Coil Part Number Succession - 1115287

[Ken A.]

Re: Coil Part Number Succession - 1115287

You won't be riding in anything newer than a C-3, if you remove the all the off shore parts.

[Mark E.]

Re: Coil Part Number Succession - 1115287

In a search for a replacement coil, I researched several sources. The table below shows the factory specs for primary and secondary resistance, and specs for several replacements. So far, the AC Delco U505 is the only one within spec, albeit it's oil rather than epoxy filled.

I called Standard Motors and asked why all of their coils are out of spec for the intended application (most pre-HEI Chevy v8s). They didn't know.

Does anyone know the effect of primary winding impedance being lower than spec?

Source	Brand	Model	Pri Ohms	Sec k Ohms	$
Factory Spec			1.77 - 2.05	3 - 20
Amazon	ACDelco	U505	2	10	35	Oil	Black
NAPA	Echlin	IC676	1.3 - 1.5	13 - 16	53	Epoxy	Black
	Echlin	IC12	1.3 - 1.5	7.7 - 9.5	38	Oil	Black
	Echlin	ICI1600	1.3 - 1.5	6.5 - 8	88	Oil	Chrome/Tan
	Accel	8140C	1.4	9.2	42	Oil	Chrome/Black
	MSD	8202	0.7	4.5	45		Red/Black
Summit	Std Motor Blue Streak	UC12X	1.3 -1.5	7.7 - 9.5	36	Oil	Blue
	MSD Street Fire	5524	0.35	7.8	32	Epoxy	Black
	Mallory	29217	1.4	10	34	Oil	Chrome/Black
Jegs	Jegs	40105			27		Red/Black
	Jegs	40100	1.5		30		Chrome/Black
	Accel 8140C	8140C	1.4	9.2	32	Oil	Chrome/Black
	MSD 8202	8202	0.7	4.5	48		Red/Black
Paragon	Reproduction				140
JC Whitney	Accel	8140HV	0.6	9.5	54	Epoxy	Black

EDIT: Added specs for Echlin

[Ken A.]

Re: Coil Part Number Succession - 1115287

Actually, the oil is an insulator to keep the 2 coils in the can from shorting. Over time, carbon tracks appear in the oil causing the coil to short & collapse under load. That is why a used coil may check "good" off the car, but fail under load. A used 40 year old coil is a paper weight, or for a trailer queen. Original coils were vacuum filled thru the tower. You do not want to hear any slosh.

[Floyd B.]

Re: Coil Part Number Succession - 1115287

I'm confused - AGAIN.

I was about to buy a U505 but when I looked this up on the AC Delco site I noticed that it clearly states this coil requires an external resistor if it is used with points. The Delco site indicates that the proper replacement for an LM (427/390 mt) or LL (427/390 at) is E552C. Can someone clear up this confusion for me?

Thanx

[Ken A.]

Re: Coil Part Number Succession - 1115287

ALL points type V-8 coils require an external resistor.

[Joe L.]

Re: Coil Part Number Succession - 1115287

I'm confused - AGAIN.

I was about to buy a U505 but when I looked this up on the AC Delco site I noticed that it clearly states this coil requires an external resistor if it is used with points. The Delco site indicates that the proper replacement for an LM (427/390 mt) or LL (427/390 at) is E552C. Can someone clear up this confusion for me?

Thanx

Floyd------

All 1957-74 Corvettes have an external resistor, except TI. The 1957-67 use "ceramic block" type resistor mounted to the firewall. 1968-74 Corvettes use a resistance wire which serves the same function.

The Delco U-505, aka GM #12337166, is the "direct descendant" of the original coil. This is supposed to be an OEM quality component.

The Delco E552C, aka GM #89057911, is an aftermarket quality coil of the Delco "Professional" series. You can definitely use it for your application if you wish. It's even several dollars less expensive.

[Ken A.]

Re: Coil Part Number Succession - 1115287

Joe,
You are misinformed re: TI coils. They use the resistance wire to drop the voltage around 7 volts, which is lower than ceramic block type of coil, not that it makes any difference to Floyd's question.
Ken

[Floyd B.]

Re: Coil Part Number Succession - 1115287

What does the "B-R" embossed on 287 coils mean?

Thanx

[Mark E.]

Re: Coil Part Number Succession - 1115287

What does the "B-R" embossed on 287 coils mean?

Thanx

Ballast resistor. My guess is Delco embossed the last three digits of the PN and B-R so all those black canister coils in the factory could be easily identified.

[Floyd B.]

Re: Coil Part Number Succession - 1115287

I just received an E552C (GM# 89057911) Made in Mexico. It is liquid filled.

[Mark E.]

Re: Coil Part Number Succession - 1115287

Here's a comparison of some coils I gathered for my '70 LS5. See post 17 for more specs.

Original AC 1115287 from my '70 LS5- Second from left in photos for comparison. Epoxy filled.

AC Professional E552C service replacement- Third from left in photos. Box says made in Mexico. Compared to the AC 287, it's physically shorter with a bit taller secondary wire tower, and its top shoulder looks significantly different. Oil filled; sloshes a little.

Echlin IC676- Far right in photos. Physically the shortest, yet with the tallest secondary wire tower. The appearance of the top shoulder is close to the AC 287, with raised pads for the primary connections shaped like the original. Made in USA. Even though it looks a lot different than the original, I kept it because it's one of the few epoxy (vs. oil filled) replacement coils I found. At $53 NAPA list price, it's the most expensive coil of the bunch (but I did get a 30% discount ).

Jacobs 380672- Far left in photos. This was lying around the garage. Jacobs was acquired by Accel (I think) a few years ago, which is now a Holley brand. I believe the Jacobs brand was dropped so I doubt this coil is currently available. I don't know its specs; unknown country of origin. Compared to the AC 287, it's physically shorter with a taller secondary wire tower that sport ribs, and its top shoulder looks significantly different. Chrome body. Oil filled (but sloshes very little).

AC U505 service replacement- Not pictured. Purchased but already returned it. As I recall, it looked similar to the E552C but sloshed more (oil filled).

Accel 8140- Not pictured (it's on the car). Physically very close to original AC 287 but a bit taller secondary wire tower and the body is chrome (I believe yellow is also available). The appearance of the top shoulder is very close to the original, including the shape of the raised pads for the primary connections. Made in China. Oil filled; sloshes a little.

They're all about 0.026" greater in diameter than the AC 287 (isn't that odd?), but fit fine using the stock bracket and mounting screw (unlike some of the reproduction coils I've hear about that are too big for the screw to fit).

The only two I've actually used are the original AC 287 and the Accel. Each works fine with LS5's stock points ignition, although I've only logged 20 miles with the Accel.