091 coil

[Tim T.]

How do you test an original 091 coil (for 63 SHP) ? And what values should it have?
Thanks in advance,
Tim

[Dave S.]

Re: 091 coil

How do you test an original 091 coil (for 63 SHP) ? And what values should it have?
Thanks in advance,
Tim

Put in your car with the shielding installed and run it for 15 or 20 minutes so it gets good and hot.

[Richard M.]

Re: 091 coil

I agree with Dave. You can test with a ohmmeter for basic functionality. You should get a few ohms plus to minus, and a few more coil output to minus, but the real test is to get it good and hot under normal driving conditions to verify it's true functionality.

Rich

[John D.]

Re: 091 coil

How do you test an original 091 coil (for 63 SHP) ? And what values should it have?
Thanks in advance,
Tim

Tim, 63 Shop manual. Specifications 14-5.
Also the Corvette Servicing Guide ST 12 manual has the values for the '091 coil.

Primary Resistance-Ohms 1.02-1.13
Secondary Resistance-Ohms 8000-10,500

Then check to see your have the correct Ballast resistor. D1111 1.4-1.62

[Duke W.]

Re: 091 coil

'63 SHP/FI engines used the 0.3 ohm ballast with the 091 coil, but the higher resistance ballast will work okay and is easier on the points due to less primary current, which means less ignition energy, but with unleaded fuel and AC heat range 5 or equivalent spark plugs, you'll never know the difference.

Duke

[Richard M.]

Re: 091 coil

Wasn't there a TSB for the '63's telling the service folks to change it to the higher ohms ballast.

........just found it in the JG.

P1010062.jpg P1010063.jpg

[Tim T.]

Re: 091 coil

John,
Thanks, that is what I was looking for, just didn't look far enough in the Shop manual. But what is the Corvette Servicing Guide ST 12 & where can I obtain one?

Duke,
Thanks again, That is what I was planning. By the way, the engine I had built to your recommendations is fantastic, revs freely.

Thanks to all,
Tim

[John D.]

Re: 091 coil

Tim, THe Corvette Servicing guide has my favorite FI manual tucked inside.
Seems the shop manuals showed progressive info and the writers left out into in the later manuals because they already had it in earlier manual. May not make sense the way I said it but the prove is this. Say you own a midyear FI car. Then you really need to own The Corvette Servicing guide as it has FI info not contained in the poorly written 63 FI section.

Meanwhile Tim you can purchase from NCRS. John

Just looked Tim, $28.95 in the store.