Ideal Spark Plugs for 4.0 ?
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From: AnkaraTurkey
Year: 1997
Model: Grand Cherokee
Engine: 4.0
I am using stock plugs which are stated on users manual but problem is, i am using LPG instead of Gasoline and this requires the tighter gap at tip. Any information? LPG has higher octane rating when compared to gasoline(actually it is not called octane for LPG but it is not important)
What is stock gap for gasoline? Which alternative brands can be used with 4.0 engine? it is 97 ZJ 4.0.
What is stock gap for gasoline? Which alternative brands can be used with 4.0 engine? it is 97 ZJ 4.0.
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From: Aberdeen, MD
Year: 1995
Model: Cherokee
Engine: 4.0L HO I-6, 703 Injectors, Brown Dog Super Engine Mounts
stock gap is .035.
There are special plugs you can buy for the petrol/LPG combination - do a search online, pretty sure they are manufacturer specific (non-standard)
There are special plugs you can buy for the petrol/LPG combination - do a search online, pretty sure they are manufacturer specific (non-standard)
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Joined: Oct 2010
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From: AnkaraTurkey
Year: 1997
Model: Grand Cherokee
Engine: 4.0
LPG is liquid petrolium gas(actually liquid propane gas). my 4.0 operates on LPG. it is cheaper than gasoline.
if it is 0.035 which makes almost 0.9 mm, i need to find different spark plugs.
another question, do 4.0 have knock sensors for each cylinders?
if it is 0.035 which makes almost 0.9 mm, i need to find different spark plugs.
another question, do 4.0 have knock sensors for each cylinders?
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Joined: Sep 2009
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From: Everett, WA
Year: 1990
Model: Cherokee
Engine: 4.0l
Your running LP!? could you take a look at my thread and maybe give your 2 cents? I'm looking at doing a petrol/LP setup and could use some input..
https://www.cherokeeforum.com/f2/run...00-carb-64773/
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Joined: Feb 2010
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From: gloucester va
Year: 1990
Model: Cherokee
Engine: 4.0
i want to know the lpg conversion more like how you did it and how expensive was it i have a "90 renix motor and was tossing the idea of lpg around but dont know anything about it
I too need more info. I have always wanted to run LP. More power less cost less moving parts and can be used at more extream angles. Haven't looked into it yet but now you make me want to. I have 2, 4.0 H.O.s a 95 and 99 please do a write up and give me a link. I'm tearing down the 95 soon and would love to add this to the list of mods.
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From: The Republic of TEXAS
Year: 1998
Model: Cherokee
Engine: 4.0L HO
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Joined: Oct 2010
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From: AnkaraTurkey
Year: 1997
Model: Grand Cherokee
Engine: 4.0
dear friends, i will take photos and try to introduce you a LPG system.
It is better to open a new topic for that.
thanks for answer. i will check your thread.
It is better to open a new topic for that.
I think only the Renix 4.0's have knock sensors and theres only one under the intake/ exhaust manifolds on the drivers side. It uses a pezo crystal to create a pulse when detonation occurs.
Your running LP!? could you take a look at my thread and maybe give your 2 cents? I'm looking at doing a petrol/LP setup and could use some input..
https://www.cherokeeforum.com/f2/run...00-carb-64773/
Your running LP!? could you take a look at my thread and maybe give your 2 cents? I'm looking at doing a petrol/LP setup and could use some input..
https://www.cherokeeforum.com/f2/run...00-carb-64773/


