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Electronic Ignition

Mon Oct 08, 2012 11:52 am

Hello to all
Any information as to pros & cons on the electronic ignition for the Cubs?
Thinking about installing this to get the extra power for the hills on the farm. Does this actually add an additionl 8 to 15% power?
Seems easy enough to install but as always research,research,research!!!!!

Re: Electronic Ignition

Mon Oct 08, 2012 11:59 am

Yes it does increase hp. My loboy starts easier and runs much smoother than before. I will be installing another one on my 71 model soon.

I got mine from Brillman in Virginia for around 80 bucks. Good investment.

Re: Electronic Ignition

Mon Oct 08, 2012 12:30 pm

Electronic ignition has been discussed several times on this board. Search function.

If you install an electronic ignition, save all of your points ignition parts. You will need them, when/if, the electronic ignition fails.

Re: Electronic Ignition

Mon Oct 08, 2012 3:47 pm

Tezell wrote:Yes it does increase hp. My loboy starts easier and runs much smoother than before. I will be installing another one on my 71 model soon.

I got mine from Brillman in Virginia for around 80 bucks. Good investment.



Sounds good. The one I was looking at is $112.00

Re: Electronic Ignition

Mon Oct 08, 2012 3:56 pm

Just remember to re-gapp the plugs to .035 for best performance. You should not expect quite that much power gain, 3 to 5 would be more realistic. But they run and start better. Bill. wlm cub

Re: Electronic Ignition

Mon Oct 08, 2012 4:46 pm

$112 Vs. >$20 OEM? what am I missing?

Re: Electronic Ignition

Mon Oct 08, 2012 5:23 pm

WLM Cub wrote:You should not expect quite that much power gain, 3 to 5 would be more realistic.
Assuming that Bill's 3% to 5% gain is correct. For easy math let's assume 10 hp on the draw bar with an engine in excellent condition.

10 X .03 = 3/10th hp increase at the engine, bit less on the draw bar. 10 x .05 = 1/2 hp increase at the engine, bit less on the draw bar. A full tune up will increase engine performance.

If it's horse power and not torque you want, increase the engine's RPMs and get a bit more horse power.

Re: Electronic Ignition

Mon Oct 08, 2012 10:03 pm

WLM Cub wrote:Just remember to re-gapp the plugs to .035 for best performance. You should not expect quite that much power gain, 3 to 5 would be more realistic. But they run and start better. Bill. wlm cub


Really :? , didn't read that in the instructions (or missed it), but makes perfect sense. I'll have to regap the plugs on both my E/I Cubs. Thanks for the heads up :-:-):

Re: Electronic Ignition

Tue Oct 09, 2012 3:34 am

I have them in all 3 of my cubs and love it. No worry about points burning or slipping out of adjustment a bit at a time until one day I have no power or it won't start at all. Starts faster, runs smooth and with my rebuilt engines using late model parts I could tell the difference in power.
I'd highly recommend them to everyone. :{_}:

Do a little more digging for better prices, the last set I got for around $80 at www.carshopinc.com

Re: Electronic Ignition

Tue Oct 09, 2012 6:54 am

Yes, shop around for a good deal, I see the price on these all over the place. I've bought several from Carshop, that's a pretty good source. On the dyno, we saw 10% improvement in both horsepower & torque, on a 184, your results may vary. I've installed several of these on Cubs and all are working very well. In the Pertronix instructions, they say you "can" increase the plug gap to .035". We didn't do that for the dyno test, we should have re-gapped the plugs & made a third pull. I don't know how much difference that will make but I suspect it will not be much. At any rate, when new plugs are installed or you remove the plugs for any reason, you might as well open the gap up.

Re: Electronic Ignition

Tue Oct 09, 2012 7:20 am

I suspect that IH specified .0.025 as the plug gap because of the magnetos. The 0.025 gap is easier for the low voltage spark at cranking for the magneto and stresses the magneto coil insulation less at all speeds. A magneto produces greater spark voltage as speed increases. Battery ignition produces greatest spark voltage at slow speeds. IH used lots of Delco electrics on the tractors. Chevrolets of the Cub era also used Delco and a spark plug gap of 0.035. My 12 volt conversions and the one electronic ignition conversion are run with 0.035 plug gaps.
For battery ignitions using components similar to the Cubs, wider gaps give better performance at a low speeds and smaller gaps perform better at high speed. But high speed is well beyond 4000 RPM. Cubs at full speed are really not much more than fast idle.
I cannot discern any performance difference on the 140 with electronic conversion and a well-done points tuneup. But points do deteriorate with wear and corrosion and require attention eventually.

Re: Electronic Ignition

Tue Oct 09, 2012 7:57 am

Ignition timing retards as the point gap decreases. Electronic ignition eliminates both sources of power loss while providing consistant spark voltage regardless of engine rpm.

Re: Electronic Ignition

Tue Oct 09, 2012 8:26 am

Of course we could do what Gary Dotson did; install a diesel and eliminate this problem all together. :lol: :lol: :lol:

Re: Electronic Ignition

Tue Oct 09, 2012 8:57 am

They are available in 6v and 12v. My 6v '53 cub has the Pertronix and it runs great. I have a '69 cub that I switched over to 12v alternator charging system with the 12v pertronix and some how crossed a wire while changing out a battery. Some how it fried the pertronix. That was an $80 oops. I'd say you have to use a little more caution with them when changing out electrical components. Otherwise, it's a great conversion.

Re: Electronic Ignition

Tue Oct 09, 2012 9:28 am

Harold R wrote: That was an $80 oops. I'd say you have to use a little more caution with them when changing out electrical components.

True (in varying degrees) of nearly all components with solid state parts. The same oops could have easily included a one-wire alternator.
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