MSD6A--fact or fiction

[brent]

Well, after the new tires this Friday, the next two paychecks go into gettin the stuff for the TFI upgrade. If anybody's ignition sys could use an upgrade it's mine. That being said, here's all the bad things I can recall from previous threads:
1)It blows up real good.
2)Extremely sensitive to heat. So sensitive keeping it under the hood is a bad idea.
3)Many people here have gone through 3 or 4. At 160 each, I can't afford that and I don't know how you guys could've.
Thanks for any guidance, Brent

[rockjeep44]

My MSD offroad box rocks but like you said it's gotta be set up right. After sticking it inside the truck I've had no problems. I burnt up one under the hood but I swapped it out under warranty without trouble. They spit out one heck of a fat spark which is nice.

[Heimeken]

Brent, I am very happy with my setup and I have totally trusted it for over 2 years. I have it under the hood with no problems. I know that there have been some bad experiences on the list with the off-road units (I have the regular 6). MSD is still one of the best units out there and percentage wise still very dependable. I think most problems are connection related, specially since most of our rigs have been modified before the MSD. Take your time and do it right and I think u'll be OK. Like andrew side. It's a powerfull spark. I know from experienceing that jolt through my body!

[zomotropin]

just curious but has this been a problem for the MSD 5? i just got rid of mine and i want to prevent any problems for the person i sold it to.

[nhl77]

I have the MSD 6a box and have no complaints. It has been on of the best performance mods I've made. I think the only thing better was a new motor.

[Bridge]

And what happens when the MSD goes out? Total shutdown? Return to stock coil performance?

[89grand]

I've got a 6A mounted under the hood and so far everything is fine. I also noticed better throttle response and idle with it.

[Heimeken]

Bridge, if the MSD shuts down, usually that is end of the day for you. Unless it is a heat build up problem where it will start once it cools off, you would have to replace the box or go back to the stock setup. But that is pretty much the case in all electronic ignitions.

[ July 30, 2003, 09:22 AM: Message edited by: Heimeken ]

[Joe Guilbeau]

The MSD (Multiple Spark Discharge) is a pretty rugged unit.

I believe that most of the problems associated with the box centers around not providing enough amps at 12Vdc for it to operate correctly.

I believe that I read somewhere that it can draw 35 Peak Amps during operation.

Take care of it, and it will take care of you.

[Puvong]

This MSD box is worth every peny that I spent and have been using it for more than two years under the hood without any problem.

[Joe Guilbeau]

I have come across the Schematics of a MSD-6A ignition box, with brief (electronic technical details) if anyone is interested in looking deep into the bowels of the beast.

This guy reversed engineered the ckt board and includes a schematic and values.

Essentially the box is is a timing circuit that controls a Capacitive Discharge circuit.

He fed in a square wave to simulate the tack trigger, and found that at...

800/RPM's.............3 discharges per second
1,275 RPM's...........2 discharges per second
2,550 RPM's...........1 discharge per second

Anyway, the details are at the US Patent Office and available for anyone to review...

http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=/netahtml/search-bool.html&r=2&f=G&l=50&co1=AND&d=ptxt&s1=4,131,100&s2=autotronic&OS=4,131,100+AND+autotroni c&RS=4,131,100+AND+autotronic

[Puvong]

Hey Joe! Thanks for the link, that's a good one I must read.

[Bob Barry]

I've had mine on my GW for two years now; it's helped out low-speed driveability, but it's not a new revelation. A good-running Duraspark II system with the TFI upgrade is easily 80% of what an MSD is.

I left the original Duraspark system in place, and bypassed the original wiring with a distributor harness adapter from MSD and Weatherpack connectors at the coil. If the MSD ever fails, I can swap back to the stock ignition system by changing two plugs.

The real advantage to the system is the MSD adjustable timing advance control that I added. I can run anywhere from 0º to 15º initial advance, and adjust it from the driver's seat. It's the greatest thing when you're getting a bit of ping on long hauls due to spotty fuel quality.

[Chuck]

I did the TFI upgrade about 4 months ago, and am very happy with it. I am also getting ready for the MsD6a, are there adapters availble for the electrical connections, or do I have to cut wires and rewire. If their are connectors available, does anyone have the part#'s.
Thanks, I don't post much, but enjoy reading all of the good info.
Chuck

[Puvong]

Chuck, you will get more detailed info on this link: http://www.ifsja.org/tech/electrical/ignitionupgrade.shtml