If the 160 lost some performance or the engine just wasn’t happy, that’s a good sign that the fuel wasn’t being atomized enough coming out of the booster. When that happens you get too much liquid fuel in the chamber. That’s why it was happier at 180. That extra heat helps vaporize the fuel more so less liquid fuel enters the chamber.
Of course you can over atomize the fuel out of the booster. If that happens with too much heat in the engine the fuel will vaporize too much and it takes up an incredible amount of area in the ports. Then you lose power.
Atomization and vaporization go hand in hand. You need both without too much of either.
And then there is the bugaboo of the distillation curve, which can be near impossible to find on pump gas. You can get it for race fuels pretty easy.
If the fuel has a lot of light ends in it, you have to be careful that you don’t over atomize the fuel out of the booster Andover heat it once it gets into the plenum.
If the fuel has less light ends in it, then you need to atomize it more and maybe even raise the engine temp some to get it happy.
It’s tricky when you really start looking into it, and pump gas is very difficult to get a handle on because it’s like the wild, Wild West. You can have the same octane rating (which doesn’t mean much but I digress), the same amount of ethanol and have wildly different distillation curves. It can drive you crazy.
