[yellowman]

I have an Evolution Engines 58 GX. I have read many posts good and bad.
Just for the record, I was unsure at first but now,..WOW what power and starts and runs perfect with lots of RPM!!
First off, make sure that the choke linkage closes the choke butterfly ALL the way. I had to play with mine to get the butterfly centered and to close all the way. Once you get that, it starts every time..three four flips with the choke on and then within three more.
Next,..take the exhaust and cut off the rolled in ends on the outlets. This is causing too much back pressure to let the engine breath. The carb settings I believe that each one might be different but my high speed was a little less than 1 and 1/4 turn and the low speed at 1 and 1/2 turn.
Before I did this the engine lacked power and RPM. I went to a 23-8 prop and it was better. Then after the changes I was SHOCKED!!! 6950 RPM with the 23-8 and 6200 with the 24-10 prop!!
There is NO hesitation between low and high and the throttle response is great!! No more sputtering and hesitation!!
I am still tuning and I will keep you posted.
Also I trimmed the gasket for the exhaust to the same size as the opening in the engine.
I will be flying it soon and I will let you know the difference!!

Al