well i have put at least a little bit of thought into just about everything that has to do with my car, BUT oil. right now i have a crx w/ 97 d16y8 w/ 60k w/ intake, y8 manifold, headers, exhaust, and a dry zex kit, i'm using my si trans. w/ a l.flywheel and stage 3 clutch. i know what i have done will make some kinda differance so.....
my question is what wieght oil should i be using? my dad says 5w30, but i'm running it with 10w30. am i ok or is there something else or better for me to use?

 

The difference between '5' and '10' only applies to colder temperatures. The '30' is the weight of the oil once the engine is at operating temperatures, so in the summer time, you're splitting hairs. In below freezing temperatures, 5w30 will help with starting and fuel economy while the engine is cold.

 

so is royal purple oil worth it or no?

 

If synthetic oil fits your budget it's always better than a conventional oil protection wise. Just don't expect to notice any power difference, you're just paying for better protection. I only use synthetic in my car.

 

I've stuck with regular oil since I've owned my car. I use 5w in winter and 10w in summer. Like AngryTroll said, the number before the "w" applies to the weight of the oil at cold temperatures. In colder climats, it's better to run with 5w. My helms manual says to use 5w in -10C to 30C and to use 10w in 0C to 30C. As long as you stick with w30 oil you're ok.

If you want better protection for your engine and it's within your budget, go with synthetic.