Page 1 of 6 123 ... LastLast
Results 1 to 10 of 57

Thread: CMC legal coil question

  1. #1

    CMC legal coil question

    Hey guys, I'm posting my question here cause it will get more views/opinions and solutions vs the national forum

    Anyway, our CMC legal coil is in need of being replaced (Fox Mustang). We have a MSD Ignition Blaster TFI (part number 8227) that came with the car many years ago. We were told (I think) that it isnt a legal coil so we removed it.

    We were looking at purchasing a Accel Supercoil Ignition Coil to match our soon to be purchased cap and rotor in preparation for west coast Nationals. Accel states "These are direct plug replacements for OEM coils."

    https://www.oreillyauto.com/detail/a...=ignition+coil

    Since they fall within exactly the same resistance test specs as the OEM coil, and only a "longevity" advantage due to the "premium materials" used in the construction. Accel claims there is a higher voltage spark that lends to quicker starts and better combustion spark at high RPM that leads to better performance, but I also ran across a voltage vs. current discussion that may indicate a higher voltage isn't really an advantage like a higher current or energy is, so a higher voltage may just be advertising hogwash to sell more product.

    We'll likely be running ST4 at Nationals since there are no CMC cars currently signed up (except us) for CMC. I'm sure the coil doesnt matter in ST4 but I'd like whatever I get to be legal for CMC.
    Last edited by BADVENM; 09-07-2017 at 04:21 PM.

  2. #2
    Senior Member Site AdminCarroll Shelby michaelmosty's Avatar
    Join Date
    Mar 2006
    Location
    Dallas, TX
    Posts
    2,837
    Not CMC legal. It is a slippery slope of where do you draw the line from original to various aftermarket products that might give an advantage so in this case original replacement is what is needed.
    -Michael Mosty
    CMC #11 Mosty Brothers' Racing
    Director - TX Region

  3. #3
    Junior Member Rookie MHISSTC's Avatar
    Join Date
    Jul 2008
    Location
    Goodland, KS
    Posts
    26
    Please indulge me asking a few more questions because I want to understand the reasoning behind the illegal declaration and how we should move forward from here.

    * What is the basis for the Accel coil being illegal when Accel states it is a "direct plug replacements for OEM coils"?
    * What advantage "might" this coil give?
    * Everywhere I checked the Accel coil is cheaper than the OEM Motorcraft DG470 unit with a Ford part number, although not quite as cheap as the various store brands like Valucraft, Duralast, MileagePlus, and MasterPro.
    * Of the specs listed about the coil, the resistance falls well within the ranges specified in the service manuals.
    * Other than looking for bright yellow Accel or bright red MSD, or looking for coils that obviously don't conform to the OEM form factor, how in the world are the tech folks going to go about testing/checking for illegal coils?
    * How are we going to prove we HAVE an OEM replacement coil?
    * Are we going to need to specify a "spec" coil within the rules that indicates a sticker with Ford part number F7PJ-12029-AA needs to be present with all other coils besides that one being considered illegal?

  4. #4
    Junior Member Rookie MHISSTC's Avatar
    Join Date
    Jul 2008
    Location
    Goodland, KS
    Posts
    26
    Additionally, Accel sells a couple different versions of their cap and rotor.
    The first version is labeled as their "Heavy Duty" version that are gray in color with brass inserts.
    The second version is labeled as their "High Performance" version that are tan in color also with brass inserts. This is the one we've had on the car for the better part of a decade.

    So now I have more questions:
    *Are the tan Accel cap and rotor we currently have installed also illegal because the are labeled as their "High Performance" versions?
    *Are even the gray "Heavy Duty" labeled Accel cap and rotor also illegal because they also have brass inserts while other "OEM replacement" cap and rotors under the Duralast, Valuecraft, MasterPro, and even the Motorcraft versions do not have brass inserts?

  5. #5
    Senior Member Site AdminCarroll Shelby michaelmosty's Avatar
    Join Date
    Mar 2006
    Location
    Dallas, TX
    Posts
    2,837
    Quote Originally Posted by MHISSTC View Post
    Please indulge me asking a few more questions because I want to understand the reasoning behind the illegal declaration and how we should move forward from here.

