I'm looking to get some sort of numbers that can quantify ignition upgrades. I know that points<electric ignition< HEI < MSD system. However, is there any way to quantify this? I'm looking to upgrade my points system and go full MSD, but only if its going to be worth it. I hopped over to the MSD site and couldn't find any sort of numbers that would help me in my decision. Here is teh setup I'm considering:

Distributor: Street Pro-Billet PN 8361
Coil: Blaster 2 Coil PN 8205
Box: MSD 6A PN 6200

However, I'm also considering a Pro-Billet Ready to Run PN 8360. But at $100 more than the 8361, it doesn't seem to make much sesne seeing as the 6A is only $15 right now.

However, if I go with a standard HEI ignition for only $150 or so (Mallory, Accel, or any other good brand), I would think saving $300+ would be a good thing if its only a marginal improvement.

Anybody have any sort of numbers on effeciency? Percentage increases are cool, but I really want to understand the technological jump.

I can not provide any technical data, but I can speak from actual experience:

My previous El Camino (1985 model) already had HEI, but I sort of upgraded by removing the computer and all electronics. I then installed a blueprinted vacuum advance HEI. The strongest point of the MSD is to improve efficiency of the ignition system, particularly below 3000rpm. I will say that i did notice some (marginal) improvement with the MSD, but would add that in my opinion (which is based on very limited knowledge) the MSD is only needed if you have a serious street/strip combo where compression has been dramatically increased.

In conclusion, if you can afford it: go for it. If you want a daily driver with an excellent ignition go with the HEI.

Of course, I will install an MSD6a on my newest acquisition (1980 El Camino). Not because I need it (although I am going to attemt a 375-400hp build with approx 9.4:1 compression); Just because I can.

And isn't that what it is all about?

I'm running a straight billet/aftermarket HEI with vac advance and it's working fine for me. I did add a high performance Excel coil (55K volts, I think). My engine has 9.5 compression. No misfires at either low or high RPM. I'd run a MSD 6A if I had it, but the way mine's running now I don't think it'll add enough performance to justify the money (until I add nitrous or a blower etc).

Best.....