Appreciate some input on spark plug reading
All stuff to try when looking to improve combustion......
How to Pick the Best Carburetor for a Street/Strip Car
Have to laugh when the smaller carb ran quickest and idles best its 425 CI on street fuel:
As you can see from the Dragstrip Test Results chart, our guess that the 650 carburetor might run the quickest of the bunch turned out to have some validity. The smaller carburetor delivered the quickest move to the 330-foot mark and the quickest overall e.t. and fastest mph
I wonder what that's telling you this engine needs......what does the smaller carb do?
It needs to use more of the fuel it already gets......
I'm not saying that a smaller carb can't make a lower ET at the dragstrip but for me the test at the dragstrip they used to confirm this was not conclusive proof. There may be better test out there to use as evidence.
The article is written in a way to make you believe that the reason the car went faster was because of the difference in size of the carburetors. This was stated at the beginning of the article. Maybe this was just hindsight or maybe it was a bit of confirmation bias.
There were many differences in the carburetors. Some differences include choke horn vs no choke horn, downleg booster vs straight leg booster, differences in the emulsion packages, carbs with and without jet extensions, power valve package, carb bowl size, advertised cfm vs actual measured cfm, etc.
Without testing to control for the variables or even ABA testing to control for repeatability the conclusion reached could have also been that the cost difference of the carburetors was the reason for reduced et.
This isn't to say that the testing they did here is worthless but maybe incomplete. Sometimes there isn't enough time, money parts etc.to do the testing we would like to do so we do the best we can. It is at least entertaining to think that a smaller carb could out perform a larger carb. We as people love a small vs big story and a story that contradicts the conventional wisdom that bigger is better.
It's not surprising that a carb could be either too big or too small depending on what you goal is. Add to this multiple goals like fastest et and good street manners and you open another whole can of worms.