i just had a quick question to see if s4 and s5 actuators are interchangable? reason is i just recently noticed that i have s5 actuators on and my motor is an s4...pros??? cons??? should they be switched back to s4?

 

S4 aux actuators are controlled by exhaust pressure.

S5 5/6th actuators are controlled by the air pump

I assume you have a s4, since you asked if they should be switched back. The real question is, is your 5/6th aux ports even functioning. Is there an air pump for them to work. Are you running a S5 intake manifold with a s4 motor?

You can switch them back if you like, but you need to run a pipe from the exhaust to open the 5/6th actuators. If you switch back to s4.