX also used it. Luckily, the 1991 – 1998 240SX used the KA24DE.

Design improvements of the dual cam engine include the use of a knock sensor, larger diameter girdled main bearings in the Japanese block, different oil pan, different oil pickup, dipstick location, and piston oil squirters.