Plenum head

[timshap]

I have just removed the head section to find the trumpets quite dirty inside with deposits and oily at the base etc.. should there normally be such a build up towards the back nearest the stepper motor outlet? it was fairly sooty.
Having cleaned out the whole thing the car/engine felt much smoother and felt as if it pulled better..
Should the trumpets and inlet manifold be cleaned regulary it isnt a service job though!!!
Views all please..

[2 Sheds]

Firstly This is normal especially with a hotter cam, it is called reversion, off cam the engine pulses run in both directions, ie sucking and blowing so that exhaust fumes will enter the plenum,
You can clean this easily but i wouldn't recommend that everybody dismantles their plenums , as it shouldn't make much difference unless very bad.
Tim

>> Edited by 2 Sheds on Wednesday 24th July 20:58