Electronic ignition vs. Old style points and coil

[canadianhorsepower]

BTW! Hey CHP! Are you going to build one of these circuits for the Rupnow engine or are you going with the CDI from S/S?

Steve, I'll build the circuit. It's already on the bread board only
have to do the PCB board for it.
It works very well,

 

[gus]

Hi Jeff,Steve & Luc.

At 70 Gus is entering Jurassic Era. After misleading myself on the performance of the antique H.T. Ignition Coil and Contact Points,I went ahead fearfully to try out space age CDI. Gathered enough courage to read and understand CDI.
By the time I come home from Thailand,the CDI would have arrive by Speed Post.

Thanks for the kind advice. Will report Webbie's performance with CDI transplant.

 

[canadianhorsepower]

Hi Jeff,Steve & Luc.

At 70 Gus is entering Jurassic Era. After misleading myself on the performance of the antique H.T. Ignition Coil and Contact Points,I went ahead fearfully to try out space age CDI. Gathered enough courage to read and understand CDI.
By the time I come home from Thailand,the CDI would have arrive by Speed Post.

Thanks for the kind advice. Will report Webbie's performance with CDI transplant.

Hey Gus, I really enjoy your post and spirit. All you have to be carefull with is the polarity , the rest works all by itself
good luck

 

[Art K]

Hi Brian,
On my engine I am using S/S CDI ignition and mid 70'S Datsun Points. The points are the trigger like the sensor and magnet. If I have the carb set right it runs at 6500-7000 RPM. When I had trouble with it I talked with Roy and he helped me sort out my problems, that being the engine grounds. it now works like a charm.
Art

 

[Philipintexas]

I've built a number of IC Hit-n-miss engines and the most successful ignition I've come across is to use a 12V motorcycle coil (small size) and an automotive relay that rapidly cycles the coil on/off as long as it is energized. For a slow running engine it gives multiple 1/2" HOT sparks as long as there is a closed circuit. It gives the same effect as an old buzz coil and will rock your world if you connect with it.

 

[Brian Rupnow]

I've built a number of IC Hit-n-miss engines and the most successful ignition I've come across is to use a 12V motorcycle coil (small size) and an automotive relay that rapidly cycles the coil on/off as long as it is energized. For a slow running engine it gives multiple 1/2" HOT sparks as long as there is a closed circuit. It gives the same effect as an old buzz coil and will rock your world if you connect with it.

Philip--That sounds like a very good solution. Do you use a conventional set of points to open and close the circuit to the relay? If so, you must have to engineer some "dwell" into the ignition cam.---Brian

 

[gus]

Hey Gus, I really enjoy your post and spirit. All you have to be carefull with is the polarity , the rest works all by itself
good luck

Hi Luc,

Thanks for the great advice. Electronic items are polarity sensitive. Get wrong
and my US$$$$$ goes poooooffff.


Now in Samui Island off the mainland of Thailand. The Weekender Resort has its own backyard beach with topless sunbathing but I have not been there yet. The island is quite remote from the mainland and the local police is blind-eyed.

 

[Philipintexas]

Philip--That sounds like a very good solution. Do you use a conventional set of points to open and close the circuit to the relay? If so, you must have to engineer some "dwell" into the ignition cam.---Brian

Actually the opposite is true. I had problems with one single-cylinder engine, the "Points" were a metal plug sticking out of an insulated disk making contact to ground every other revolution of the flywheel. They revolved so slow the coil would not spark. A quick connect/disconnect would produce a spark but normal speed would not. With this method you get hot multiple sparks as long as there is contact. Translates into hundreds of chances for ignition. At 12V and multiple sparks I don't think the relay will live too many years, but at around $5 it's easy to replace.

If you Google "BOZZCOIL" you can get everything you need. It's not my idea, but I'm sure a believer.

 

[canadianhorsepower]

you can use an electronic relay to do this job same specs guaranteed
1000000000 pulse

 

[Brian Rupnow]

Okay--The verdict is in. I like the electronic ignition. The spark is constant and dependable, and it seems that as long as one follows the manufacturers instructions they are not as fragile as I had feared. The $105 was a bit hard to swallow, but that price included the battery pack and charger. If I build another engine, it will be cheaper ($85.00) because I won't have to buy the battery pack and charger again. I'm absolutely sure that if I were to purchase components and wire up my own electronic ignition from components it would be cheaper still, but I really don't want to do that.---Brian

 

[gus]

Okay--The verdict is in. I like the electronic ignition. The spark is constant and dependable, and it seems that as long as one follows the manufacturers instructions they are not as fragile as I had feared. The $105 was a bit hard to swallow, but that price included the battery pack and charger. If I build another engine, it will be cheaper ($85.00) because I won't have to buy the battery pack and charger again. I'm absolutely sure that if I were to purchase components and wire up my own electronic ignition from components it would be cheaper still, but I really don't want to do that.---Brian

Hi Brian,
Gus now tempted to switch over to CDI for Webbie. You are right, spark from Jurassic HT Ignition Coil not as good as from CDI.
Will definitely go CDI for "Ruppy".
Will also make same Hall Effect pickup adapter to advance/retard firing.
Tidal time & height no good this weekend.May stay back n play engine driver.

