overheating slut!!

[trybal]

Blah, ive tried searching with not luck

-sr redtop
-sr radiator
-stock sidemount without proper circulation but wheel liner removed

Just got my car back from the shop, had a cometic hg and arp's installed..

car started overheating on the drive home from shop on the freeway, so i rebled the radiator and all was fine. I didn't drive it much though.

Well now on the freeway it will be fine for 15-20 minutes of driving.. then it will start to rise in temp and won't stop untill i crank the heat. then it goes back to medium. Heat blows hot so i don't think its an airbubble problem. I tried to rebleed and no air comes outta the bleed hole..

I tried to change the mech fan out for a e-fan and no luck. Also, yesterday after the car got hot and i cranked the heat to drop it. I let the car idle for 15-20 minutes with the heat off and it didn't get above 1/2. Untill a few minutes after i started driving it again..

any ideas?

-i bled the rad a few times
-tried new fans
-overflow tank is full like i left it
-does not boil
-feels really hot under the hood
-tried different cap
-not losing coolant


-thermostat maybe?
-clogged radiator?