Hello,
Just wondering what the side effects are of free porting?
I have a home built 30.5, and i know it has 5 degres of freeport. I have been having alot of trouble getting it to run well.. It will rev out if i open the throttle slowly, but if i am quarter throttle and then go wide open it stalls? i havbe played quite a bit with the mixture, i can make it worse, but no luck making it better. No Load it is fine...
Carb is a 1048

You could have a carb issue, so try a different carb since some of the WT-1048 carbs can be finicky to tune or won't tune at all correctly and if you rebuilt your carb make sure the gaskets / diaphragms' are in the right sequence. Check the engine over and make sure all parts are secured.
Exhaust free porting if excessive will cause loss of power due to the intake draw will cease due to a leak and some of the fresh charge sneaks out when the piston descends, You can add a .020" gasket to eliminate the 5° Freeport., doing so will also increase exhaust duration by 5° and lower intake duration by 5°. and increase your squish by .020"...the only other option is get a new cylinder.

5 degrees of freeporting at the RPM we run these motors is small, and won't be the cause of your problem. Now if the exh. port has been widened too far and the piston skirt has a large amount of "M" cut, it could be freeporting at the sides of the skirt as well as at the bottom of the skirt. THAT could be a problem. Small amounts of freeporting have shown to help performance in SOME cases.

For your problem I would look at air leaks and carb issues.