 

[Brian Rupnow]

Luc--Now that I have a price ($85) from S & S engineering for a complete cdi ignition including a hall effect switch, magnet, and a silicone sparkplug boot but not including the batteries or charger, what do you think a comparable price would be to build basically the same thing from components?----Brian

 

[canadianhorsepower]

a complete cdi ignition including a hall effect switch, magnet, ----Brian

Brian-- your probably looking at 10.00 at the most
and 1hr max of work. Here is the link and you could use a standard
car coil or a motor cycle coil

http://www.homemodelenginemachinist.com/f31/new-ignition-circuit-20415/index10.html#post229024

 

[stevehuckss396]

Brian-- your probably looking at 10.00 at the most
and 1hr max of work. Here is the link and you could use a standard
car coil or a motor cycle coil

http://www.homemodelenginemachinist.com/f31/new-ignition-circuit-20415/index10.html#post229024

How much is a standard coil? You also need to buy high volt wire, vacuum fittings for the spark plug boot and the spark plug. You kind of need to compare apples to apples.

 

[Brian Rupnow]

In my end of the world, a 12 volt coil costs +/- $50 by the time you factor in tax at 13%. A high tension wire and silicone sparkplug boot runs about $10. So now we are up to $60 plus Luc's $10---Call it $70. Plus I still have to wire the components into a circuit. That starts to make the $85 I would pay Roy Sholl look reasonable.--(Roys price does not include the sparkplug either.)

 

[canadianhorsepower]

How much is a standard coil? You also need to buy high volt wire, vacuum fittings for the spark plug boot and the spark plug. You kind of need to compare apples to apples.

I agree with you Steve,I should have been more precise,
the coil, HT wire and spark plug boots can all be picked up
USED in a small engine shop for ten dollars.

The reason I didn't mention them In the quote price
is that I know Brian have some coil lying around in his shop
that he could use:hDe:

 

[stevehuckss396]

In my end of the world, a 12 volt coil costs +/- $50 by the time you factor in tax at 13%. A high tension wire and silicone sparkplug boot runs about $10. So now we are up to $60 plus Luc's $10---Call it $70. Plus I still have to wire the components into a circuit. That starts to make the $85 I would pay Roy Sholl look reasonable.--(Roys price does not include the sparkplug either.)

And also your time to assemble everything. You also need futaba connectors if you want things to be quick disconnect like Roys. They are 6 bucks and you need 2 of them. Then there is the physical size of the components. It's alot easier hiding the CDI board than a car coil.

I made my own plugs for the V8 not to save money but because I couldn't buy them anywhere. It's not that hard but takes alot of time. I also know what it takes to make a mold and make spark plug boots and that takes a lot of work. Both of these things I do now because I have the tools and fixtures now and it does save a lot of money. I dont think I could build a cdi board that small with that hot a spark for 35 bucks or 50 with a coil. I think that the CDI board in the long run is cheaper and the other thing is, they just work great.

Weather you buy one from roy or another source they are really a good way to go. I personally buy from roy because he is the one I see at the shows personally supporting the model engine building hobby. Plus if I can wait for a show to purchase what i need I can save on shipping. Not only that but he is one hell of a nice guy. Anybody who has ever talked with him knows that.

My .02

 

[canadianhorsepower]

The best thing for you Brian is
this kit from Roy, don't get me wrong I have nothing against them
I was getting stuff from his father 30 years ago

a hall sensor is 1.20

 

[canadianhorsepower]

And also your time to assemble everything. You also need futaba connectors if you want things to be quick disconnect like Roys. They are 6 bucks and you need 2 of them. Then there is the physical size of the components. It's alot easier hiding the CDI board than a car coil.

I made my own plugs for the V8 not to save money but because I couldn't buy them anywhere. It's not that hard but takes alot of time. I also know what it takes to make a mold and make spark plug boots and that takes a lot of work. Both of these things I do now because I have the tools and fixtures now and it does save a lot of money. I dont think I could build a cdi board that small with that hot a spark for 35 bucks or 50 with a coil. I think that the CDI board in the long run is cheaper and the other thing is, they just work great.

Weather you buy one from roy or another source they are really a good way to go. I personally buy from roy because he is the one I see at the shows personally supporting the model engine building hobby. Plus if I can wait for a show to purchase what i need I can save on shipping. Not only that but he is one hell of a nice guy. Anybody who has ever talked with him knows that.

My .02

Steve I don't think you need to jump on my head like a jack hammer:hDe: cause I answered a question, read my other answer
cheers

 

[stevehuckss396]

Steve I don't think you need to jump on my head like a jack hammer:hDe: cause I answered a question, read my other answer
cheers

I'm not jumping on you. Don't think i'm trying to poo poo your ignition system. I was just trying to show the reality of building one yourself. Many guys including myself don't have a garage full of used parts so I have to purchase what I need. I agree that if you have access to used parts a lot of money can be saved. All i'm saying is if you need to source everything, the CDI is a good way to go. That's all.