Is the MSD ignition box necessary?

Always wondered about this. Or are they for those who are building performance engines over mild street motors?

 

Ok had this arguement once before and from my experience for a mild street build they are not necessary.But a high compression high rpm engine is where they will make a difference.
My mild 460 had a duraspark in it changed it over to all MSD, distributor,box and ciol and it didn't make a stitch of difference.Ran it at the dragstrip before and after it ran the same.

 

same here...dynoed it on and off...everything the same...

...:Handshake...

 

Ran my car with it/w/o it, both on the bottle and off. NO noticable difference.

 

I've read that the MSD will smooth idle and improve fuel mileage? Can anybody confirm or debunk these claims?

 

In another post, Dan Starnes (I think) endorsed getting a box with the rev limiter as it saved his engine when he had a transmission failure.

 

My 331 is fine with the stock Duraspark box. And seeing as how this box was put on by a previous owner, that even more speaks for it's effectiveness.

 

Msd is good but not necessary. I use one for the rev limiter.

 

I have an MSD 6AL on the Sprint.The 351 has a rorty cam some grunt and healthy compression.The car also has an MSD ready to run distributor.On the dist alone the car runs good but fuel consumption is in the 10 to 12 mpg range along with what feels like a soft midrange pull.On the 6AL the fuel consuption is in the 15 to 17 mpg range and the mid range pull is way better (You can actually feel that its on the cam) above 2500 rpm.IMHO... If you are running stock heads/pistons with a crummy burn efficiency,the MSD will help "a little" as far as fuel burn/economy is concerned. As for high performance engines where ignition performance needs to be optimised for boost or nitrous a cd box should be prerequisite.For mild/stock engines factory ignition systems will keep up just fine.The problems occurr when the engines RPM exceed the ignition systems capacity to saturate the coil and create a hot enough spark to fire the charge in the cyl.Properly curving a stock distibutor and getting the timeing dialed in for the engines needs/ability is half the battle.Ultimately...The whole system has to work in concert,all the parts have to be chosen/orchestrated to achieve the goal...In this case, Power output.

 

That is the main reason i use one.When something lets go when you foot is on the carpet not much time to react.

 

some of them also control timing don't they?

 

As far as controlling timing there is an add on box with a switch that mounts inside. You can adjust the initial timing about 7 degrees each way I think. I used one when I had the higher compression 351w in my truck. If I got some bad gas I could dial it back and get rid of the spark know. Some of the pricier boxes might have it built in.
When MSD claims it will help smooth out idle they are probably comparing it too a points type ignition where it probably will run better.
clitn

 

So if I'm looking for something to make spark more reliable to a stock or mildly upgraded (eventually) engine you recommend just getting the MSD distributor, plugs and coil only? I was thinking of getting it all but if I don't need to I can save that extra $150 for something else.

 

I run a 6AL and Blaster II TFI coil on my stock 200 I6... Noticeable improvement in power and fuel economy around town. Seems to have a little more torque overall. I just put it on to aid in efficiency.

Also just picked up a 40th anniversary 6AL for the hell of it because I like the way it looks, and they're only going to make 4,000 of them. Don't even have anything to put it on. Just going to shelf it for now.

 

Hey Jamie. Is that difference between a points dist. or a dura spark set up?
clint