MSD DIS ..anyone using it ???

[turbo nasty]

Is anyone using the 4 channel MSD DIS ignition and interface ?

Is it worth the money ?
What improvments were noted ??

Thanx thought about getting one.

 

[azgn]

I have one.....unless you want to use the 2 step rev limiter, don't waste your money...they seem tempermental to me.....seems my ground hookup is not adequate and mine is intermitent

thye do keep your plugs cleaner on leaded fuel and you can run a wider plug gap

you also need to buy the adaptor plate for our coilpack

 

[ChrisCairns]

Some months ago there was a long thread about the Dis4....the main complaint was the trouble people were having with it. Some had sent theirs back, had it checked out and MSD returned it saying they couldn't find anything wrong with the unit.

I also had trouble with mine missing at high rpm. I returned mine and they did find something wrong and returned a brand new unit to me. It now works perfectly.

As already mentioned, the 2 step is it's greatest feature. The 2 step works by cutting out ignition power sequentially I believe, to limit the rpm the engine will reach. Hence, it fills the exhaust with the unfired cylinder's gas/oxygen mixture. The O2 sensor reads the excess oxygen as lean and fattens up the mix. Now you've got a fat mixture going into the engine on launch.

Usually people who have an MSD box also have a FAST computer or some aftermarket computer, and set it to NOT have the computer correct for this fattness by having the wide band O2 not start sending signals until a higher rpm than launch rpm.

Clear as mud?

 

[TURBOV6]

I have it no problems here . But I did send it once for a problem that was not my fault but it did fry my ignition module and coil pack.

 

[turbo nasty]

any more folks ???

 

[kamarossrs]

the high rpm miss is caused by a weak ground, its very common and causes lots of people to stop using them and blame the MSD,,it had a miss when grounded to the engine,,,,,but worked fine when grounded right to the batt.....overall ive been hqppy with it.......

 

[bob86gn]

I use it, have not raced with it but it does keep the plugs clean with leaded gas. No complaints so far. Install was easy with the adaptor, it is easily deactivated with the supplied jumper. The wiring is prettty important to make sure you are well grounded.

 

[TurboPhil]

OK here is my opinion on the MSD DIS-4 after running it on my car for about 4 years.
I like it, idle is smoother and snap throttle response is faster and back when I was running pump gas at 18psi I was running a .045 gap on my Autolite #23’s with no problem and for about the last 3 years running ERC-110 leaded with the Max Effort 16-pos chip set on race timing at 24~25psi with my plug gap of .038 I have never felt a misfire.
But your wiring needs to be right so per MSD install instructions hook up power and ground to the battery to prevent surges, spikes and noise getting to the box (the battery is an excellent electrical dampener). And you must use real good plug wires cuz if you don’t any Capacity-Discharge ignition system will eat them real fast! And knowing that about a year ago I was bored and wanted to see how my plug wires were holding up on my car so I put my MAC ET2020-V2 lab-scope on the car to check the plug wires and any funny spark burn-lines for other problems. So to get a good baseline to know what I was looking at on the scope I unplugged the MSD and put the bypass plug in and every thing was OK so now lets hookup the MSD and see why the idle and snap throttle is so much better and there it was, 4 spark events instead of 1 spark for the stock system !!!
So do you need it? Probably not but I also like to set the max rev. to 4000 when I need leave my car for tires,alinment or smog tests.
HTH someone, Phil.