SR20DET Coolant issue?

When I take my car out and beat on it good the overflow fills to the top and starts to stray out in the motor. So I wait and then I take the radiator cap off and it is low and the coolant in the overflow never goes back into the radiator. I took the head off had it machined because it was warped and the overflow was bubbling, put a new headgasket on and it still does it just doesn't bubble in the overflow anymore. Does anybody think that I could have a bad flowing radiator. I have no thermostat.. I don't see how that could be the problem cause that wouldn't cause the overflow to fill to the top, but I don't know anymore.
I need some info cause this is confusing the hell out of me.
Thanks

Do you have the stock KA rad? If so, get a good rad.

I have a koyo aftermarket rad.

u have air in the rad! fill it up!

wait till its cold, fill it up, turn te motor on (cap off) and keep adinh water till its full, air will bubl out, water in, and ur cool.

What's a good water/coolant ratio?

50/50, if you can get away with it, run less coolant, until winter time anyways. Supposedly, the less antifreeze, the better it cools. But can I get someone to back me up?

Well I don't drive mine in the winter. On the back of the Redline Water Wetter bottle it says to not go less then 15% coolant on a street car, does that mean that the less coolant, the better, but it's not a good idea to go to low when street driven?

SR's tend to overheat easy when you beat on them. Best to replace the points of failure. New rad cap, new water pump, new thermo. Also make sure you're getting enough airflow especially if you have a front mount IC. ie: electric fans working properly?

50/50.... more ANTI FREEZ when temp gosez down.

water what keeps the motor cool, antifreez (Mono Ethylene Glycol) drops the freezing point of water and prevents rust.

you just don't want it to run as cold as possible the entire time....

Yes. Finally someone else sees this. Oil has to reach a certian temp to acheve proper viscosity. Hence why you don't race a cold engine. It can also effect engine clearances by causing them to remain too large. This will cause rapid engine wear. I don't see anything wrong with running a stock thermostat, a good radiator, and a decent fan setup with proper coolant/water ratio of 50/50
Install a thermostat...

The reason I took the thermostat out was becaue it was being blocked my my water temp sensor...but I'll just have to move the temp sensor so I can put the thermostat in.
Thanks I let you know what happens