I have a 1990 LO3 bone stock besides the ultimate TBI mods. Is it worth it to put in a bigger camshaft? If so how much duration/lift/separation should I look for? Maybe a particular model. Around how much power would I gain? What else would I need to do this mod? Lifters or springs? Thanks for your advice

 

Hey welcome to the boards. A cam swap is alwyas a nice mod to these cars because of how weak the stock one is. However there are many other factors that you must consider. You really should start with a full 3" exhaust, upgrade your fuel system and familiarize yourself with chip burning. You will need all of those with a cam swap. There are countless set ups to go with and I suggest you look around in the TBI board and check out some posts that ask the same questions. You will find great info and it will keep you occupied for a couple days. Also, the search function on the top right of your page is a great way to find specific answers to some of the basic querstions that new people have that get covered everyday. Good luck and happy modding.

 

Much like Shifty said, a search will yield much info. Here is my opinion:
Before you do a cam swap, definetely think about other mods to do before hand and in conjuntion with it. Mods to do before hand would be full exhaust, open element or other than stock air cleaner, and ignition mods to help you pull the higher rpms the cam will give you. Gears and posi are also a good idea, depending on what cam you go with, you'll most likely be looking at 3.42s or 3.73s. Also, a higher stall will work much better than the stock one, you would need to match it to cam.
Mods to do during the swap would be intake manifold, springs, and lifters(if your engine has a lot of miles).
Also, the LT1 cam is a very popular cam to swap into the L03. As far as which year is best, it is debated, and a search will help you find info on it. Best of luck.