im off my b20 install so im using regular dino oil right now, but ive always used mobil-1 in my ls. it really doesnt matter, just get the weight right for your climate.

 

i run castrol GTX 10w-30 in my 98 ls with 91,XXX on it. synthetic is not really good for older engines that are not running on it already. it will clean a lot of buildup internally but that may cause oil to leak from different seals. regular oil should be fine, just change every 3-4k. make sure you use a good oil filter - they are not all the same.

 

All of this talk is really better suited for our ITT Maintenance Thread. <link>

In fact it's already been covered there.

 

my friend has a 92 civic hatch dx with 299k on it...and still runs like a champ....lol