A bit of a parts list with the car. It has lowered compression, sleeves as well as pistons and rods. The head was reconditioned with factory oem parts and it is running on HKS FCON. It's a log manifold with a journal bearing Borg Warner turbo running 16 psi and the rotating assembly was tuned to 13,000 rpm and redline was set to 9K. It made 375 whp on a dyno dynamics dyno about 4 years ago and for the past 4 years, it has been driven like it was stolen any chance I got. Ran with a long list of high horse power cars so it has had a fairly fun run. Only driven in the summer so not 4 full years but still, driven a lot during that time.

Fast forward to the present. Had a run with a car on the road as before but pushed it a bit faster this time (higher top speed) not by much I would say though and everything seemed fine until I pulled off at the next off ramp and came to a light, only to see smoke lightly coming out of the hood vent. At this point, no stalls or hesitations; the car seemed to run fine.

I got to my destination, stopped the car and popped the hood. Found engine oil sprayed on the charger pipes and some smoking off if the bottom of the valve cover close to the firewall and battery. I checked under the car and only a few spots of oil. Checked the dipstick and still had plenty of oil in it so I started the car and drove into the garage and let it sit.

The next morning, took another look to see where the oil came from but it was dark and I couldn't get under the car but the oil feed and drain looked fine. Turbo seemed good. Oil pan was alright and still plenty of oil. I started it back up and no oil leaks or spraying so I'm guessing it might only spray at high pressure. I backed my car out to the street to have it towed to the shop who did the install and am now just waiting.

So my question is, what could be the cause of this oil leak/spray? I'm wondering if it could be the valve cover gasket or some other gasket.