ive been seeing dropping oil pressure for the last couple of months on the cossie, i changed the oil to try and resolve it and put in silkoleane pro s but the oil pressure dropped further. it runs 45-50 psi when cold but drops to 15 psi on idle and 25 - 30 when running now.

I drove to our local meet last night and on the way i noticed vapor from the bonnet vent and shortly after i had a top end knocking so pulled over. opened the bonnet and vapor was coming out the spec R breather filter and a nasty tappet knock from the back of the engine, i opened the oil filer and the knocking stopped a little but shut it down. checked the oil level and it was half way up the dip stick.

The car has also been running hotter and when on idle the fans strugle to cool the engine and ive noticed the powdercoat on the rocker is blistering on the inlet side..

If the oil pump fails does it drop pressure like this or would it just die? I have a horrid feeling my engine is now in need of a rebuild I have a freind coming round next week to do a compression and leak down test but what do you guys think it sounds like?

I also have had an issue where i have lost power and have a real flat power curve, would the lack of oil pressure prevent the lifters from opening the valves fully hence the poor performance or is that bollox? Advancing the exhaust timing did give me a 30 bhp power increase on the dyno..