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what is a MSD 6-10 ignition?

2K views 13 replies 6 participants last post by  350c10 
#1 ·
I am currently building a big block for my corvette, and to keep the original tach I decided to use a MSD pro billet distributor with the tach drive. I guess I'm just not familiar with this type of ignition; it says to use a MSD 6,7,8 or 10 ignition. What exactly is a MSD 6-10 ignition? Is this the coil or do I still need a coil besides? If it's not the coil what the hecky does it do? The whole setup seems very expensive, are they any better than a GM HEI?
 
#2 · (Edited)
bigwildgrin said:
I am currently building a big block for my corvette, and to keep the original tach I decided to use a MSD pro billet distributor with the tach drive. I guess I'm just not familiar with this type of ignition; it says to use a MSD 6,7,8 or 10 ignition. What exactly is a MSD 6-10 ignition? Is this the coil or do I still need a coil besides? If it's not the coil what the hecky does it do? The whole setup seems very expensive, are they any better than a GM HEI?
The MSD ignition "boxes" are electronic ignitions that provide multiple sparks to your spark plugs below about 3000 rpm on an 8 cylinder engine. At 800 rpm each plug fires about 3-4 times instead of one. This reduces cylinder misfire due to faulty mixtures. A coil is still needed to make the spark to the plugs. Use an entire MSD system as their components are designed to work together.

The reason that there is only one spark at higher rpms is that the engine is running so fast that there is just not enough "clock time" for more than one spark to occur.

Having played with an MSD on the car... we energized the box without the engine running and had the coil wire sparking to ground. The box creates a constant buzzing of sparks that sounds like a giant bumble bee, will jump a gap of more than one inch, and creates a blue plazma corona the diameter of a pencil that will make a grown man jump. Caution... do NOT let it get you..... It is much-much worse than a police tazer gun. MSD race boxes can kill you.
 
#3 ·
I haven't heard of anyone ever dying from a MSD or being incapacitated from such.

Big, all you need is a standard MSD 6 box and a blaster coil for the distributor. The only upgrade I'd suggest is the MSD 6 box with the rev limit chips. The higher series boxes have additional features that I suspect you don't need and are also much more race applicable.

The MSD site does a wonderful job of explaining all their products.

Is it better than HEI? On a stock type application I'd say you'd be hard pressed to notice a difference to equal the cost. On a high performance application it's a nice to have setup. On nitrous applications it's very wise to have a upgraded ignition system.
 
#4 · (Edited)
xntrik said......MSD race boxes can kill you.
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Rick WI said:
I haven't heard of anyone ever dying from a MSD or being incapacitated from such.

QUOTE]
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http://www.msdignition.com/1ignitions.htm
MSD race units put out from 160-700 mj at 50,000+ volts PER EACH SPARK and about 200 sparks per second.

I don't think that I would want to have that arc through my heart, head, or even toes.... :sweat:


http://www.newton.dep.anl.gov/askasci/phy00/phy00205.htm
"1 joule = the energy generated when 1 ampere of electrical
current, passes through an electrical potential drop of 1 volt. Energy =
Volts x Current.
1 watt = 1 joule/second.
So joules is a quantity of energy, and watts is the RATE of generation of
energy. Watt = Energy / second."



http://hypertextbook.com/facts/2000/JackHsu.shtml

Cutnell, John D., Johnson, Kenneth W. Physics. 4th ed. New York, NY: Wiley, 1998. "Currents of approximately 0.2 A are potentially fatal, because they can make the heart fibrillate, or beat in an uncontrolled manner." 0.2 A

Carr, Joseph J. Safety for electronic hobbyists. Popular Electronics. October 1997. as found in Britannica.com. "In general, for limb-contact electrical shocks, accepted rules of thumb are: 1-5 mA is the level of perception; 10 mA is the level where pain is sensed; at 100 mA severe muscular contraction occurs, and at 100-300 mA electrocution occurs." 0.1 - 0.3 A

"Electrical Injuries." The Merck Manual of Medical Information: Home Edition. Pennsylvania: Merck, 1997. "At currents as low as 60 to 100 milliamperes, low-voltage (110-220 volts), 60-hertz alternating current traveling through the chest for a split second can cause life-threatening irregular heart rhythms. About 300-500 milliamperes of direct current is needed to have the same effect." 0.06 - 0.1 A(AC) 0.3 - 0.5 A(DC)
:thumbup:
 
#5 ·
A lot less Voltage/Power than that "can" kill you. I have been shocked by hi output ignitions and I am still kicking. It all depends on how and where you get shocked. It is very possible for a very small shock to kill you if it "passes through your heart". As an electronic/computer/field engineer, we go to classes all the time about how electricity can/will kill you.

I think Rick was pointing out that if you were to take a zap from an MSD, that doesn't mean you will die. Is it possible?, Yes. Probable? No. I would want it hooked to my chest, but taking a shock in one finger won't kill you. Just make sure you don't make a path top ground through your body (heart).
 
#8 ·
Rick WI said:
Xntrik - it's not going to kill you, your wrong on this.... period. I'm not going to argue. I am sure you confused yourself typing all those links as you compare apples and footballs. But I digress.

Geez Rick, what's up?

All I am saying is that the possiblity exists, technically, and trying to give some reasonable basis for saying it.

Damned if you do, damned if you don't.

Maybe we should get some drunk volunteer to get really sweaty, bend him over with his chest touching the core support and shock the **** out of him,,,, just to see if he might die........
 
