mojomal

I’ve heard that the msd 7al-3 may run erratic at lower than 12 volts and should be run with as much as 18 volts is this true? Also I’m assuming that you would have the 18 volts coming in from the ignition switch if this is not correct inform me how it should be connected.

hammertime

Mine has 11.2 volts to the 7al3 no issues lots of myths with these boxes some truths but not all

showbusiness

CAN ANY ONE HELP WITH THIS , WHEN DO YOU NEED TO CHANGE FROM A 6AL SYSTEM TO THE 7 , WHAT ARE THE BENEFITS..MUD DRAG RACING WITH NATURAL ASSPIRATED SBC , NO BOTTLE...

hammertime

I've ran the 6al on my bigger inch bbc with alky on them with no issues at all. The only reason I even switched to the 7al3 is everything is built in for the chips. If what you have is working dont change it. Inscreased spark is what you'll get. IMO if you want to change go digital 7530T

jmarksdragster

Run an alternator and you won't have any issues.

altune

Our cars with less than 12.3 volts runs irratic.
It all depends on your compression and fire needs.
A blown engine under high boost requires much more spark energy that a normally aspirated engine.
The differences on the MSD stuff is more capacitence, the better the ignition the more fire , pretty simple.

mojomal

thx for for all the info.