What kind of oil is better for a 99 gs with AEM cool air and no other engine mods. I figure it is still early enough to swich it over since it only has 46,000 mi. Is synthetic better or should I stick with the regular cheap stuff. What do you run in your cars?

castrol gtx

I also use castrol GTX good stuff...

thanks I'll try that

i use Castrol (might be GTX) Drive Hard... works good, lot better than that halvoline shit

I use Mobile 1, seems to work great. Oil looks alot better at every oil change also.

Kyle

if use synthetic oil, which is better, Mobil1 and Castrol?

it's expensive but if you really want some good oil
try finding some Redline Oil..