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post #11 of (permalink) Old 09-05-2003, 05:14 PM
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Re: tfi problems on a 258

I've been running the TFI setup on my CJ for 2 years now with no parts replacement. I have not added or removed any resistor wire. Someone please clarify this.
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post #12 of (permalink) Old 09-05-2003, 09:40 PM
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Re: tfi problems on a 258

The "TR" upgrade as usually presented is only a halfway solution. As noted the TFI coil was designed to have 12V. To get 100% "TFI": 1) Remove (route around if you feel the need to keep) the resistance wire, and 2) grab a DuraSpark II module from a salvage yard with the connectors (squared instead of rounded like regular Duraspark) and splice it in place. The wiring goes the same way only the connectors are different. The DuraSpark II module was designed to have 12V continuous so they should not have reliability problems like the older version. Many people say they run the stock module with the full 12V without problems though. It may only be aftermarket modules that fail, who knows, but going DuraSpark II is cheap and easy so why not. Note it's also possible to use a GM HEI module in place of the DuraSpark II with a little more wiring and mounting issues to deal with.
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post #13 of (permalink) Old 09-05-2003, 09:49 PM
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Re: tfi problems on a 258

well one of the problems is that the diagram for the tfi upgrade has the coil wires reversed, which caused the resistance wire to get so hot that when it cooled down it was brittle. maybe cooked the tfi coil too. from what i've read you can run the tfi coil at 12 volts. it was the old canister coil that had to run at 9v. i will probably get the ignition box to go with the tfi setup.

thanks for the help everyone,

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post #14 of (permalink) Old 09-06-2003, 03:02 AM
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Re: tfi problems on a 258

I could be all wrong here, so correct me if so... But I had the prestolite garbage setup atop my 304 and did the tfi upgrade. My stock setup had 12V going to the coil, and I had to add the ceramic resistor to give the TFI coil 9V or so. I was always under the impression the TFI needed lower voltage than the prestolite setup....
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post #15 of (permalink) Old 09-06-2003, 09:13 AM
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Re: tfi problems on a 258

OK, Now I'm confused.

LEVE and WILL both say 8-9V.

RRich says the coil is designed for 12V.

Most agree that 12V slags Duraspark I modules, but I don't see how the resistor in the attached diagram affects the voltage to the module. (someone please throw up the diagram, i don't have a pic site)

Is there a cabal of capital-letter-handled pooh-bahs trying to handicap my 258's performance, or are they the prudent ones?
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File Type: jpg 1182078-Duraspark with tfi.jpg (43.1 KB, 4 views)
post #16 of (permalink) Old 09-09-2003, 08:51 PM
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Re: tfi problems on a 258

anyone still following thisun?
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