Uni Syn works great for equalizing air flow using the built in manometer. However, and a big "however" is the old ones from back in the day, (70's) are terrific. However later on there was a China knockoff one that looked exactly like the real one (still said "Uni-Syn" in big letters)but would not work at all. To get a reading it choked off the airflow enough to screw up what you were trying to do.There was a guy that took one of the cheap ones apart and measured everything and it was all just like the real one but just would not work. Never did figure out why but it did not work and choked off the airflow that it was trying to measure. Uni-syn got a bad reputation from the junk ones. If you have a really old one, use it. If it looks like a real one but has lettering on it saying "China" throw it away so no one else can try to use it The one shown above says :Taiwan". so I do not know how well it works. I have used my original Uni-Syn on many Porsches and they work great. Twin carbs 6 barrel carbs and 6 stack fuel injection systems etc Just get a real one. I have no problem with made in China in general , but junk is junk wherever it is made.
