What do msd 6a boxes do?
 

people say it smoothes out power below 3k.... multiple spark discharge etc...

what are your opinions on these?

I have no experience with them but MSD's web page says

"... the powerful multiple sparks of the MSD 6A will ensure complete combustion. Benefits such as quicker ET’s, easier starting, reduced plug fouling, more power and even increased fuel economy can be expected with the 6A’s high energy multiple sparks."

I have experience with them.....specifically a 6 AL.
The 6 AL has a chip to set a soft touch rev limiter.....available in 100 RPM increments, externally installed....which is nice, but not earth shaking.

What the MSDs do best is provide fire...lots of it.....when used in conjunction with one of their hot (40000+ volts) coils.
The 6AL provides this voltage in the upper rpm regions, where as other (OEM) CD units can't.

In pratical terms this means one can gap plugs up to about .05 (tho I use .045) and it will fire that gap throughout the RPM range (multiple spark below 3K).

Seems like a lotta nothin' eh? It is IF you don't need it.
A well maintained EFI really doesn't, but if you're running carbs and long duration cams......it's a Godsend. No more fouled plugs and your rich running carbs pull cleanly throughout the RPM range.

I dicked around for about 6mos trying to get my new motor to run clean. Put on the MSD setup.....end of problems. 8.5 mm plug wires are a good idea also.

Next time you watch a NASCAR in car camera, look on the dashboard of the car. Great advertising for MSD:D

A buddy of mine (more'n a handful of years back) who is an engineer and racer once told me "MSDs are mostly useful so that idling doesn't foul-out your high heat range spark plugs that you need for racing." That was his take on it, at least.

I know others who claim smoother operation at moderate RPMs, particularly with aggressive cams, carbs, and rich mixtures.

--DD

I use a MSD box in my 2.0L series car. It starts easily and prevents any missing at high RPMs which can be a problem with hot rodded sixes. You will need their coil and 8mm, 8.5mm or larger wires as the spark is about 15K volts at idle and mine reads 36k volts at 6k RPM. I did not get the rev limiter as it does not prevent over revs when you select the wrong gear such as 2nd instead of 4th. As you can imagine my plugs never foul.

thankjs guys, but, heres the question now. can i use it with a mallory unilite distributor?

also...anyone have a diagram of where the wires go on install?
i have a 2.0 high comp, hit cam'd 4 banger.....

The MSD box will work with any distributor as long as you know what wires on the distributor do what. On MSD site they used to have all their users manuals which have diagrams of how to connect it to various systems. Oh yes and when you get it running do not touch the coil primary connectors as they have a tad more than 12 volts. Good luck

Anyone know if MSD makes a wiring harness that works with the 914 setup, assuming it's any different than any other setup? Got a p/n for it and maybe a picture of a nicely installed MSD system...may car has the MSD that the PO installed and wires are spliced and connected in all kinds of ways and places, I want to straighten out that wirey mess. Have any idea how much said harness might go for, before I call?
Also, the tach does not work in my car - is this because of the MSD system and if so what needs to be done to correct this problem? TIA!

Doug C

The easiest way to figure out what is what is to get the diagram(s) from the MSD site and then look at the color codes they use. I think they use the same colors for the same things on all the boxes. Then look at the wires where they are connected on your car, I.E. coil connections (2) electrical to the MSD box, etc, etc. Then you can match what is going where and in some cases there will probably be several wires connected together(on my race car I have two connections with 4 wires each). As for the tach I think you need their adapter to use the stock tach?! It has been a while since I hooked mine up and I now use an Autometer tach. Good luck

Thanks John, I saw some nifty connectors on their site but was just wondering if anyone here had gotten one for the 4 cyl 914. I'll ask about that when I get around to calling and inquiring about the Tach adapter that you suggested I would need.

Doug C