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Discussion Starter #1
Since there might be some inte

Since there might be some interest on the board, here is my research on ignition replacement options for 308s and 328s. Will cover distributor based systems first

Anatomy.
First it's important to know a few differences between the cars.
Early Euro 308s - Single distributor with twin points driving twin coils. Basically twwo distributors sharing a common cap. Late in the run there is a version of this single distributor with an electronic pickup (rare, sought after, and expensive).
American 308s - two 4-cyl distributors run by two sets of points in each distributor. One is specifically set to modify the timing for emissions purposes at slow running. Many folks simply disconnect these as they are not neccesary to run the car and can be a poop to set.
Fuel injected cars - here we go to Marelli electronic ignition driven by magnetic flywheel sensors. The 2v and qvs have 'Digiplex' systems with two seperate electronic control units (ECUs) firing a coil for each bank, which is partitioned out to the sparking plugs via a cap and rotor on the intake cams of each bank. The 328 and Mondial 3.2 updated to 'Microplex' with a single ECU driving both coils.

Aftermarket replacement issues:
This focuses on the little cam plug on the intake cam that will either drive a distributor as in the early V-8s, or three different rotor drives on the Digiplex/Microplex ignitions. It is important to note that the cam must come out for this plug to be changed. The 2v mounts a post drive for a now near extinct rotor (read $$$$) while the qv rotor post is different and the rotors somewhat more available (read $$). A popular option for 2v guys is to convert to the qv rotor and driver. The 3.2 liter engine is the most funky with the rotor held on by 3 screws into the plug on the end of the cam (TRs are similar). The caps on all of the electronic ignitions are the same.

Options out there:
1. The single Euro distributor pretty much bolts on I'm told to the same distributor drive as the US cars. These are available, but a bit dear, especially the Euro electronic triggered version (purchase sources: Steve Ahlgrim, Dennis McCann)
2. A popular addition which increases the life of points and improves the spark on distributor engines are boxes like Multiple Spark Discharge (MSD) units. These work to lower the current across the points giving them a much longer life, and yield longer sparking duration improving idle and performance.
3.Many points have been converted to optical triggers (e.g. Pertronix), replacing the points and usuall combined with an MSD or other driver. It's important to use a ballasted resistor with the coil if not using an MSD, as ALL optical triggers (Pertronix, Mallory, etc) are sensitive to voltage spikes.
4.The Ben Millermon Single Distributor Conversion Tampa resident Ben Millermon has pioneered a custom single distributor using a standard Mallory optical trigger with readily available caps and rotors (Search www.FerrariChat.com. for details) There are many of these on 2v cars replacing the dual distributors and owners say they work quite well. These clamp on where the cap was and use the stock rotor drive post. Development problems centered around driving the tach, but he has a custom tach driver now. Cost around $500 without an MSD. While not yet commonly available for the funky 3.2 rotor mount, it is in development.
5. Norwood Performance Single Distributor. This Dallas Texas based Ferrari shop converts 2v distributor to an electronic trigger and somehow uses a Chevy cap. I think the cost is also around $500. They do not do these for 3.2s
6. Mallory Unilite distributor and Norwood adaptor. What Norwood will do for 3.2s is make an adapterkit for the Mallory Unilite electronic distributor for a flathead V-8 Ford. This plate bolts on to the head and attaches an offset drive dog to run the $238 Mallory distributor. The kit costs about $550 - $600

Distributorless Ignitions
If you want to keep your fuel induction but go to a distributorless electronic ignition, Electromotive make a unit for the Ferrari available from Nick's Forza Ferrari. It uses a magnetic sensor mounted on the front of the engine reading pulses from a ring that is machined onto the front pully or damper. Cost is about $1500 before installation. Nick sells the unit already modded for the Ferrari tach drive.

Tachometer drive
While we are on the subject, the Ferrari tachometer in the V-8 cars mentioned is really a 4 cylinder tach that is run off of one cylinder bank's coil or ECU. This is important if you are going to a single coil set-up. If you are unable to use the original sensors and ECU to drive the tach (will let you know in a couple of weeks) then you need to get a converter from Ben Millermon or have a reputable tachometer place convert the tach to a single coil signal.

Please let me know of any corrections or additions. Hope this helps.
best
rt

Pictures:
Euro single distributor schematic


Millermon Distributor installed


Norwood single distributor


Mallory Single Distributor
 
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Discussion Starter #2
RT, thanks for such a comprehe

RT, thanks for such a comprehensive overview!

By far the cleanest looking of the bunch is the Mallory pictured imo.

For owners of carbed cars, don't forget that when converting the Marrelli Distribs on the early carbed cars that they still have flywieght issues to contend with, that when frozen, loose or worn out cause a multitude of poor running ills.

Regards, JRV
 
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Discussion Starter #3
Here is update #1 to the origi

Here is update #1 to the original tome:

A Crane unit falls into the optical trigger category much as the Pertronix.

Here's the link to the new and improved Norwood website on the single distributor:
http://www.norwoodperformance.com/engine_electronics.htm
This includes an MSD, harness, block off plate and tach conversion - pretty much a straightforword parts swap for carb'd 308s with a couple of wires. Total price is $1495 + shipping. Installation would be 2 - 3 hours I'm guessing.

Ben's unit is much less expensive at $500. Same installation time, maybe a bit less. Not as clean as the Norwood installation, but simpler. Ben does not include a block off plate for the unused side. Adding an MSD 6AL box with an 8000 rpm limiter ($200) puts the whole she-bang at about $800 with incidentals I'm guessing.

A note for FI guys moving over to the Mallory or any distributor set up or Electromotive: you now have the advantage of setting your timing not available with the Marelli ECU.

Nick used to have more info on his website on the electromotive which I copied to my other computer - will try to get that if I can find it. The people that have it really like it, and it does give you the ultimate in control of the spark. Not sure how robust it is, there are some threads in the archives of those that have used it. It has 2 or three dial set pre determined break points and can have a MAP sensor for extra $$. The only mechanical concern I have is the mounting of the sensor and trigger wheel in the front as it looks pretty home made and can look pretty ricy if not done well (I may take some arrows for that, but why did they make it electric purple for Pete's sake?). Not sure of the costs over and above the $1500 purchase, would guess a few hundred bucks to install the trigger wheel. So I'm guessing total soup-to-nuts on this if someone else installs is about $2K.

Something I forgot to mention is you can drive the ignition with a programmable Motec ECU with input from multiple sensors and coil per plug setup, but I think the juice for the squeeze is getting pretty low for just ignition replacement ($$$$$$). This is one of those that is great if your'e getting some entertainment value from it. Personal opinion only here.

As far as what's right for you, well it depends on what you want to do. If you're going racing, would opt for the Electromotive. If you are a street guy and want to increase reliability with a stock look would go with Norwood (or Mallory with a 3.2). If you are going for reliability, cost-effective simplicity and non-stock appearance is ok, the Millermon is the way to go.

This is just all my ranting here, and I'm happy we as Ferrari guys actually have some options. hope all of this research is springboard into making an educated decision. JRV may have some more educated input, but I'm also sure he would tell you that no matter how good the part, correct installation and set-up plays a big part

Feel free to post or email me directly with any questions or comments! I'm here to help.
best to all
rt
 
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Discussion Starter #4
RT, I have a 308 in the shop

RT, I have a 308 in the shop at the moment with an older Norwood single distrib. The cap on this one fits quite loosely and the clips are just bent metal held on by luck.

Do you know if they have better caps and cap hold down clips these days?

Regards, JRV
 
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Discussion Starter #5
JRV

This is not the first t


JRV

This is not the first time I have heard this about the Norwood conversion. I did not mention it as I do not have a good handle on the problem. One of the customers I talked to mentioned that the cap can slide around. Not sure what is current. Just looking at the picture, I might use the existing cap mount bolt holes to place pins (cut off bolts) that would fit in notches in the cap to hold position.
Certainly worth a call.
Of course, you could always put a 3.2 cam button in and mount the Mallory with no wiring changes.


OBTW - sent them a Mallory distributor this week - more on this as develops. If you want them to do two kits, now's the time.

best to all
rt
 
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Discussion Starter #6
Got the Mallory distributor ad

Got the Mallory distributor adaptor development pictures back from Norwood. Am a little concerned about clearing the oil cleaner.
Their driver replaces the 3.2 rotor mount, which he says can be done with the cam covers still on. JRV?



 
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Discussion Starter #7
Hi RT,

Looks like it will w


Hi RT,

Looks like it will work, larger than I thought it would be. yes I think you may be able to pull the old drive off & exchange for the new with the cam cover on. It will take some care removing the retaining pin, but it should work out.

Am I correct in assuming this Mallory distrib will run off the 5-8 intake cam? Has anyone verified room & clearances in the engine compt. of this new set-up?

Regards, JRV
 
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Discussion Starter #8
Yes - it is a little taller th

Yes - it is a little taller than I imagined. James said he would fix it if it did not fit.
I do want to put the distributor on the front bank.
I test fit it before I sent it off and there was lots of room left over with a smaller adapter. It may be close - will knowin a few days.
 
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Discussion Starter #9
OK, I'm about to dive into

OK, I'm about to dive into this. It's tough to do as I am really enjoying driving with the new carbs - it seems even smoother and revvier than with the injection - and what response!

Since ease of maintenence for dummies (read: me) was an initial criteria, Will be placing the distributor on the AFT bank also ensuring clearance.

Am still waiting on Ben's distributor with a new mounting ring.

Will begin making the wiring harness this week. I am thinking of starting with a non-MSD straight ignition set-up to eliminate variables as I work out the bugs - or should I just go abead and wire it in? I'm told the MSD reliability is excellent as lomg as it doesn't get too hot.

I am hoping to use the original marelli ECU to drive the tach (see below), but am readying alternatives.

I have a set of Taylor Spiral core wires, and will try to avoid the dreaded plug extenders, but may not be able to.

Any advice welcome.
best to all
rt

 
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Discussion Starter #10
Looks like you've got this

Looks like you've got this set-up fully analyzed. I'm very curious to know if the old ECU will act as a Tach surrogate and pass thru for the MSD. Never heard of this being tried before, but can't think of any reason it wouldn't work as long as it's powered up.

Regards, JRV
 
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