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Old 12-11-2009, 06:28 AM   #354
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Originally Posted by 03OrangeSVT View Post
I've decided to make an "ignition" thread.

and post up answer's to the more commonly asked questions.

Do I need to upgrade my coil?

Simply put.... No
Stock coils will provide enough spark to support over 700whp. The average 4 tower coil will put out between 36-40k volts most aftermarket coils put out only 42k MAX. You will not see any gains what so ever by swapping out a working stock coil for an aftermarket one.

Do I need to go with those really expensive plugs?

Again.... No

Unless you have a HEAVILY Modded (MORE THAN BOLT ONS) engine there is no need to use any other plug than STOCK. You CAN re-gap the stock plugs to .060 (in most cases) and you will get a smoother idle and the overall running of the car will be improved... but just slightly. When you open up the gap it take MORE voltage to jump the gap and make spark.. therefore wider the gap the hotter the spark.

Now if you are running Nitrous of Forced Induction then yes you can benefit from changing plugs. I highly recommend the MotorCraft AZFS22C f4 sparkplugs. They are copper cored (which is one of the BEST conductors of electricity.. better than Iridium) and will provide a wider,stronger spark. They also work VERY well with NA engines,and at $8 a set you cant go wrong.

Should I change plug wires?


Changing your plugs wires is problely the most effective ignition upgrade you can do on a Focus. Any descent low resistance wire is MILES beyond the stock wires... I can not say how much I despise stock wires for there inability to carry good voltage. Remember the bigger the wire the better... smaller wires will heat up internally and heat greatly reduces their ability to conduct electricity.

Well thats your basic ignition questions covered... feel free to ask any questions that you have.

and I quote the first post
[B]1951 McCormick FARMALL M
2007 MINI Cooper S Turbo... new project car
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2004 Harley V-Rod.... sex on wheels
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