grinding down distributor to adjust timing???
11-24-2010, 09:47 PM
#17
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Model: Cherokee
Engine: 4.0
I just want my 4.0 to perform as best as it can right now.
Its stock right now but im going to uprage to tje newer style intake mani. And i have 703's injectors on it right now. What junkyard parts will help me for this??? Im 16 so i dont have alot of mony.
Its stock right now but im going to uprage to tje newer style intake mani. And i have 703's injectors on it right now. What junkyard parts will help me for this??? Im 16 so i dont have alot of mony.
11-24-2010, 09:49 PM
#18
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I didn't mean to start a 
, I was just trying to help a guy out, its a valid question that I asked a while back. I agree though, some people still think you can just crank the dizzy around to adjust timing. It took me about two nights of searching and reading to put all the pieces together on how the cam postion sensor, CPS, ECU, knock sensor and dizzy affect timing.
That will adjust the timing for maybe a few seconds, but once the ECU processes that the timing isn't where IT wants it to be, it will either retard or advance it to stock settings. Its not a normal dizzy, I had to put aside everything I knew about timing when learning how this system works.
, I was just trying to help a guy out, its a valid question that I asked a while back. I agree though, some people still think you can just crank the dizzy around to adjust timing. It took me about two nights of searching and reading to put all the pieces together on how the cam postion sensor, CPS, ECU, knock sensor and dizzy affect timing.That will adjust the timing for maybe a few seconds, but once the ECU processes that the timing isn't where IT wants it to be, it will either retard or advance it to stock settings. Its not a normal dizzy, I had to put aside everything I knew about timing when learning how this system works.
11-24-2010, 09:57 PM
#19
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You can not advance or retard the timeing on a 4.0 by moveing the dizzy,its all computer controled,in short the timeing is fixed.
11-24-2010, 09:57 PM
#20
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Year: 1998
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I didn't mean to start a , I was just trying to help a guy out, its a valid question that I asked a while back. I agree though, some people still think you can just crank the dizzy around to adjust timing. It took me about two nights of searching and reading to put all the pieces together on how the cam postion sensor, CPS, ECU, knock sensor and dizzy affect timing.
That will adjust the timing for maybe a few seconds, but once the ECU processes that the timing isn't where IT wants it to be, it will either retard or advance it to stock settings. Its not a normal dizzy, I had to put aside everything I knew about timing when learning how this system works.
, I was just trying to help a guy out, its a valid question that I asked a while back. I agree though, some people still think you can just crank the dizzy around to adjust timing. It took me about two nights of searching and reading to put all the pieces together on how the cam postion sensor, CPS, ECU, knock sensor and dizzy affect timing.That will adjust the timing for maybe a few seconds, but once the ECU processes that the timing isn't where IT wants it to be, it will either retard or advance it to stock settings. Its not a normal dizzy, I had to put aside everything I knew about timing when learning how this system works.
11-24-2010, 10:03 PM
#21
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Perhaps I'm failing to think outside of the box, but, would'nt manipulating the distributor cap not just be a means of bypassing a problem rather than actually fixing the underlying problem? It's my understanding that timing is controlled by the ecu. By modifying the cap you would be doing nothing more than masking the real problem would'nt you?
11-24-2010, 10:06 PM
#22
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If you want better performance and your on a budget, do a search for "budget XJ upgrades" Theres a ton out there. Also theres tons of JY mods you can do too. Everything from suspension lifts, to cooling and electric fan upgrades, to injector upgrades to name a few. googles your friend. We're more than willing to help you out, just look for the answers first.
11-24-2010, 10:13 PM
#25
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Perhaps I'm failing to think outside of the box, but, would'nt manipulating the distributor cap not just be a means of bypassing a problem rather than actually fixing the underlying problem? It's my understanding that timing is controlled by the ecu. By modifying the cap you would be doing nothing more than masking the real problem would'nt you?
The ECU is still going to fire the spark when it wants to, so if the cap is turn forward or back, its just going to make the spark jump further reducing its effectiveness at the plug due to a weak spark. You also run into the possibility of cross fires due to ionization in the cap(spark scatter). Thats why caps have a vent, but when the spark is exposed to more air, the more ionization occurs. Not to mention, how many caps is the average joe gonna f-up in the process of slotting the holes..
11-24-2010, 10:18 PM
#26
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instead of creating a spark through grounding through the plugs it fires if its ready or not and will just jump to its shortest distance to ground.. correct?
11-24-2010, 10:20 PM
#27
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No worries, like I said, I was beating my head on the keyboard for two nights trying to make heads and tails on how this system works. In the end I realized its really really stubborn and really set in it ways. Thats why I'm getting rid of it.
11-24-2010, 10:23 PM
#28
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Possibly, but I don't think the stock system put out enough volts to jump to the dizzy body...another reason why I'm going to a duraspark setup...the 65K volt upgrade!
11-24-2010, 10:25 PM
#29
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see this is class now... i get a coil pack type ignition and an electronic distributor type ignition as well dare i say points...this seems to be somewhere between
11-24-2010, 10:41 PM
#30
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