i want to get everyones opinion on which, if any msd box to get. i have no clue what to get for the box. i like to floor it from one light to the next. and quick acceleration on the highway is very improtant to me. i dont want to go all out on a msd7 because its kinda expensive. what do the rest of you think?

 

I went with the 6A, its cheaper, and all you gain with the 6AL is a rev limiter. The truck already has that. The offroad one focuses on idle to 3,000 rpm. If you get on highways like I do, then your above 3,000 rpm. The 6A, along with msd 8.5mm wires and a blaster 3 coil, made my truck more responsive, and it revs a lot quicker in neutral. I've been real happy with my set-up.

 

at hughesengines.com you can get the box along with everthing else for like $325 which i think is a good price

 

None....save your money... coil and wires i would do.
3 grand on highway ? you driving with O/D off ? When im on the highway i pull 1800 rpm.

 

This is a good question, I have been wondering the same thing. I have been leaning toward the 6A, but recently saw the Offroad in a magazine and wondered about it too. Hopefully other will chime in so we can get some other opinons.

 

offroad is nice because all of the electronics are potted (i.e. more vibration resistant) and it includes the weathertight connector, which is awesome if your rig sees a ton of mud/water/snow bashing. Having said that, since mine is mostly a tow rig/pavement princess (4x4 is used in the winter, and 3-4 times a year on easier 4x4 trails) I coudn't justify the extra price. So I went with a 6A. You should examine what your intentions for your rig are, then make your decision after that.

 

I said "get on" highways. Meaning when I'm on the on-ramp, getting on the highway. Not while I'm crusing down the highway. I sit around 1800 between 70 and 75.

 

the offroads are better sealed and have a gel coating to water "restist" the circuit boards.. mainly makes it so you mount it ALMOST anywhere without worrying about getting it wet.. obviously you can submerge it..

my write up for my 6A and Blaster3 coil install https://dodgeforum.com/m_405881/tm.htm

coils and wires do make a difference.. i can tell a little difference in the butt dyno.. and it sure as hell revs alot easier and the motor seems to be "woken" up after the install.. i like mine.. been running it for almost a year now with no problems

you DO how ever burn up plugs caps and rotors 3X quicker.. so be prepared to change them with every or everyother oil change..

hope this helps

 

Are you serious???? New plugs, caps, and rotors ever 3000-5000 miles????

 

Yes you have a rev limiterbut on a stock computer&MP PCM the hardlimiter is set for 5k or 6k and is not adjustable. If you dont have the valve train to supportthe MP PCMrpm limit and over revgood chance you willdamage things. Hard limiters cutthe spark and when you back off throttle and the rpm's drop, they fire again and there is a good chance of a backfire. Backfires at redline can cause stretch in your timing chain and damage the headgaskets. The msdis a soft limiter & is set with a plug in pill (6al/Offroad)in 100rpm increments. Asoft limiter will cut various sparks then fire them the next rotation to stop fuel loading and backfiring that hard limiter will cause.

Is the soft rev limiter worth the extra cost? It is if you run it to redline a lot and want the motor to last

MSD 6a ($185/Summit), 6al ($236/Summit)and Offroad ($255/Summit) all have multiple sparks up to 3000rpms. 6al has a soft limiter and the Offroad(waterproof) is also available with it.
Require 1amp per 1000rpms
Supply 105-115mj per spark at 460-480 volts primary and 45000 secondary (w/blaster coil)
Sparks fire for 20 deg of crank rotation below 3000rpms

I went with the 6+ in my Indy cause its more of a drag racing ignition.
MSD Digital 6 Plus has multiple sparks to 3300rpms ($318/Summit)
Requires only .7amps per 1000rpms so reduces draw
Supplies 135mj per spark at 535volts primary and 45000 secondary.
Spark fires 20deg of crank rotation below 3300rpms

Has starting retard to take it easy on starter/flywheel/engine when firing it up. Polyurethane potted for increased waterproofiing (not quite as good as Offroad). LED displays trigger or charging issues. Has tach signal output. Comes with rotary pots for adjusting the rev limiters so no pills needed. Has nitrous retard &2 stage soft limiters. The one limiter is for redline but the other is for the start line. Holding a switch feeding the box a 12 volt feed willengage thelow rpm limiter. In my case Ill set it at 3700rpms so Im just below the torque convertors stall rpm. Hold the gas peddle to the floor and just release the button as the 3rd yellow lights and shes off lifting the wheels for 50' (dreamer lol).

MSD Digital 7 Plus has the same features as the Digital 6 Plus above but is stronger and costs a lot more. ($582/Summit)
Requires 1.1 amp per 1000rpms
Supply up to 190 mj spark at 520-535volts primary and 40000 secondary
Spark fires for 20 deg of crank rotation below 3300rpms.
Expect this one to really eat caps and rotors fast.