Penrite engine oil is absolutely S**T!!! I used to run it, then went nulon which was way better and now liqui moly which is better again, in fact so good that my motor leaks from places that i never even knew existed!! LOL! :D Another important thing is to change your gear box oil. IMO its more important than having fresh engine oil when youre racing, gearbox oil will make it so that your box will change smoother, and reduce crunching. I change my gearbox oil before and after I track the car. If its daily use i change it every 20,000. I use 75-90 Western Oil Syngear with a heat resistance additive, the name escapes me which one it is... Engine oil i change every 4,000 (4AGE's tend to turn their oil black pretty quickly) As Ben said, brake fluid and pads are also a critical thing to maintain! Penrite racing fluid and QFM A1RM pads work best IMO :)