Part 5: MSD: Multiple Spark Discharge Ignition System.
The MSD is one of a number of brands of electronic ignition. This is something that is still feared by a lot of old school tuners mainly because it's not something they understand or (more likely) not something their old guru told them about, because it is fairly new technology. So, straight to the point: Without a good ignition system to ignite the air/fuel mixture, any modifications to add engine power will be useless. Let go back quickly to the basics. To make more power you need to stuff more air and fuel into the engine, compress it and burn it. All of the bigger cams, pistons, carbs and all to get more air into the engine will be useless if you don't have adequate spark to start the burning.
Before I go on about the wonders of using an MSD, let's take a quick look at the stock system. A typical stock ignition system uses a coil to boost the electrical system's 12 volts into around 300 or 400 volts to create spark energy to ignite the air/fuel mix. One problem faced by this system is that the coil needs time to recharge and at higher RPM's there is not enough time in between sparks for the coil to reach full power so the spark effectively gets weaker as the RPM increases. The stock ignition for old-school cars will usually involve a distributor fitted with a contact point and condenser to deliver the spark. The contact point does eventually wear out requiring rather frequent service intervals if you want to keep the car in top shape.
MSD as I said earlier is one of a number of brands of electronic ignition system that features multiple spark series and capacitive discharge. I'll focus this discussion on the MSD system, quite simply because it is the best. If you are going to buy this sort of thing you can't go wrong with MSD- performance, reliability and motorsports use. A quick visit to the MSD website will fill you in.
The good stuff then. All MSD's from the cheapest 6a unit to the most expensive programmable Digital 7, work in the same way. The only difference would be the toys that come with them, well get to that later but first the basics of the MSD system. At lower RPM's the spark plug is fired multiple times, over 20 degrees of crank shaft rotation- vs once in the stock system- to ensure complete and through combustion. Above around 3000 RPM this becomes just one powerful spark since according to MSD's literature there is not enough 'time' to fire the sparkplug more than once at higher RPM's. MSD ignitions are also capacitive discharge systems. They are hard wired with a capacitor straight to the battery which can instantly recharge the coil ensuring full power sparks all the time. Quite simply put the MSD is like an ignition amplifier; taking the 12 volts of the electrical system up to around 600 volts then sending it to the coil to be taken up to around 40,000 volts. Compared to more or less 400 volts that is going to be a huge difference. Everything becomes better. From cold starting the engine, throttle response, top end power and low speed driving. Don't think of it as something just for speed freaks too. Even a bone stock car will benefit from this. We have a friend in our car club who has the basic MSD 6a on his mostly stock L-type Lancer and it runs sweet. Just like a modern car. Idles super smooth at around 800 RPM it saves gas too. My engine with the Works Rally Cam and side draft carb used to be a pain to cold start, specially after it had not been used for a while that I would sometimes drain the battery trying to wake the beast. With the MSD it's one click cold starts every time. I also got my fuel consumption down to something very much acceptable for a race engine with a long duration cam. Nothing great, but it is better than what some people get out of stock setups. Another benefit of using an MSD is that for you won't beed a condenser anymore- the MSD will act as one big super-condenser for the electrical charge. The contact point will last much much longer because it will just be a trigger for the MSD, unless you spring for the more wickedly awesome crank trigger setup in which case you won't need a distributor anymore.
More expensive MSD units come with more toys to play with. I use a MSD Digital 6 plus on my car. It has the same basic features as the basic 6a but with digital technology using a RISK microprocessor for more accurate control of it's multiple sparking and other features. On top of that it has a step retard, for setting a secondary timing curve that allows to run a much more advanced mechanical setting for better low end performance, and then with an optional RPM activated switch, retard the timing at a preset RPM by a preset amount to boost top end power. It's also got two step rev limits- an upper limit to protect the engine from overrev damage and a lower limit that can be used as an RPM launch control. It also features a 20 deg. starting retard function up to 850 RPM which is very helpful in staring high compression engines. More expensive models or the optional timing computer will let you plot a timing curve for each particular RPM pretty much like a stand alone compute for the ignition system.
I have been running the MSD setup for over a year and I love it. I was late in the game for this one as my good friend and tuning mentor had been telling me to put one in for the longest time, definitely an MSD should be one of the first modifications you make. Together with a good set of Ignition Cable and some good Iridium spark plugs you'll have a great ignition system. The MSD system is so good that when I blew my engine, I actually could drive around normally as if nothing was wrong even with only 3 cylinders running because of the MSD. A lot of people who ask me about this are usually put off by the price. Locally purchased the MSD 6a will cost about 20k pesos new, however with due to the magic of the internet and with some creative shipping methods you can actually get a Digital 6 unit like mine with a E-core type dry coil (more reliable than old oil filled coils) for about 15k pesos from the US (although when you go crazy with the toys that will go up). Put into perspective an MSD will not cost you more than a set of nice alloy wheels or an entry level sound system- and the benefits as mentioned here will make the investment in one worth every cent paid. Most people just don't realize it and the funny thing is that you won't appreciate the benefits of having an MSD until you have it- then you can't live without it.
This is mounted inside the car, under the dashboard to protect it from heat, because in our tropical conditions the heat in the engine bay can be too much and cause the system to shut down. There are some who claim to have had reliability problems with MSD's but that is because they mounted them in the wrong place.
Remember, as with any type of tuning the basics have to be covered before you start.
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