Hello guys,
I'm going alone into a big diagnose of my engine and I gess some of you can give any advice or ideas on the point.
I ported the head of my XJ 4.0L 91's while I was repairing the engine, as I bought the Jeep in a really bad shape. I followed the directions on the Dino's excellent page and changed bearings, rings and water pump. The new head (0331) was ported and milled 0.254mm (0.010") to increase compression in a attempt to contain the gas mileage and making a more efficient powerplant. The throttle body was also bored and I replaced the bad TPS with a spare one from my 2.5L YJ.
Spark plugs where also replaced with a used good ones, as the olds where all wrecked.
The result wasn't expected by me. It has a very stable iddle.
The smoke on tail pipe is clear an no smelling (perhaps a little burnt firecracker smell)
The power is biiiig and comes from the very bottom as it revs 'til 5500
But it has a very poor mileage of 20L/100Km (11,8 mpg) that worries me more than a lack of power.
It also overheats the exhaust pipe a nice bit. Figure, that in the last trail I wasn't able to see through the white smoke column that was coming from the eng compartment after I ran out of a little water splash.
The cat converter also heats very well so it smokes from its case only by cruising on the road.
I was starting to buy all new sensors around, but before wanna know what you guys think about.
Gettings,
Sergio Rius Rodriguez
http://saposysalamandras.dyndns.org
I'm going alone into a big diagnose of my engine and I gess some of you can give any advice or ideas on the point.
I ported the head of my XJ 4.0L 91's while I was repairing the engine, as I bought the Jeep in a really bad shape. I followed the directions on the Dino's excellent page and changed bearings, rings and water pump. The new head (0331) was ported and milled 0.254mm (0.010") to increase compression in a attempt to contain the gas mileage and making a more efficient powerplant. The throttle body was also bored and I replaced the bad TPS with a spare one from my 2.5L YJ.
Spark plugs where also replaced with a used good ones, as the olds where all wrecked.
The result wasn't expected by me. It has a very stable iddle.
The smoke on tail pipe is clear an no smelling (perhaps a little burnt firecracker smell)
The power is biiiig and comes from the very bottom as it revs 'til 5500
But it has a very poor mileage of 20L/100Km (11,8 mpg) that worries me more than a lack of power.
It also overheats the exhaust pipe a nice bit. Figure, that in the last trail I wasn't able to see through the white smoke column that was coming from the eng compartment after I ran out of a little water splash.
The cat converter also heats very well so it smokes from its case only by cruising on the road.
I was starting to buy all new sensors around, but before wanna know what you guys think about.
Gettings,
Sergio Rius Rodriguez
http://saposysalamandras.dyndns.org