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From $154.75 to $253.00
Engine/Magneto Part No. Price Buy
Cont. A-65/S4 12301-02 $171.00
C-85/S4, 0-200/S4 12301-05 $189.00
C-90/S4 12301-06 $162.95
Lyc. 0-100/S4, 0-235/S4, 0-290/S4 12301-21 $164.95
0-320/S4, 0-360/S4 12301-22 $173.75
Cont. A-65/SF4 12302-02 $154.75
A-75/SF4 12302-03 $157.75
Lyc. 0-100/SF4, 0-235/SF4, 0-290/SF4 12302-20 $187.75
Cont. E-185/S6 12305-10 $230.95
E-225/S6 12305-11 $251.95
O-470/S6 12305-13 $206.95
C-145/S6, O-300/S6 12305-09 $229.95
Lyc. 0-540/S6, IO-540/S6 12305-22 $253.00
Franklin 165/S6 12305-41 $222.95
Cont. C-125-SF6 12307-08 $228.95
Lyc. 0-435/SF6 12307-23 $251.95
Subtotal $0.00
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Note: Photo is for reference only. Individual items may differ.

Production ignition harnesses at remarkably low prices. Late type 5MM wire constructed of 16 strands of tightly braided copper wire impregnated with scuff resistant white silicone. All strands must fracture before a complete open circuit type failure occurs thus extending lead life. Lead flexibility is retained from -65 to 400F. Moisture & cleaning solvent penetration is eliminated by the impregnated silicone coating.

This extremely flexible wire lends itself to sharp bends thereby eliminating the need for old style harness elbows. No soldered joints in the grounding circuit. Custom made for most 4 & 6 cylinder engines using Bendix or Eisemann magnetos and 4 cylinder engines using Slick magnetos.Cable outlet plates are not furnished for Bendix & Eisemann mags as these are already installed on the magnetos in service. They must be purchased separately for new magneto installations. Harnesses for Slick magnetos are furnished with the backplates installed. Standard harnesses for the Bendix S4/S6 mags are fitted with a male nut which screws into the threaded outlet plate on the back of the mag. Harnesses for old style Bendix SF4 and SF6 magnetos are fitted with female nuts.

ACS Products ignition harnesses can be used on experimental aircraft or on certified aircraft with field approval (FAA Form 337). If FAA/PMA harness is mandatory or if for use with 3/4" spark plugs, use Slick Bendix, Aero-Lite or Champion harnesses.
Made in USA

Replacement Leads

Replacement Leads For Bendix & Eisemann

Description Part Number Price Buy
Replacement Leads to 48" (Specify Length) (Bendix & Eisemann only) Call for pricing

All Harnesses Furnished with Cable Ties and Clamps
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Nice harness, well made.

Jeffrey M
November 9, 2019

Garry L
August 14, 2018

They look pretty good and should work but I only needed half of them since I have half an EI system.

March 2, 2019

Perfect on the lower cylinders. An inch longer on the top leads what have been 5 stars

Will M
June 29, 2017

Leads are a little short for an O-320. Had to buy a second set & replace a couple with longer leads due to the bend radius on a couple cylinders looking like they were kinked over which wouldnt last.

Flyboyz A
September 5, 2018

Ordered as advertised for my 029D. 4 lines fit normally. 2 lines were a bit snug. 2 longest lines did not fit(2-3 in short) and will have to be replaced. Very frustrating and costly. Not recommended for 0290D.

December 27, 2018

Some wires are very short especially for bottom of cylinder #1. Could not root them nicely. Also one easily pulled out of the end that went into the Mag. Someone was able to help me reinstall it so not too much of a problem. Read the comment from a previous person re short wires so thought that the company might of fixed the problem but they have not. Perhaps ordering the size for bigger engine might fix the problem of short wires but not sure. Also could not drill hole in side cutter to use as crimper as suggested so had to use die grinder to do so.

November 1, 2018

This is a very hard product to use. None of the wires are marked so if you pick wrong then you need another wire. Plus after you have oriented the wires to their respective position there is not enough wire for 1 & 3 cylinder bottom or 2 & 4 cylinder bottom. Left and right mag respectively. Plus dont even call the manufacture, they are no help and Aircraft Spruce is so busy it take a couple of days for them to get back with an email asking if you still have a problem. Not a happy installation.

Gerald C
April 22, 2019

Only fits harness caps that already have THREADED holes for existing leads on TCM/Bendix/Eismann harness caps. IF YOUR HARNESS LEADS ARE SWAGED INTO YOUR HARNESS CAP WITH TAPERED FERRULES THIS HARNESS WILL NOT WORK.

Scott N
March 21, 2018

For O470 the description is not adequate. These do not fit my O470R model engine.

Russ E
November 20, 2017


Q: Does the 12305-11 set have 90 degree ends at the plugs? Also, can you confirm this is the proper set for an A35 bonanza with E 225 engine.

The ACS Products harnesses do not have 90* elbows, and are not FAA approved. Intended for use on experimental aircraft only.

Q: Regarding the shielded ignition harnesses for Bendix mags: Are the prices quoted for magneto harnesses per magneto or per engine?

These are priced and sold per engine. You will get a left and right harness.

Q: I am in need of a complete harness assembly including the rear distributor box for a Bendix S6lN-21 mag for my Continental 145-2. Do these ACS harnesses come with the rear block or do I have to make the ends up to fit?

ACS harnesses are made to be used with 5/8" barrel spark plugs, and the magneto cap is not included for Bendix mags, they hare threaded leads. The harnesses for Slick mags have the magneto plate swaged to the harness leads.

Q: These leads are advertised as suitable for use on a certified engine so long as a form 337 is filed... do these leads come with the proper reference data to file with the 337?

The units do not come with the documents for a 337. The aircraft owner will need to discuss the approval process with the A&P and possibly work with the manufucaturer for specific details.

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