[Wolfman01]

1997 4.0L HO engine vs. 1998 4.0 engine.

Back when I bought my 98 Cherokee, I had also purchased a 1997 Cherokee with the 4.0 "high output" engine. While I don't have the '97 anymore, what is the difference, if any between the two, and what are the HP/torque specs? TIA.

[Chris_Walker]

It pretty much is the same HP and Torque, except that Chrysler made the exhaust ports on 98+ 4.0's itty bitty so it would be more environmentally friendly.

[dyna]

4.0L I6
Bore x Stroke 3.88" x 3.41"
Displacement 242 (4.0L)
Compression Ratio 8.8:1
Horsepower (net) 180@4750
Torque (net) 220@4000
Main Bearings 7
Valve Configuration OHV
Fuel MPI


The 4.0L I6 that is used in the XJ and ZJ is rated slightly higher than the YJ and TJ 4.0L engine probably due to a different exhaust system.

4.0L I6
Bore x Stroke 3.88" x 3.41"
Displacement 242 (4.0L)
Compression Ratio 8.8:1
Horsepower (net) 185@4750
Torque (net) 220@4000
Main Bearings 7
Valve Configuration OHV
Fuel MPI
The Jeep 4.0 litre I6 engine is a pushrod overhead valve design with 2-valves/cylinder. The factory power ratings are as follows:

'87...... XJ: 173hp at 4500rpm, 220lbft @ 2500rpm, redline 5000rpm
'88-'90 XJ: 177hp at 4500rpm, 224lbft at 2400rpm, redline 5000rpm
'91-'95 XJ: 190hp at 4750rpm, 225lbft at 3950rpm, redline 5250rpm
'96-'99 XJ: 190hp at 4600rpm, 225lbft at 3000rpm, redline 5300rpm
'00-'01 XJ: 193hp at 4600rpm, 231lbft at 3000rpm, redline 5300rpm

'91-'95 YJ: 180hp @ 4750rpm, 220lbft @ 3950rpm, redline 5250rpm
'96-'99 TJ: 181hp @ 4600rpm, 222lbft @ 2800rpm, redline 5300rpm
'00-'06 TJ: 190hp @ 4600rpm, 235lbft @ 3200rpm, redline 5300rpm

'93-'95 ZJ: 190hp @ 4750rpm, 225lbft @ 3950rpm, redline 5250rpm
'96-'98 ZJ: 185hp @ 4600rpm, 220lbft @ 2400rpm, redline 5300rpm
'99-'05WJ:195hp @ 4600rpm, 230lbft @ 3000rpm, redline 5300rpm


This is a bit from "jeeptech" pages. Yes the HO made more ponies

[Wolfman01]

Originally Posted by dyna

4.0L I6
Bore x Stroke 3.88" x 3.41"
Displacement 242 (4.0L)
Compression Ratio 8.8:1
Horsepower (net) 180@4750
Torque (net) 220@4000
Main Bearings 7
Valve Configuration OHV
Fuel MPI


The 4.0L I6 that is used in the XJ and ZJ is rated slightly higher than the YJ and TJ 4.0L engine probably due to a different exhaust system.

4.0L I6
Bore x Stroke 3.88" x 3.41"
Displacement 242 (4.0L)
Compression Ratio 8.8:1
Horsepower (net) 185@4750
Torque (net) 220@4000
Main Bearings 7
Valve Configuration OHV
Fuel MPI
The Jeep 4.0 litre I6 engine is a pushrod overhead valve design with 2-valves/cylinder. The factory power ratings are as follows:

'87...... XJ: 173hp at 4500rpm, 220lbft @ 2500rpm, redline 5000rpm
'88-'90 XJ: 177hp at 4500rpm, 224lbft at 2400rpm, redline 5000rpm
'91-'95 XJ: 190hp at 4750rpm, 225lbft at 3950rpm, redline 5250rpm
'96-'99 XJ: 190hp at 4600rpm, 225lbft at 3000rpm, redline 5300rpm
'00-'01 XJ: 193hp at 4600rpm, 231lbft at 3000rpm, redline 5300rpm

'91-'95 YJ: 180hp @ 4750rpm, 220lbft @ 3950rpm, redline 5250rpm
'96-'99 TJ: 181hp @ 4600rpm, 222lbft @ 2800rpm, redline 5300rpm
'00-'06 TJ: 190hp @ 4600rpm, 235lbft @ 3200rpm, redline 5300rpm

'93-'95 ZJ: 190hp @ 4750rpm, 225lbft @ 3950rpm, redline 5250rpm
'96-'98 ZJ: 185hp @ 4600rpm, 220lbft @ 2400rpm, redline 5300rpm
'99-'05WJ:195hp @ 4600rpm, 230lbft @ 3000rpm, redline 5300rpm


This is a bit from "jeeptech" pages. Yes the HO made more ponies

Thanx. This is exactly what I was looking for.

[BassPlayer]

Originally Posted by Wolfman01

Thanx. This is exactly what I was looking for.

This was exactly what I was wondering, I own a 1997 Jeep Cherokee 4.0 Litre "High Output" model myself, and am wondering how much horsepower I should be getting, 180 or 185? Or more?

[curtjames37]

Originally Posted by BassPlayer

This was exactly what I was wondering, I own a 1997 Jeep Cherokee 4.0 Litre "High Output" model myself, and am wondering how much horsepower I should be getting, 180 or 185? Or more?

Should be making 190 according to stock specs.

[alexrule123]

Originally Posted by C.Walker

It pretty much is the same HP and Torque, except that Chrysler made the exhaust ports on 98+ 4.0's itty bitty so it would be more environmentally friendly.

actually i believe it was from 99+. since in 99 they came out with the new intake manifold