msd box

[hansj3]

hi i have looked around the forums and have not found anything as far as what a msd box will do for mileage i can get a msd 5 box for under $100 and i was wondering if its worth it.

i have a 96 jeep with the 4.0 and when i am not hauling my boat i can get up to 22mpg on the highway.

[jamesqf]

Maybe if you told us what an msd box is, someone could help.

[hansj3]

multiple spark discharge . under 3000 rpm you get up to 8 separate spark events within 20-30 degrees of crank rotation standard boxes are less though. msd6 msd6al msd5 are all common model numbers

[gone-ot]

...MSD™ used to do wonderful things for hp and mpg back in the days prior to smog laws and no-lead gasoline.

...today, it's not much better than current OEM ignition systems, especially the "on-cylinder" coil ignition systems.

...between 1973 and 1981, I taught a college course, "Electronic Ignition Systems," and it was one of the units discussed. Great back then, but not really so today.

[hansj3]

Thanks fot the input... I know my jeep has the best ignition 1987 had yo offer when they first designed it, I was just hoping for something easyier and cheaper than a megasqurit that would net me maybe one to two mpg

[gone-ot]

...aerodynamics and driving technique will net you more than changing ignition systems...unless what you have now is not working up-to-par.

[JasonG]

If its points, look for a hall effect kit for the distributor.
The chevy HEI can be swapped into many cars with a little tinkering.
Toyota distributor guts can be had for ~$20 as well.
if it has electronic ignition, the difference will be impossible to tell.

[30mpg]

they amplify the spark so it should help burn the mixture more completely on an older car.