Hi all, This is my first post here, and it is with regards to my 2004 Honda S2000. First a little background on what brings me here. The car has ~31,000 miles on it, and sees lots of autocross action, as well as daily driving. Ambient air temperatures at an autocross can often approach 100*F on a hot day. The engine's fuel cut occurs at just over 8,000RPM, and the car spends most of track time above 6000RPM. The owners manual specifies 10W30, with a provision for 5W40, if the car is driven in temperatures under 0*F. Previously I had been running Mobil 1 10W30, but I had a UOA done awhile ago which stated that the oil was performing like a 5W30. The OCI was 3000 miles. I'd also like to move away from Mobil 1 as it has a reputation for killing timing chain tensioners in Honda S2000s (although I have no idea why, it just seems to be a common component in many TCT failures) I'm looking for a recommendation for a good synthetic alternative that will hold up to extreme temeratures and revs, and still be suitable for daily driving, while not breaking the bank. Also, how much stock should I put in Honda's call for a 10W30 over a 5W40? I've thought about switching to Shell Rotella T 5W40 or Motul 5W40, but I'm unsure if this is an appropriate weight for my purposes. I have also considered RedLine 10W30. Any ideas, comments? Thanks.