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Discussion Starter #1
I have a 79 2L S2 SPICA.
I am going to convert from points to an electronic distributor. I have searched the forum and see a mixed result on recommendations.

Is there a clear favorite today?
I want something reliable for everyday use.

Any insights on current experience would be appreciated along with recommendations!

TIA
Gary
 

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There has been lots of discussion on this - a search will give you lots of information. There are positive and negative experiences with all of them. I like the 123 because it has a selection of advance curves and you are guaranteed to find one that suits your engine.
 

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I am a great believer in replacing points with optical or hall-effect sensors, so I agree with your decision. But, what do you hope to achieve by the change? Easier starting, better top end, more aggressive advance curve, replace a worn distributor ....? Different products will produce different results, and carry different prices.

I have had good luck with simply adding a Pertronix electronic trigger to my Bosch distributors. This does nothing to change the advance curve (need a 123 for that), and isn't the most high-performance solution (MSD might be the answer there), but it is inexpensive (around $75), easy to install, and doesn't require sticking a huge box on my firewall.

You probably have a Marelli distributor - I'm not sure if there is a Pertronix part that fits the Marelli.
 

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Discussion Starter #4
Distributor Replacement

Alfajay,

I am just trying to get my 79 up and running. I have very limited time to work on it on weekends. I have gone through the Marelli, completely disassembled, cleaned and reassembled including new points, condenser, rotor, cap, wires, coil and plugs. I got it going but could not get a very good spark. This was after I reworked the entire fuel system, new pumps, filters, hoses, etc.
Anyway, I am looking for a drop in distributor that I know will work. The idea of multiple advance curves and no points is a plus. I looked to see if there was a pertronix that I could install but gave up as I do not have the time.

New distributor is in hand and I will install this weekend.
Stay tuned............

I need to get a Spider on the road so I can get some wheel time. Then I can experiment with modifying the existing distributor. At least I will have a good spare.

Thanks for the feedback and comments.
 

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But Mad North-Northwest
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But Mad North-Northwest
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I have no experience with SPICA FI (except for removing it and selling it) and all my older 2L and 1750 cars had carburettors. On those cars, a strong spark made a big difference. Webers are notorious for having a lean spot at the top of the idle jet range which can cause a hesitation or flat spot. A strong spark will often make the flat spot disappear. Points will work fine if everything is perfect, but it does not take much to get a weak spark.
 

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Wow, no idea how good it is, but it looks like it's only $185 for the whole thing. That's pretty darned reasonable.
PERTRONIX D185604 Alfa Romeo Cast Distributor $185.95 BUY ONLINE
Wow, that is reasonable. From the photo, it sure looks like the same distributor that Pertronix is selling for $298. See: PerTronix - Search

It would be helpful if they published the advance curve - some of these aftermarket Bosch distributors are engineered for air-cooled VWs, which max out at about 4,000 rpm.
 

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Jay, I think I read someplace that the Pertronix distributor for Alfas has an adjustable advance but it only has a max of 20 degrees in the distributor. Probably you could rework the distributor to get some additional advance if you needed it. I don't know if it comes with it or not but the Ignitor II is much more robust than an Ignitor I.
 

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Trained (ex)Professional, , 1953-2018 RIP
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...it only has a max of 20 degrees in the distributor.
Please keep in mind that since the dizzy turns at half crankshaft speed, 20 degrees distributor advance equals 40 degrees at the crank.
 

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Sorry for the trip out into the cornfield, but:
Webers are notorious for having a lean spot at the top of the idle jet range which can cause a hesitation or flat spot. A strong spark will often make the flat spot disappear.
How does a stronger spark make up for an actual lack of fuel?
 

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A stronger spark will ignite a leaner mixture.
 

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True enough. Leaner mixtures require a higher voltage.

However, if a stock ignition system can not fire a lean mixture, that is one seriously lean mixture. In my opinion, it is better to address the root cause of the problem, the lean mixture, rather than the symptom by upping the available voltage.
 