    * What is the basis for the Accel coil being illegal when Accel states it is a "direct plug replacements for OEM coils"?
    * What advantage "might" this coil give?
    * Everywhere I checked the Accel coil is cheaper than the OEM Motorcraft DG470 unit with a Ford part number, although not quite as cheap as the various store brands like Valucraft, Duralast, MileagePlus, and MasterPro.
    * Of the specs listed about the coil, the resistance falls well within the ranges specified in the service manuals.
    * Other than looking for bright yellow Accel or bright red MSD, or looking for coils that obviously don't conform to the OEM form factor, how in the world are the tech folks going to go about testing/checking for illegal coils?
    * How are we going to prove we HAVE an OEM replacement coil?
    * Are we going to need to specify a "spec" coil within the rules that indicates a sticker with Ford part number F7PJ-12029-AA needs to be present with all other coils besides that one being considered illegal?
    -I haven't researched specs on stock ignition parts vs aftermarket parts so I can't talk about any advantages these parts "might" have. The rules reasoning is to not allow that slippery slope to be there for any perceived advantage and state the part must be of OE spec.
    -There are tons of "direct plug replacement" parts and "direct bolt in" parts for the car that give far more performance than their OE part.
    -It doesn't matter that the part is cheaper.
    -Regarding tech, the obvious part is to look for the yellow or red coil / cap / etc. If there is any question on the legality of the part it will be further researched / discussed.
    -Not sure what you mean by "Having" to prove an OEM replacement coil. Do you "have" to prove other parts on your car are legal?
    -We are not going to specify a "spec" coil and you don't have to run a Ford part number coil. Currently the rule will stay as is but since we are getting near the silly season you are welcome to submit a RCR if you wish.
    -Yes, if your current cap / rotor has brass inserts then they are illegal.

    The intention of the rule is stock replacement parts. Your note about Accel: Accel claims there is a higher voltage spark that lends to quicker starts and better combustion spark at high RPM that leads to better performance, but I also ran across a voltage vs. current discussion that may indicate a higher voltage isn't really an advantage like a higher current or energy is, so a higher voltage may just be advertising hogwash to sell more product.
    They specifically claim "better performance" so there is no way this will be allowed.
    -Michael Mosty
    CMC #11 Mosty Brothers' Racing
    Director - TX Region

  6. #6
    Senior Member Carroll Shelby Supercharged111's Avatar
    Join Date
    Jun 2014
    Location
    Colorado Springs, CO
    Posts
    1,149
    In my experience factory ignition components tend to be better made and outlast aftermarket stuff. For that reason I bought all AC Delco and Delphi ignition parts for my Camaro. I've used aftermarket coils and ICMs in the past and the experience was so bad I won't go back. Accel doesn't make very good parts IMO. Why else do you think they're so cheap? What's wrong with the current coil?
    RM CMC Director

  7. #7
    Senior Member Carroll Shelby Fbody383's Avatar
    Join Date
    Aug 2006
    Location
    Pearland, TX
    Posts
    3,269
    Rule is outdated. Change the rule, run any coil you want and specify it on the dyno sheet.

    It does matter that it's cheaper which is supposed to be a facet of this series.

    Not sure why $2500 brakes are cool but a coil isn't.

    It's time to have serious discussions overall about what this series is about.
    #39 CMC Camaro
    Orange is Fast!
    CMC-NT01 FTW!

  8. #8
    Senior Member Site AdminCarroll Shelby michaelmosty's Avatar
    Join Date
    Mar 2006
    Location
    Dallas, TX
    Posts
    2,837
    You could look at every single part we run on our cars under a microscope and say how some rules make sense and some don't. Bottom line, why would you want to run an aftermarket part? Specifically a coil, distributor cap, or rotor.

    If it is for a performance advantage, then that is why the rule is written that way. If it is for reliability, then submit an RCR.
    -Michael Mosty
    CMC #11 Mosty Brothers' Racing
    Director - TX Region

  9. #9
    Junior Member Rookie MHISSTC's Avatar
    Join Date
    Jul 2008
    Location
    Goodland, KS
    Posts
    26
    I appreciate the discussion.

