The 2.5L inline 4 (I4) engine used in Jeeps today was first introduced
in '84 when Jeep was owned by AMC. Originally, the engine used a
carburetor, later versions used throttle body fuel injection, and
the current version uses multi-port fuel injection. The fuel
induction has been the major change with this engine over the
years. The 2.5L uses over head valves with hydraulic lifters and
a cast iron block and cylinder head.
The current version of the 2.5L I4 engine uses multi-port fuel
injection. This engine is the standard engine used in the Wrangler
(TJ) and Cherokee (XJ). It was the standard engine in the Wrangler
(YJ) since 1991. The XJ version of the 2.5L has a slightly higher
output.
| AMC 150 I4 |
|---|
| Bore x Stroke | 3.88" x 3.19" |
| Displacement | 150ci (2.5L) |
| Compression Ratio | 9.1:1 |
| Horsepower (net) | 123@5250 |
| Torque (net) | 139@3250 |
| Main Bearings | 5 |
| Valve Configuration | OHV |
| Fuel | MPI |
The TBI version of the 2.5L was used in '87-'90 Wrangler YJs.
| AMC 150 I4 |
|---|
| Bore x Stroke | 3.88" x 3.19" |
| Displacement | 150ci (2.5L) |
| Compression Ratio | 9.2:1 |
| Horsepower (net) | 117@5000 |
| Torque (net) | 135@3500 |
| Main Bearings | 5 |
| Valve Configuration | OHV |
| Fuel | TBI |
This carbed version of the AMC 150 I4 was introduced as the
standard engine in '84-'86 CJ-7s.
| AMC 150 I4 |
|---|
| Bore x Stroke | 3.88" x 3.19" |
| Displacement | 150ci (2.5L) |
| Compression Ratio | 9.2:1 |
| Horsepower (net) | 105@5000 |
| Torque (net) | 132@2800 |
| Main Bearings | 5 |
| Valve Configuration | OHV |
| Fuel | 1bbl |