MSD not LSD

[brett25]

hi guys, i need some guidance as i install an MSD 6A ignition into my 1987 944. two things:

-where can i pick up the green and violet wires (MSD trigger wire) from in my car?


-where can i tap into a red 12v switch (ignition) wire in my car?

-which schematic is me? distributor/crank or points/amplifier

everything else seems to be no trouble. if anyone has experience with this and can answer these questions, i thank you very much indeed. i will post an update on how much performance gain i find with this system
Brett

[drew1]

Hi Brett,

Haven't put an MSD on a 944, but plenty have & you may can find them under search. I'm going from memory from doing points & distributor pick up.

Green & violet pickup? I think this is for the distributor with a pickup or an MSD crank pickup from putting magnets in an aluminum flywheel, etc. I would consider using a point trigger instead. There is just one wire to trigger the coil on a 944 (ter 1, green I think). I would go to this wire on the point trigger.

red 12V tap into ign switch? The black wire on the coil (ter 15) is hot from the switch (tap here as point hook up). I think I rember two big red & black wires from the MSD box that go directly to the battery +12V & ground.

Schematic? Not having them in front of me I'd say the points because you have the wire hooked to old coil +12V wire & another to the old coil trigger wire.

CAUTION: Be careful with wireing hookups so you won't hurt that Motronic DME. If I was doing this I would ohm across the MSD wires that I was hooking to the old coil wires to make sure I got the same or more resistance so I wouldn't be putting too much current on the firing circuit of the DME.


drew1

[brett25]

WOW thanx guys for all the replies!

[drew1]

You're welcome.

drew1

[brett25]

i was being a little sarcastic, but i thank you very much drew for your reply. i dont think im going to put the MSD in my car after all
Brett

[drew1]

brett,

Noticed the sarcasm. The reason you didn't get many replies is that it is hard for people to remember what wires they hooked where. The DME makes hooking up things a little scary, since it is so easily messed up. Nobody wanted to cause you to mess up your car.

I think that the MSD wouldn't be very beneficial to a stock 944, anyway. As long as the stock setup burns all of the gas in the cylinder you're fine. The MSD boxes are good on motors with regular point coil ignition, carburators, high compression, high revs & maybe big cam. It helps with burning excess gas a speeds where the carb isn't too effieceint & has a more powerful spark for high compression than a single point coil setup. The 944 DME ignition / injection is pretty effienct throughout its range, although the extra spark could help starting on cold days.

For a Porsche with a burnt out Bosch or Permatune CD, I would consider an MSD because of more modern electronics & cost.

Saw your post on coils. I'd say stick with stock. I'm not a scientist so I won't get myself confused talking about amps, ohms, volts, & joules. It takes so long for an inductor, winding of the coil to get a charge. When the winding is grounded it puts the charge on the spark winding, kind of like an alternating current transformer the voltage is higher in the spark winding. The stock coil is made to have a full charge at max rpm without pulling too much current from the DME. The real big hot rod coils are made for dual point setups where a set of point closing overlapped and more time to charge. They might not be as good with a stock ignition. An MSD or other type CD box, uses a capcitor & gets a big charge straight from the battery so can use a bigger coil.

drew1

[brett25]

thanks again drew,and as you have shown here, its not the quantity of the replies, but the quality that is important. yes, im going to sit tight on the ignition upgrades. i will do a major tune-up and replace my plug wires with jacobs and thats all. thanks much
Brett