Hows it going olds family . Im putting a olds 455 with stock intake in my cutlass can i use the heater control valve off the 307 i took out of the car .

 

Ok, I think you said the heater control valve is stock to the car, and you'd like it to stay. The difficulty is some take vacuum to open and some to close, but, if it's the one for the car, then it will control right. If it will physically fit, like same thread into the block (it should be) and it lines up with your connections (that I don't know), it should fit and work. What condition is it in? While you're there, it might be worth replacing if it is crappy.

 

The early engines used a different size thread than the later engines. I think the early ones were smaller, so if your intake has the smaller hole it may not be possible to use the original 307 larger thread heater valve. It should be obvious if it will fit. Going the other way is simple, just use a reducer bushing.

 

Thanks the thread issue was what i was wondering about

 

Other makes used an inline heater valve, so it is possible to use a restricted nipple on the intake manifold and a vacuum controlled inline heater valve. You just need to find one with the appropriate vacuum control (vacuum opens or vacuum closes).