[massey478]

AZKen, I am also referring to stock motors in my advice and not mixing the two. You do not have to spend the high dollars for the new MSD system. There are good used ones on Ebay. Read the Bosch fuel manual about the alcohol blend fuel. It states that the alcohol in the fuel attracts some water which, when present in the fuel charge, causes the mix to be harder for the ignition system to ignite, so enhanced ignition systems are a good idea. After sitting long enough I have had the blend fuel phase-separate. This is really ugly to the point you have to drain it and throw it away. Putting some of the drained fuel in a glass jar, one will actually see two layers of liquid! Also a factor in this is that many of the vintage trucks folks on here own are not driven regularly so the alcohol blend fuel draws even more moisture, too often to the point it rusts the bejeebers out of the fuel tank and corrodes the carburetors, giving even worse problems. Also, now we have computer control on all of the modern motors. It automatically controls spark advance and fuel rate to optimum conditions with knock sensors and exhaust mixture monitoring. For this reason we do not notice the difference caused by the alcohol blends. We do however have to make modifications to the older non-computerized systems on our V-6 and other older stock motors motors to give them the best performance we can in the absence of computer monitoring and control. This is one of the reasons why the enhanced multi-spark system helps. I have not put the MSD system on any stock motor that it did not immediately make a noticeable difference in idle quality, starting ease, and better performance. This is not bad advice and it definitely for me has not been a waste of money. Also you mention vacuum leaks causing power loss. They affect idle quality, not top end, foot on the floor performance. This is because intake manifold vacuum is at its maximum at idle when the carb throttle plates are closed, a condition when the vacuum leak would be most noticed by evidence of choppy idle. When you have the throttle plates fully open under full power, the vacuum in the intake drops to a very low reading. Because of this fact, the effect of a vacuum leak is minimized at full throttle because the manifold vacuum is not there to make it as much of a factor if at all as well as the air volume going into the motor makes the vacuum leak a very small percentage of the total flow. The vacuum leak would have to be large enough the motor probably would not idle at all to affect full throttle performance in a really noticeable way. I am not pointing this next comment following at you, AZKen, but as for things being supported or not supported on the internet, many times I do not get involved in the discussions and advice I see being given because it truly scares me to see what some post as solid advice. It makes me think "Wow, if some poor guy takes that advice as gospel and does it, bad things may happen!" Internet information is like all things in life, some good and some way off the mark. One has to carefully digest the information and try things on his own equipment in his own environment and way to see what works best for him. I have never seen one of these V-6 motors that bringing the timing forward as I advised and enriching the fuel and enhancing the spark system did not help in a noticeable way. I do agree the HEI system is a very good system but there are ones like MSD that surpass it, in my experience even on stock motors. Ignition point quality seems to be lower now than years ago. Stock systems charge/discharge the coil with the action of the points, putting a high voltage/amperage load through them, diminishing their life. All they do with the MSD system is trigger the system so the load is very low leading to longer point life. I had another brand of electronic ignition, single spark, on my Massey 478 before putting on the MSD. I immediately saw a difference, and still do. As with modern cars, and even back years ago, lessons learned in competition like the drag strips and oval track racing were applied to stock motors to enhance their performance. A lot of work was done at the strip by factory engineers like the Ramchargers for Dodge who used lessons they learned at the strip in testing to apply to their stock motor designs. I certainly bow to them and their likes for their engineering knowledge which I recognize is above and beyond my engineering training, which is in mechanical engineering. My training applies a good bit, but not to the level of factory engineers who work with it on motors as a life work. I take what people like them do and report and learn from it for my own enhancement, going forward to apply it in my way in my environment with more trust in them than what is found many times on internet. That is what I am dong here. All of this methodology I am recommending applied back in the 70's when I worked on these V-6 motors for a living, and now, even more so with the new alcohol fuels and worn motor components. Thanks, AZKen, for your comments and I always welcome good, open, respectful discussion.