So my 1986 Camaro is the v6 without A/C, I replaced the heater core and got my blend door unstuck so that I don't just have defrost. My cool air blows super strong like it should, when I switch the control to hot it works really good on defrost, but on vents it blows weak warm air out of the floor vents and weak air that's cool out of the top 2 dash vents. Please help, I'm cold.

 

No clue on any of that, mice are bad round here so I gut heat & a/c on most my projects. Still if things don't go well https://www.summitracing.com/parts/rpe-3501/overview

GL!

 

You still have a door problem... There are multiple doors... At least three three is I remember....

​​​​​​NEed to check all door operations... Sounds like one is stuck... Get a good HVAC diagram for your car..

 

Multiple doors. A blend door to allow heat into the HVAC system. Damper doors to change the flow of air between defrost, middle and lower dash. If you feel heat from one of the other outlets and not another then one of the damper doors is not working, duct leakage etc.