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Vanilla 1.1.5a is a product of Lussumo. More Information: Documentation, Community Support.

    • CommentAuthorjay rich
    • CommentTimeMar 2nd 2010
    just asking who still sell them and with the 2 wire set up i found some on jerry howell site but with a one wire set up
    ....jay and as for my j 8 i am still bulding valves pain in the but
    Alot of people seem to be switching over to the S/S setup. His coil is about the diameter of a nickle and less than an inch long. Very compact.


    Very bottom of page.

    If you are looking for the coil only and not the full igntion system CDI, one option is to buy a motorcycle coil, I bought one Nology brand, two sparking terminals 45,000 volts, work great with contact points and condenser but they run about 45.00 USD, check with your local motorcycle shop.
    But S/S setup for 90.00 USD looks more attractive, since it is ready to go, has cables, connectors etc.

    How are you making your valves ? one piece or two pieces silver soldered ?

    best regards.
    • CommentAuthorjay rich
    • CommentTimeMar 5th 2010
    pain in the but 2 peice and i have to look into the coil just a thing i want to think of for the next engine i would like to try after i get the j 8 purring oh yes i forgot i would like to find some small miter gers for the distributor for the j 8 two 45 gears to stand the distributor up inside bore of 0.18750 thanks guys for the info ....jay
    • CommentAuthorgbritnell
    • CommentTimeMar 6th 2010
    I don't know anywhere that you could get gears that small. The smallest SDP stocks is .312 O.D. and they are 48 pitch. Anything smaller than that I'm afraid you'd have to make them yourself.
    • CommentAuthorjay rich
    • CommentTimeMar 8th 2010
    i was affraid of that thanks for the info george
    Have you tried Stock drive products (SDP/SI) they have some bevel gears in brass and steel, they are not cheap but beats trying to make them yourself, I make most of my spur gears but buy internal / bevel / helical from them or HPC in the UK, HPC has a more limited selection and are priced in UK punds ( almost double than SDP/SI).
    Some gears I used in the past for the distributor drive were from them, inside bore 0.125, outside diameter 0.375, 18 teeth, Brass 20 deg Pressure angle 48 DP.
    This was the part number, they run about 11.00 USD each, you have to buy two of the same if you want to keep the ratio 1:1.
    • CommentAuthorjay rich
    • CommentTimeMar 10th 2010
    i have got to try them thanks for the info jamie
    • CommentAuthorRray
    • CommentTimeMar 18th 2010
    I'm very new to this site. Can someone tells me the diff between CDI and the traditional ignition coil with point and capacitor? what is the advantages and disadvantages of each?

    Thank you
    Check an excellent write up by David Kerzel in the tips & links section, worth a read.

    In summary one CDI uses magnets and a Hall effect transistor ( sensor) to trigger the spark, they tend to be more powerful than model coils in terms of voltage, they are more reliable and last longer than model coils.
    Traditional contact points and capacitor with a model coil are the mostly used and they do good, however they seem to need more maintenance and cost less.

    CDI producers, they are a couple CH who incorporates a time advance mechanism ( electronic ) and there is another company in Ohio S/S machinery who sells units with no time advance but cheaper.

    I used to build using contacts and coils and now have moved to CDI from CH and I love them, makes life a bit easier once you learn the gremlins ( arcing can damage the hall effect sensor very easy).
    Best regards.
    • CommentAuthorkamran
    • CommentTimeMar 18th 2010 edited
    Additional to what Jaime said
    With CDI you don't have to worry about the dwell time since we're talking microseconds vs milliseconds with contacts
    CDI will give you much better performace for high RPM engines, but the spark is shorter in CDI.
    Some CDI comes with microcontroller that automatically advance and/or retard the spark based on the RPM
    CDI has advantage over contacts if the spark plug is fouled.
    • CommentAuthorRray
    • CommentTimeMar 19th 2010 edited
    very confused.
    why RPM has anything to do with it?
    Also why you don't have to worry about the dwell angle?
    Try to keep this as simple as possible with out getting too geecky is hard.
    Contact point ignition better know as Kettering system depends in the dwell time ( time the contact points remain closed) to recharge / load the coil that will produce the spark when the contact points open and force the magnetic field to collapse.
    What does this mean, the longer the dwell time the more energy stored in the coil to produce a spark, too little dwell not enough spark, too much dwell causes overheated coil and maybe burn coil if ignition left "on" while engine is off and contact points are closed.
    CDI ignitions use a trigger mechanism based in a magnet, the coil charge time is not dependent on the time the magnet sensing "hall " effect switch remains open or closed but is controlled by a capacitor, so you do not have a dwell time but a discharge time, which tends to be smaller (time) than in the Kettering system.

    SO what does the CDI produce, like Kamran mentioned, higher RPM's. since the CDI system recharges faster than Kettering, it allows to have a good spark at higher RPM's, this becomes more noticeable in multiple cylinder engines where the coil needs to generate a spark more than once per crankshaft revolution.
    Since coil delivery voltage is not dependent on dwell time, the voltage delivered by the CDI does not decrease with RPM's, allowing to run cleaner plugs and have a decent spark in engines with higher compression ratios. In one case I had problems getting a spark in my engine which develops 65 PSI of compression with Kettering system and had no problem running same engine with CDI.

    Sorry for the long answer, cheers.
    • CommentAuthordavid
    • CommentTimeMar 19th 2010
    Nice discussion. Coil energy and spark energy drop as RPM go up.
    CDI tends to have higher energy levels and like Jamie explained every spark is full power fast or slow.
    Ray, do you have a specific question about ignition or is it just general?
    • CommentAuthorRray
    • CommentTimeMar 22nd 2010
    Thanks all for the info.
    No I just needed some general info. trying to see if I can build my first engine.....