I did check my manual and it says .016. There is no way I have the time to do all the different gaps over the years. The new style 1959 235 is the engine under test, so I have to go with the shop manual. (.016/.035)
To me test three would NOT be gapped to a gap designed for a points distributor, high ohm stock coil with ballast resistor and much lower voltage, so no.. HEI is a totally different animal and needs to be gapped to HEI standards. This is because the coil is much hotter, there is no high ohm values or point gaps/dwell issues. The HEI system is NOT just the distributor. It includes the 45kv coil and the HEI modules controls.
You are correct however that the HEI gap has not been totally determined. Not sure which TWO gaps make the most sense. I am NOT going to go to different spark plugs. That adds unnecessary expense to the hobbyist trying to switch to HEI. Your stock plugs will have to do. I have a set gapped to .045 and the electrode is already bent higher than level, so that's why I was thinking .045 and .050, however that is for sure negotiable.
There IS a scientific reason not to gap much further. This is a small body distributor and cap. You cannot gap too far lest you get the fire going the opposite direction instead of jumping the gap. You can also get crossfire and quicker burned out parts. I know from experience the system works flawlessly at .045 and I know from the ignition specialist that longevity of parts is not an issue when using .045. This is the nuance of using the stock dizzy.
If you can tell me the RPM it takes to go 30mph with no load and no transmission or rear end, let me know what that number is. Same for 55. Please let me know cause that makes sense. (although now we are talking about TWELVE tests). I feel idle is just slightly too slow for the test because of the erratic behavior of a points distributor at very low rpm. That's why I suggested bumping it up, but not enough to trigger the mechanical or vac advance. I wish you could be here to see what I am talking about when using a high tech timing light.
The shop is a commercial building with exhaust venting and total climate control. I will be sure to write down the humidity and temp anyway.
Remember that none of those issues matter Jeffrey. The reason is the same I stated for Carl's concerns. Controls placed on ALL tests will give exacting, repeatable results. Sure a rainy day will change the results, but across ALL tests. I will also make sure I use gasoline of the same grade for all tests and make no changes to the engine during the tests. Remember that most people don't drive their vehicles around in a temperature controlled 74 degree environment from point A to point B. So the test is more for the relationship between the tests. If it's repeatable, and I will make sure it is, we will have good data.
Please continue the conversation (and stand your ground on what you would like to see), I am wanting to make this a meaningful test. The results will look really nice in my HEI How-To article.
