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Discussion Starter · #1 ·
I got to try out the jeep coil yesterday, holy crap!!!!! what a huge improvement! I didnt notice it starting any easier, but the midrange and top end were a alot better! It felt like a cam change, there was that much of an increase in power.
I bought the coil on ebay for 11.50$ I had to drill the mounting holes out to fit a 1/4 bolt, and I used a 90 degree spark plug end (boot) to attach the stock spark plug wire to the coil.
Not sure how the coil would change a stock engine, but with a high comp piston, I think this mod is a must.
 

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Yep! same here with the Dynatek coil but with the same results as you...

greater spark intensity throughout the RPM range, the stock coil craps out above 8000 RPMs the spark color becomes a weak orange...
 

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Yea I agree with a high compression engine the jeep coil or dynatech coil is a must.
 

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Discussion Starter · #5 ·
I did start out with 1 step colder plug, I havnt done a plug check yet.
on ebay, I did a "4.0 jeep coil" search, and found one for 12.99 or best offer. I offered 11.50 and they accepted. i forget the name of the seller.
 

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So with the upgraded coil, do you recommend running a colder spark plug? Or will the stock be fine? Also what is the part number for the coil?

I went down 1degree on the plug when I first did it but once I read my plug I went back up to stock temperature.
 

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Just did a quick search on eBay and noticed that the coil I found has the connector attached still. I know PrityBoy69 did a write up on the upgrade.

TSCRacing did the coil you bought come with the factory connector like this one in the picture.
 

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You can't use that plug unless you change the bracket because it will hit the radiator. What you do it cut that plug off the wires and little metal connectors inside of it. Then plug them on to the pins and fill the hole with epoxy to hold them in place. If you don't have the plug you can do the same with wire connectors.
 

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Yes, spark intensity has nothing to do with spark plug heat range.

Common misconception.

A hotter plug does not have a stronger spark, etc. Heat range is about how much heat the spark plug can transfer from the combustion chamber outside, and for the plugs well being it's ability to stay cool enough not to melt but hot enough not to dry foul.
 

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yes that one would be fine. there is also other high performance coils on jegs that work very well if you are looking for a high output coil.
 

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Discussion Starter · #13 ·
My coil had the 2 spades exposed. I didn't have to do any modifying to them. My stock coil wires slid right on. I looked on e bay, and didn't find the add for the same coil I bought. Mine was a new one though.
 

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I ran a colder plug and used a 40k volt high performance coil. I also made a bracket that would allow me to angle the coil 45* and use the dodge connector. it looks like it came from the factory
 

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Someone should buy a few coils get them completely ready and resell them. They with go fast and cheaper then the aftermarket ones. I have no clue how to mod them and I'm gone but I'd buy one n have it waiting when I get home in Oct
 

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I have no problem building a few coils for people just tell me who needs one.
 
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