I installed a MSD 6a ignition in the winter time to save the original Magnetti Marrelli unit on my 512BB. I know some people here drive with MSD units and my question is did you also change the coil? Because a MSD coil has no separate ground connection. I hoped it would start better (easier) . But I am not satisfied with the way it runs and the car is misfiring when it runs at 3000 to 4000 RPM,s Maarten Image Unavailable, Please Login Image Unavailable, Please Login
I have been running an MSD 6a ignition with a High Vibration Blaster coil since 2002. The MSD High Vibration Blaster coil is black like the OEM Marrelli. So, I put a Marrelli sticker on it to make it look OEM. I left the OEM Dinoplex in the proper place, painted the MSD 6a unit black and placed it out of sight under the firewall so it looks like I'm using the OEM Dinoplex. The concur judge at the French Ferrari Classic in 2004 didn't even notice it.
My Boxer uses the stock coil. Running bad is odd. Perhaps the higher energy ignition is causing problems with the plug wires or the plug extenders. Also check the cap and rotor- IMO the MSD eats the cap & rotor faster but that might be just my opinion.
I have an MSD and run the stock coil. I also changed the cap, rotor and ignition wire for the exact same reason, to eliminate plug fouling and a miss at 5200 rpm. When I first installed the MSD with the blaster coil, I did notice a lot of tracking ( white stuff) inside the cap. Rocco recommended that I use the stock coil with the MSD and Voila, the white stuff is gone.
Good day Maarten, I, too, have a 512BB with MSD installed. Both the stock coil and the MSD coil work the same. I ended up leaving the MSD high vibration Coil installed feeling it was better in the long run. In regards to your missing... Ensure that the MSD unit has an excellent and thick-wire ground and power supply. Remember that the MSD draws a lot of current periodically and so wiring inductance can play a role here... the thicker the wire the lower the inductance. Secondly, I would check the connections and inspect the distributor pick-up sensor. Thirdly, inspect and clean the distributor advance weights and shaft bearings. If you are still convinced that the MSD may be the issue, reinstall your original unit (DinoPlex) and see if the missing, etc still occurs. If it still does then your problem is not the MSD. If the miss goes away, then maybe you have a faulty MSD? Cheers, Sam
Maarten - Did you inspect your distributor cap? If not, I suggest that you do so. Humidity can lead to a rain forest in there, and I found that attention to cleaning and drying led to rather significant improvement in performance and smoothness. My MSD with Magnetti coil has run perfect for 10 years. Unlikely that your difficulty is related to the MSD. More likely related to installation (large-gauge red power line) of current source, or possibly to unintended activation of the MSD rev limiter, etc. Jim S.
I am getting de distributor checked out now together with my MSD unit and coil as one system. This way we can check if the misfires are related to the distributor or not. All connections are soldered and good new wires used. I do not think the MSD unit is at fault, so it must be in the distributor(cap/rotor) or the plug wires. Befor the change to MSD the car did 12000KM with out a problem, even on many track days. Maarten
Hi Guys. I know this is a old post but I have a 512bb and it's on a MSD box and now a MSD coil, it runs great till its hot then starts play up, won't start and miss firing alot. I have new leads, dis cap and rotor. The distributor has been stripped down and cleaned. New pick sensor too. The leads has extenders on and someone said I should try resistance plugs. Is this correct or have I got too much resistance or to little? Thank you for your help.
I would meassure the resistance first. I once had such "hot" starting problem and after renewing the distributor cap all was fine again. later I cleaned the old cap and sprayed inside isolationspray, cleaning then the contacts and tried again the old cap, but still had sometimes problems when starting. once I came home at night and have been surprised: the distributor cap was like a lightning outside all over and the engine stottering. fascinating to look at. so I took then a closer look under the microscope and have seen a lot of very small cracks in the plastic that even again some isolation spray could not help. so I replaced again to the new cap remove the igition wire from the cap and put it nearly ground and a helper may start. so you see if there is a steady spark.
Great thank you for the advise. I'll order a new diz cap. What should the resistance be on the leads and spark plugs? Thanks.
would be great if you could fill out your profile a little more and introduce yourself also so we will know on what technical level you are
thank you very much. so we not have to start then from the basic original: the longer the wires the more resistance because they used not copper wires, they used resistive/carbon cables. I hate those since they are on the market. opel started with those in germany in the 70th and the french cars much earlier. so I always replaced those by copper wires with resistance sparkplug plugs with 5 k-ohm or 10 k-ohm. bosch had made those. or put a resistance between the coil and the cap
17 years for me with the MSD 7 and stock 3 prong Marelli coil. I like the 3-terminal design. It makes sense (to me) that the secondary windings return the circuit to ground. Otherwise, the secondary windings share the circuit return path with the ignition unit. MSD has this engineered in with their design, but I don't see the problem (obviously as others) with using the 3-terminal design with the MSD. Also, I concur that water can wreak havoc in the dizzy cap. Curious what others think.....
