1967 427/400 ignition coil

[Thomas S.]

Re: 1967 427/400 ignition coil

Thanks again for your feedback. I did order a coil from Napa that was recommended in a another post on this forum. That will (should) rule out the possibility that the coil is the culprit. I will however post the other detail as a new topic becasue the question remains as to whether the higher resistance readings on the 264 coil are correct.

[Thomas S.]

Re: 1967 427/400 ignition coil

will do - thanks

[Richard M.]

Re: 1967 427/400 ignition coil

Tom, It's possible that the AMA Specs may have coil data. See gm heritage for the information kits.

NOTE Their new URL link to info Kits:

https://www.gm.com/heritage/archive/vehicle-information-kits

Also could you supply us a photo of your 264, top down showing terminals and center contact screw.

The readings you're getting are not far off, so likely not the reason. It may be just a common failure exacerbated by heat, and possibly it may be a reproduction, which could vary quite a bit from original spec and still function fine.

I have used the NAPA UC12/IC12 coils as diagnostic tools which are great replacements for points ignitions. In fact, I've also used them as tools when troubleshooting TI coil issues, with only a high RPM full load possible anomaly. One caveat, the NAPA coils outer diameter is a tad bigger and getting it to fit in the stock coil brackets can be a bit of trouble.

Rich

[Tim G.]

Re: 1967 427/400 ignition coil

That's great information, Richard. Thank you.

[Thomas S.]

Re: 1967 427/400 ignition coil

The AMA did not have the specs.

Photos are below. The coil you mentioned is the one I chose for the same purpose. I was dreading with the tri-power, but bit the bullet. Fuel filters obviously another possibility.
Pictures of the coil below. I also plan on checking the condition of the cap and and points. The cap is not correct so that will be replaced, as will the points and capacitor if they appear to be worn. Wires, are not likely but I do have a set just in case. I know that changing multiple items is contrary to good diagnostic practices but the the cap and rotor are not likely the culprit.




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I couldn't get the good access to the larger nut on the fuel filter flanges so I pulled the carbs and found remnants of black silicone in bronze filter (center and rear carb) that must have been present at some point. Center carb almost completely blocked!

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[Keith B.]

Re: 1967 427/400 ignition coil

repro coils are known to be failure points.

[Patrick B.]

Re: 1967 427/400 ignition coil

Wow, that filter really served its purpose. I am assuming your had fuel issues rather than coil issues.

[Gary B.]

Re: 1967 427/400 ignition coil

[Richard M.]

Re: 1967 427/400 ignition coil

There is one listed on flea-bay currently... https://www.ebay.com/itm/14575021805...&segname=11021

Dave, Good find. That's a reproduction exactly as Tom's coil. Here's the description

1967 Corvette reproduction GM 1115264 ignition coil. Correct for L36 and L68 427 390hp and 400hp engines. Used for a very short time. Coil has some scratches due to the coil mount bracket. coil is dated 09/04 on the bottom. Fully functional. Shipping within the US only.
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Tom, That repro is in the category of "serious suspect". All of those repro coils are internally identical, but just different can numbers applied. We've had the identical issues with all repro TI coils. Built the same internally with the different can numbers. These were made overseas with no temperature tests, i.e. no burn-in".

These are prone to fail at temp, in fact, they self heat and can exceed 250* F, which I've proven on a L71, with TWO, YES TWO repro 263's. BOTH were bad at normaized engine temperature. This anomaly sent me in the directions of other distracted fault diagnosis, as you can imagine.

I finally put in that NAPA coil, per Dave Fiedler's recommendation. That engine ran great for a summer until I found a NOS 207 Service coil.

That filter needs attention too but I think the miss problem is that coil.

Rich

[Thomas S.]

Re: 1967 427/400 ignition coil

So are you saying my coil is a repro or the the one ebay, or both? I was aware that these coils are coming in from China, but with my date code I figure I was good. In any event, I put "Humpty Dumpty" back together. The Napa coil center post contact did not like the corresponding new wire from ElectricLimited. I think my wire set is original based on the printing compared to the new set. It's too bad there are no other sources for dated wires.

To be continued.

[Keith B.]

Re: 1967 427/400 ignition coil

Yours is a repro and so is the one on the ebay ad. If you bothered to read one of my last post I told you the 264 was NEVER avalible over the counter at your Chevy parts dept. if you needed one they would have sold you a 202. And that is what I suggest you buy. Not a repro one. A real original used one or a NOS one

[Thomas S.]

Re: 1967 427/400 ignition coil

I did read it but missed the part about the 264 not being available over the counter (Chevy parts). Found a NOS 202 in sealed Delco Remy box (pull string.

Thanks again.

[Thomas S.]

Re: 1967 427/400 ignition coil

So far so good with the NAPA coil. Will run it this way for a few days.

thanks again.

[Thomas S.]

Re: 1967 427/400 ignition coil

So far so good with the NAPA coil. Will run it this way for a few days.

thanks again.