    The whole reason this came up for us in the first place is that we have what seems to be an intermittent spark issue. It's been odd to try and track down, because I would have said it was a throttle position sensor problem, but the sensor checked out just fine previously. At idle everything is good and the engine runs smooth. At full throttle, we have full power. During a race, we have an intermittent condition during throttle tip-in where the engine doesn't quit, but it sort of stumbles or misses and only produces partial power. A split second after the accelerator reaches the floor *BAM* you have full power again. It's a crappy thing to deal with as it can be unexpected and lead to some power induced oversteer on corner exit when the throttle acts like an intermittent on/off switch.

    Dave had a qualifying race last weekend where the condition was NOT intermittent and any accelerator depression much above idle led to a continuous severe stumble that didn't clear up at full throttle. We previously had an issue where the spout jumper wire was grounding out on the alternator bracket. This wasn't that, but in desperation Dave wiggled all the ignition wires, harness, and pulled off and replaced all the plug and coil wires. Things were magically *fixed* after that with no good explanation of why.

    In the process of *fixing* things, we did notice the little male connector end on the coil where the coil wire from the distributor cap connects to the coil was loose. The connector wasn't a screw-on type, so it couldn't be tightened. We don't think this was the cause of our issue, but it surely didn't help. That's when we started discussing the replacement of our coil and possibly other components in our ignition system that are several years old. This includes the 30+ year old factory wiring harness and connectors that lead to the TFI module and coil. I suspect something in the OEM harness may actually be where our problem is originating. At the very least, we'll be replacing the connectors to those components that are available with wiring pigtails along with any other wires that appear to be of sketchy condition.

    The discussion of what to replace the older components with led us to a discussion of what would be considered legal and where our current stuff stands with regard to legality after using it for nearly a decade.

    It appears, as the rules are currently written, while any plugs and wires may be used (some of which surely have a performance benefit), the cap and rotor with brass inserts we've used for nearly a decade are actually illegal. I think we may need to request a rules revision here as I'm not sure there is any "performance" benefit with our current cap and rotor, but instead more of a "reliability" and "longevity" benefit as those components still look like they are in pretty decent shape for never having been changed the whole time we've run the car. Wouldn't any performance gain realized by a mild performance coil be accounted for on the dyno and similarly be more in the realm of reliability and longevity by potentially being constructed of higher quality base components? I actually have no problem with any coil folks choose if it remains in the same form factor as the OEM coil. Basically, I think anyone should be able to use any coil that is the same size and shape as the OEM coil, not just the same output as the OEM coil. Nearly every OEM replacement and cheap mild performance coil fits that requirement. Only the seriously hot, huge, and very expensive racing coils would be excluded. I've actually tried to find out what the output specifications of the OEM coil are, but I haven't been able to find them listed anywhere, and I have no idea how to go about testing that. The only specs I have found with regard to the OEM coils are the resistance values of the windings. The Accel coil we were looking at meets those values. Accel also publishes their coil output values, but without any OEM values to compare them to, I actually have no idea how much, or even IF those values are any different. My gut feeling is if they are different, they aren't by very much. But without the OEM values to compare it to, I have no idea.

    Here is another possible request for a rules change I've had on my mind for years. How about allowing the relocation of the TFI module from the distributor to a remote location on a fender well with a heat sink. This would remove it from a very hot location that can lead to it's degradation thereby increasing it's longevity and reliability by keeping it cooler with no gain in actual performance.

    So, in the mean time, I guess we all now know what we can protest on our competitors cars at the Championship Events this year that actually have a field of CMC cars. Have the tech inspectors check the Fords for non-OEM replacement coils along with coils, caps, and rotors with brass components instead of whatever silver colored metal Motorcraft uses in their OEM components.
    Last edited by MHISSTC; 09-08-2017 at 06:40 PM.

  10. #10
    Senior Member Carroll Shelby
    Join Date
    May 2013
    Location
    Arlington, TX
    Posts
    1,017
    Hands-down the most reliable ignition set up I've ever used is OEM, every aftermarket ignition system I've dealt with has been problematic
    Tyler Gardner
    CMC #13 2015-2017
    SM #013 2018
    www.dfwmustangs.net

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •