Distributor options
- Thread starter chumley
- Start date
Ics19
belle macchine!
Out of interest, what coil did you get? Typically, the ones to match the modules need to have a very low primary to get the best results. But consequentially they do get hot and as mentioned in a previous post, the heatsink'ing of the module is important - the chunky plex type in the drawing is a great design that also holds the coil, but you can get some finned aftermarket ones for just mounting the module that may be suitable.
dllubin
Don
You should find out what the ignition box is expecting for a coil primary winding impedance before you select a coil. If it is too low, the box will overheat and not last very long. For example, the stock X1/9 Bosch box uses a coil with a primary resistance of 1.1 to 1.7 ohms plus a ballast resistor in series that is 0.85 to 0.95 ohms (total resistance = 1.95 to 2.65 ohms). Some coils have an internal ballast to eliminate the need for an external ballast (the 1300s were like this). The advantage of the external ballast is that the coil does not have to dissapate as much power and runs cooler.
dllubin
Don
The pictures are nice to look at but data sheets would be more useful to check compatibility. I would check to see what the ignition module expects to see for a coil primary. Also make sure that the module is mounted to a good sized heat sink with thermal paste and put it some place where it will get air flow.
As far as the distributor goes, does it have a centriful advance curve close to what you are looking for? I don't know what year your car is and what the UK cars had for emissions control. In the US, the pre FI cars had some pretty weird advance configurations to pass emissions. You might want to look for an advance curve similar to the Bosch FI distributor from a performance point of view.
kmead
Old enough to know better
The coil from a 124, a Bosch Black or Red coil I think, would work with the GM chip. It will definitely need a heat sink. Finding a 124 heat sink with coil would be ideal for this.
Ignition Coil, Bosch L-Jet 4 cyl - (SKU 21-2321) | Vick Autosports
Ignition Coil for electronic ignition Fits: Fiat X1/9 1979-88 Fiat Spider 1979-85 Alfa Romeo Spider 1982-89 (replacement for 21-2804) *NOTE: This works with distributor SKU 21-6325 & SKU 21-6331*
www.vickauto.com
This one can also be used:
Performance Flame Thrower II Ignition Coil - 1979-85
Magneti Marelli Pertronix electronic ignition coil FIAT Spider 2000 and Pininfarina - 1979-1985 - Auto Ricambi, IG2-466, 45011, 9938064, BAE207A-MK1, 60700305
autoricambi.us
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Ics19
belle macchine!
I recall there was some discussion on this previously with the GM module conversion, and @Yves ended up with the 105 coil and no ballast, but a decent heatsink - this is not unlike a stock 124 or Montecarlo S2 system.
Bosch ICM modification with GM HEI
I try the "Rebuild your Bosch ICM for about 10 bucks" from Bob and I have an issue. My X, 1500 FI with Midwest Bayless performance head. The engine run smoothly and don't have any issue, I just want the new GM HEI module for electical power saving and improved the spark. The issue is a fast...
xwebforums.com
dllubin
Don
It looks big enough. Does it have an absolutely flat surface that you can attach the ignition module to? It needs to be pretty flat for the thermal paste to be effective. If yes, you may have found a heat sink.
Ics19
belle macchine!
The factory ignition module for Bosch systems used discreet components in a box that had the connections via the green cable block. The box can be rebuilt/replaced by using a more modern module, like you have, and can still appear original. If you're confident in not getting the module wet and want additional heat dissipation, then there's no need to keep the box. The initial thread on this great mod is here:
Rebuild your Bosch ICM...
Rebuild your Bosch ICM for about 10 bucks. Here’s a new twist on a subject that’s been broached a few different ways in past discussions of replacing the Bosch Ignition Control Module. I say “about 10 bucks” but the total might be as high as $15 if you have to go out and buy the misc. items...
xwebforums.com
You can get an idea of the original box & cables on the MWB site:
Electronic Ignition System Bosch (Fiat Bertone X1/9 1981-88, + All X1/9, 128) - U8
Electronic Ignition System Bosch (Fiat Bertone X1/9 1981-88, + All X1/9, 128) - U8
www.midwest-bayless.com
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Ics19
belle macchine!
The factory wiring in your case for the negative coil terminal was just a Brown/White cable to rev counter and a Green cable to distributor points - is this what you have? The green cable should no longer be connected at the distributor so I would disconnect the coil end too to avoid any possible shorting, but maybe cable tie it to one side in case you want to re-instate the factory setup in the future.
Yes that's what I have pink live to pos and brown and green which were spliced together from original set up i didn't realise has when I got the car somebody had put a electronic module inside dizzy and must have cut wire by dizzy but would that go through the loom or straight from dizzy ..I'll remove green wire and see what happens many thanks for your help once again.
Ics19
belle macchine!
The green wire at the distributor (previously for the points/condenser) is simply run into the loom and comes out again at the coil - it doesn't sound like that's your problem though, but good to tidy up.
Having a nightmare at minute starts fine on the button but won't rev when timed to mark when I advance a massive amount lot better but then obviously won't start has way to much advance I do now have a vac advance on this dizzy do I need it or any other ideas welcome. I have twin IDF's so where would I put one thanks
dllubin
Don
What does the centrifugal advance curve look like for that distributor?