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I just saw a Ford Distributor cap and coil on a CJ...he told me it was a common conversion that fits the factory distributor.

Please tell me where to find out what parts I need.
 

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I don't have the PNs handy, but there's the AMC distributors are all Ford tops.

There's an adapter that mates the smaller diameter circle of the distributor to the larger cap. Then you'll need the cap and rotor.

If you've got a 258, get the cap/rotor for a 300 I-6, if you've got a V8, get the cap/rotor for the 460 gas engine. Either way, tell the parts monkey you need the adapter to fit the cap to the distributor - they should be able to find it in their computer.
 

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If you go to the Off-Road.com swb Jeep bbs and search for "TR Upgrade" you will find about a thousand posts or so about this conversion, including how to troubleshoot it and the issues commonly seen with the conversion. Done right, it beats the HEI hands down.
 

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mo I am your bitch now thank you that will be all ....................any ways I prefer that swap I have just seen it in action and it works very well...............ltr

edit, that kit is about the same price as the one I posted thanks maine jeeperah


here is a tfi write up
 

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Read the link Maine Jeepha posted, it expains the benifits to the TFI conversion. Doesn't seal any better than stock.
 

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jeepinblackdog said:
Does this mod/upgrade seal better than the OEM and what is the advantage of upgrade other than being able to run a hotter coil?
Hotter spark=better, more efficient running Jeep.:D
 

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jeepinblackdog said:
Does this mod/upgrade seal better than the OEM and what is the advantage of upgrade other than being able to run a hotter coil?
No, actually it gives you an extra area where water can get inside. I sealed my wires and caps with some dielectric grease.

Hotter Coil makes for a better spark with a wider gap. The gap in the spark plug effects the ability of the spark to ignight the mixture in the cylinder. The longer the gap the more of the mixture comes in contact with the spark. This help to prevent misfires especially under lean mixture conditions. As you know if you run a leaner mixture the better your gas miliage will be. The limiting factor in the spark plug gap is of course the voltage needed to jump the gas. The TFI bumps the voltage up considerably. You can see here you have to run a much larger distributor cap than in the stock ignition system and much thicker insulated spark plug wires to prevent arc over.

Conversly a to small of gap may delay (the experts say) the firing of the mixture leading to incomplete combustion, fouling plugs, wasting gas, etc. so you can start to see how spark gap, timing mixture plays an inportant part in how well your engine runs.

Bigger gap is good but sometimes there are other conditions that can effect how big the gap can be. When the plug is cold there is a possibility of gas collecting on the insulator forming an ohmic resistance path that can drain away energy needed to fire the plug when cold.
A spark plug has to reach 400º to burn off any deposits that it may collect. This is why we have to select the correct heat range for the plug. Until this temperature is reached a plug may misfire while cold so you will have to adjust the gap smaller so the spark can jump. So you can see where making sure you have the correct mixture is also important in determining the correct gap for your needs.

At 14:1 mixture you only need 0.2mJ to ignight a mixture. Going to 12:1 like when you accelerate or under power or 10:1 with a vacuum leak you need 3mJ. So you say "My Coil puts out about 120 mJ when firing, whats the problem?" Well there is length and construction of the spark plug wire, condition of the distributor cap, etc. Thats why some people find they need to adjust the gap differently for different cylinders. The mixture distribution in a 258 intake manifold is horrible because of the intake design. So you might have to adjust the gap diffently in different cylinders. Maybe a smaller gap where the mixture is to rich that will effect cold engine operation.

I may be good to learn how to do a plug cut and learn to "read" a plug. You might need to go to a little hotter plug to burn off deposits on the plug.

Welcome to the plug brand, construction, gap, and heat range game. Throw in a little timing error and incorrect jet sizes and your in for a headache in search of the perfect combination. At least you'll have enough spark to cover different plug test.
 
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