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Please keep in mind that since the dizzy turns at half crankshaft speed, 20 degrees distributor advance equals 40 degrees at the crank.
Thanks, Jim. I always get that backwards. Pertronix doesn't publish much technical information on their wares and the distributor is simply described as being "for" an Alfa Romeo 1.3-2.0 liter engine. I don't recall where I saw the reference, but if the distributor really does have up to 20 degrees advance and only costs $185 w/ ignitor it is definitely worth looking into.
 

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However, if a stock ignition system can not fire a lean mixture, that is one seriously lean mixture. In my opinion, it is better to address the root cause of the problem, the lean mixture, rather than the symptom by upping the available voltage.
Hi Jim,
An ignition system that delivers a high energy spark is more forgiving of marginal caburation. Weber mixture strength is always a compromise. Some folks are happy to run rich in places to avoid being lean in others. I prefer to run a little lean in some places to avoid running rich in others. A Marelliplex or an MSD box that can drive high energy coils have definitely worked better for me.

Running an ignition system on the bench tells you a lot about it's capability. If the spark is loud and bright white then the temperature in the spark is high and it will ignite a wide range of mixtures. If the spark looks and sounds weak then the temperature in the spark is lower. The temperature is determined by the current and the duration of the spark. A coil that has more stored energy can transfer more energy into the spark. If a distributor cannot drive a low impedance coil then it may be a limiting factor in producing strong sparks.
 

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In his new book, David Vizard talks about the advantages of plasma ignitions. I found this interesting example on YouTube. Apparently this will work with a lot of distributors.

 

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Never tried it, Jim, but the FAQ page on that aquapulser site sets off my snake oil detector. 8-60% mileage increase, indeed: caveat emptor.

Anyway, given how well modern coils, spark plugs, and basic electronic ignitions work, I just can't see the need for something like this on a street car.
 

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I mean no disrespect to anyone but the marketers are banking on the fact that the potential buyers of 'high performance' ignition products known virtually nothing about how or why an ignition system actually works. So the marketers are hitting grand slam after grand slam all the way to the bank.

Bright lights, loud noises, polished Finnegan pins nor ritual sacrifice can change the fact that a coil will output only the voltage required to fire the sparkplug. Period. If a plug requires 10kV to fire, a 10 billion volt coil will output only 10kV to fire the plug.
 

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I agree about the Aquapulser hype. We've seen this kind of marketing before for so many years. Still, the concept is intriguing because, as Vizard talks about, the plasma pluse is so strong that it can help to overcome some of the inherent combustion/flame front limitations of a hemi head with domed pistons. I don't mean to hijack the thread, but we use breakerless/inductive/capacitive discharge electronic ignitions to provide us with more stable and enhanced ignition events. Hype aside, if this is a viable technological innovation it would be interesting to investigate.
 

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Bright lights, loud noises, polished Finnegan pins nor ritual sacrifice can change the fact that a coil will output only the voltage required to fire the sparkplug. Period. If a plug requires 10kV to fire, a 10 billion volt coil will output only 10kV to fire the plug.
[/QUOTE]

You left out purification rites and funeral pyres, Jim. :) You are entirely right about this. But electronic distributors, aside from eliminating points and providing a smoother operation, also have the advantage of delivering a higher energy spark. Granted, under proper running conditions, that ability isn't necessary. While a regular inductive ignition won't give much (despite the hype), something on the order of an MSD when teamed with my favorite Marelli Plex has some advantages. A points/coil ignition for instance won't easily fire fouled plugs while an MSD6A definitely will. Further, when I added the MSD to my old Alfetta's Marelli Plex it easily eliminated a preignition problem resulting from 10.4 compression and 91 octane gas. That's not an optimum condition but it's also not an uncommon one, either.

OK, full disclosure. My Super runs quite happily with it's points/coil ign. and garden variety, Champion N-4C's.
 
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