Hey yall I was doing some more reading about MSD ignition and every thing seems to be good i've read about it but I was wondering how much better is it then my HEI's I have on both of my trucks I know they have fancy stuff like Rev limiters and advance timing features but I read allot of stuff about how it they can put a end to running rich better MPG big Hp gains is any of this true or just the marketing i've never owned one obviously dose any one own a carbed enging with MSD ignition did you see any kind of real gain.
I ask because No matter what I do my truck all ways burns rich I've tried jetting down as low as Holley makes jets no vac leaks I can't no sigh of leaks but still she burns fat could a MSD help in this area or could it be some thing else i'm missing
The engine i'm talking about is a 302 all stock other then intake headers Holley carb and Profrom HEI.

An MSD box basically increases the duration of the spark at each plug, in a stock engine you will see very little benefit. In a high performance application you can squeeze a little more Hp out and/or eliminate ignition timing problems that can occur in a racing motor.

Here is a link to a general overview of what occurs during the spark sequence in an engine.
www.centuryperformance.com/spark-plug-tech-spg-26.html

If you are using a exhaust analysis to determine if you engine is running rich, there are several things that can cause a rich condition. Poor air charge flow, poor cylinder scavenging, poor ignition timing control, carburetor worn out, worn engine components, restricted air intake, ambient temp, fuel quality, the list goes on.
Bottom line even in a properly running engine it is very difficult to get a carburetor to provide the correct amount of fuel under all operating conditions. This is the main reason all of todays engines are fuel injected along with being computer controlled.

Thanks BlackHat I think it might be time for a new engine..... i've just had to many issue with this one..

TexasNomad said:

Thanks BlackHat I think it might be time for a new engine..... i've just had to many issue with this one..

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How many miles on the engine? Is this your 1979 5.0 were talking about?

Under 100,000 it lacks power there is lifters going out it has a shudder that nothing can fix or make better and the engine all ways runs rich no matter what I do or tune it just stays rich whats what I getting for having my engine rebuilt in this crapy town.