Before i change the inlet gasket on my 3.5 v8, i thought id run my reasons for doing so by you guys first, just to make sure that my symptoms are what i think they are:

Ok when i blip the throttle under the bonnet, i notice smoke coming out of the breather at the rear of the left bank of cylinders, and also a puff of smoke from around the inlet manifold, if i hold the throttle open it doesnt smoke as much,

Ive had the plenum chamber off and theres a hell of a lot of oil in there. This leads me to think that i need a new inlet manifold gasket as im guessing that under load the gasket is leaking allowing air in and mucking up the oil breathers somehow and drawing oil up into the breathers and then around the inlet etc? I suspect said air leak would also be causing lumpy idle and also causing the car to rev for a few seconds after i come off the throttle at a junction for instance.

Can anyone wth V8 knowledge give me a few pointers!