How clean is 'clean enough' and is this something I need to do on a regular basis. Also, does a 'not perfect' manifold degrade performance or is it more of a passage open/passage blocked type of item.
I took the upper portion off and looked inside, it'd a little dirty with carbon and gas/oil or whatever the gunk is. The passages seem a little coked up but not too bad. As long as I am this deep into it I will take the lower off and finish the job but wondering is this a necessary maintenance item.
How often do you all clean yours and what's your technique?
Thanks for the replies.
Bruce