4.2 vs 4.0
#2
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
They went from 4.2 to 4.0.
#3
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Year: 1996
Model: Cherokee
Engine: 4.0L
The AMC 4.2 was never available in the XJ.
The 4.2 was in the YJ until 1990, and was available in the full size cherokee, CJ, j10 and j20 pickups and some others.
The 4.2 was in the YJ until 1990, and was available in the full size cherokee, CJ, j10 and j20 pickups and some others.
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Year: 97
Model: Cherokee
Engine: 4.0L
Huge difference, 4.2 is carbed. XJs never had a 4.2 but YJs did, my 87 has it. The 4L makes more HP, torque and has fuel injection. I can hop in my XJ and go, my YJ has to warm up a bit. The 4.2 was used for a long time and the 4L was it's replacement.
#5
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Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
4.2L makes a lot more torque on the low end, the stroke is longer. 4.0L is way more fuel efficient and has better top end. Plus MPFI is vastly superior to any carb setup in an offroader, if not any vehicle.
Put 4.2L crank and rod into a 4.0L and make a monster engine. Best of both worlds.
Read here: http://en.wikipedia.org/wiki/AMC_straight-6_engine
Put 4.2L crank and rod into a 4.0L and make a monster engine. Best of both worlds.
Read here: http://en.wikipedia.org/wiki/AMC_straight-6_engine
#6
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Year: 1993
Model: Cherokee
Engine: 4.0 Litre
Doesn't the 4.2 make its peak torque at 1200 rpm? I haven't looked at the specs recently but I thought it was 1200 for the 4.2 and 1800 for the 4.0.
While the 4.0 makes more torque on paper the super low rpm power if the 4.2 has it's advantages in the real world.
I know there I an actual stroker kit for the 4.0. I'm assuming the hybrid 4.2/4.0 salad speaks of is essentially a stroked 4.0.
While the 4.0 makes more torque on paper the super low rpm power if the 4.2 has it's advantages in the real world.
I know there I an actual stroker kit for the 4.0. I'm assuming the hybrid 4.2/4.0 salad speaks of is essentially a stroked 4.0.
#7
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Edit: And 4.0 rods.
Last edited by Hayden98XJ; 01-06-2014 at 06:08 PM.
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#9
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Year: 1990
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