Ok, I have a 00 GSR, it's seen a couple track events, but I've been doing this for a while and I haven't had any problems, the car feels great. The only thing I notice is that about every oil change, it's short maybe a .5 to 1 full quart or maybe a little more. Any idea? I use Castrol Syntec 5W 50 and it only has about 93k on it. It doesn't smoke or anything. The engine bay is clean, as is the underside of the car. NOTHING is leaking. Please give me some opinions.

I have not done compression or leakdown yet. I'd like to explore other options before I do that.