#9 ·
i can speak from personal experience on msd 6a ignitions, accel 300+ ignitions, mallory hyfire, and an hei with an accel coil. they hurt, alot..............don't ask why i still haven't learned my lesson...........and no laughing!!! but not fatal............although, when i got hit by the accel ignition, my vision did go black for a second...........and i saw stars for a few seconds after........but i'm still here!!! definately not fun to get hit though, and it can hurt you. if not from the shock, the sudden "jerk" away can toss you into a hood, table, etc. where you can get hurt from. best thing is to be damed careful no matter what you have!!!
 
#10 ·
What you originally implied is an MSD race boxes "can kill you". They won't. We live in a litigious society. If there was a possiblity that an MSD ignition system could kill you there would be all kinds of stickers on the coil stating that fact, since it's the coil that controls the total "MILLIJOULES" (that's .001 joule per millijoule) to the plug. In addition we would yearly hear of some death of some hotrodder that resulted in the unfortunate combination of a fat finger holding onto a plug with the other hand grasping the hood hinge while someone else decided to turn on the ignition at the same time.

We would also see many many warnings not only on the boxes themselves but plastered all over the website as well.

Also, we are talking about DC circuits, with less than 1 total watt of power. DC shocks are typified by a shock and release event. In other words with DC accidents the "victim" releases right away. That is the nature of DC. Typically no harm no foul unless you bump your elbow.

We also forget resistance, which in a human body is what, 2,000 to 500,000 ohms. Even at a very low 2000 ohms the amount of current that will hit your body is well under that which will kill you. Just consider your battery and assume you dead shorted it through your body. It has say 240 total amps available. It's of course limited to 12 volts. So using Ohms law we have 12 volts through 2000 ohms resistance and we have .006 amps into the body, far below the .1 ma that usually will cause your heart to....have issues. Even if you have wet skin and a decent path it still puts the current at .012A.
The point being is the resistance of your body is the key that allows you to survive a shock like this with only a jolt.

The other issue is time. Time will degrade the outer skin and therefore reduce this high resistance layer. A 50ma shock burns but won't kill, unless you stick to it for say...about 3 seconds. Then the current flow increases to about 250ma and your kind of toast. Now, that's a typical senario with AC voltage where the tendency to "stick" can be quite high. you don't have this with DC cicuits.

I have been out of the electrical engineering business full time since 1995, which prior to that I worked at Alliant Energy as an Industrial Engineer for 15 years. I worked around voltages as high as 12,470 real up and close like and on a regular basis with 277/480. Service sizes varied between 200 amp up to 4000 amp switchgear. I know exactly what will kill you and how and what you do to protect yourself. When working on my ignition system I don't go into the trunk of my car and open my bag containing my rubber gloves, sleeves and leather protectors to check for spark. I will use them when I am setting a kW, Power Factor, Harmonics meter, on a 120/240, 120/208 or 277/480 volt buss bar, or fixing the 3 phase converter in the shop.

Lots of folks are nervous around electricity. A quality leather glove, in new condition, will protect you from shocks on low voltage/low current applications like we run across on our cars.
 
#12 ·
I don't want to turn this into a arguement or split hairs. DC electricity is far more dangerous than AC. With DC if you get shocked you can't let go (not talking about an MSD which on the coil side is not a constant voltage). The MSD DOES carry enough current to kill you, the chances of it happening are slim, BUT please don't think it can't happen, cause people have died from less of a shock. The shock itself is not what will kill you it's the heart failure or stopping from being "short circuited". People get hit by lightening and many people live, many don't so you can't say lightening won't kill you, that is just not accurate. You are not going to die from getting your finger popped with an MSD or other auto ignition. Now make a path to or through your heart and it "can" easily kill you or cause you to die. I worked on large commercial systems (telco -48VDC) you would think only 48volts, well let me tell you it will kill you in less time than it takes you to blink. It's not the volts that get you it's the current (amps).

Rick, I see your point and it is valid, but you have to assume you are talking a bout a healthy adult. It you have heart problems less voltage/amps could kill you.

People die from getting zapped with a "non-lethal" stun gun all the time. It depends on the person.

It is not worth argueing over, you would have to try real hard to kill yourself with an MSD or other auto ignition.
 
#13 ·
Camaroman, DC does not exhibit the "stick" you refer to, that is AC.
The term we use in the industry is "The Let Go Thershold". I am 100% positive about that after working in the Utility industry for 15 years as an engineer, attending UW Madison and quite a few post grad classes in electrical safety. AC voltage, if high enough, will cause you to stick to the short. 480V is especially prone to this if the fault current is not high ehough to blow you off the fault.

The documented threshold for heart fibrillation is around 100ma, well below the shock limits we are looking at in these low voltage applications. IEEE has done exhaustive research on this over the years as has OSHA and others. Sure, there is that one in a million poor sucker out there that gets hit by 50ma and dies, where a typical person would simply be knocked silly but survive. We are not talking about the 1 in a million we are trying to clear up an issue that that I disagree on that an MSD can kill you.

Again, I go back to the basics, look up ampacities that cause mild shock to severe burns on up to death and use ohms law to calculate current flow given the voltage and resistance in the human body.
 
#14 ·
xntrik said:
The MSD ignition "boxes" are electronic ignitions that provide multiple sparks to your spark plugs below about 3000 rpm on an 8 cylinder engine. At 800 rpm each plug fires about 3-4 times instead of one. This reduces cylinder misfire due to faulty mixtures. A coil is still needed to make the spark to the plugs. Use an entire MSD system as their components are designed to work together.
You can buy more expensive MSD ignition boxes that can make multiple sparks through, I think, 6000 rpm on a V-8. Go get a Summit Racing catalog, if you don't have one, and look at the ignition boxes. It will tell you the specs on all the boxes.
 
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