Hey Guys, First off I read all the threads on this site regarding oil recommendations for users that posted regarding the SR20DET and DE. My engine is pretty heavily modified and dynoed at around 350 whp, with a Tomei Turbo. Long story short, living in southern PA, this car will be driven year round starting in spring, temperatures range in winter to -5F in the worst winter conditions to 95-100 in the hottest summer locations. In the past users recommended M1 0w40, most of the Nissan\SR20 forums recommend 15w50, I can get my hands on Delvac 1 ESP 5w40 and currently am using that. Drain intervals of 5,000 miles (Shorter on track events). Would appreciate any thoughts should I keep with the Delvac 1 ESP or move to something else?