Ok, so you're truck idles great, and gets 18MPG? I'm just curious how much more driveability can be improved if my mileage is that high and my idle is as steady as it is.
Driveability improvements, in this case, the way I look at it, would be more power, or better idle. Now: More power would be apparent in a dyno test, at any RPM, if more voltage somehow made a difference. It doesn't, and can't be proven under 4500RPM. Since dyno's don't measure (typically) under 2000RPM, what happens under that RPM, power wise, can't really be measured. Which situation is likely to result in more unburned fuel? High RPM or Low RPM? If its low, multiple spark would help. High? Well, from 2000-4500, no proven gains over stock.
Better idle? How many of us actually have the vehicle in tune, and it idles great? Mines one, this I know.
However, I guess I could go on, but people are gonna believe what they are gonna believe. I'm offering a different opinion than yours, but its all cool. The guy asked what it will do for him, I say nothing, you say something. Headers or a cam may not be something he wants to do, but I doubt anyone here will argue that an MSD ignition will give him anywhere near the kind of power increase he would get with either of the other swaps. Heck, besides labor, a cam swap can probably be almost as cheap as an MSD box!
For my next trick, I'm probably gonna run a .060 gap with the stock HEI, just to see if it makes any difference.
Dorian
My tech/links page: <a target="_blank" href=http://www.dorianyeager.com/index2.html>www.dorianyeager.com/index2.html</a>
Why insist on counting when the ring gear has the tooth counts stamped in?