i have a 84z28 camrao and the guy before me had droped a 350 in the car. but he doesn't know what year it is. it has the 4 belts on it instead of a serpentine and i was wondering what could i possible do to make about 300-400 hp out of it cheaply.. thanx ohh and it's carbed

 

Sounds like the stock '84 belt set-up.

Really need to know more about the engine. Best way to start is to pull a valve cover and get the casting number off of the head. A lot of 350 heads were performance dogs, so no matter what else you do to the engine, the heads will hold it back.

While you're at it, try to get the casting number off of the block, which is located behind the driver's side head (hard to see). It's easier to see with the valve cover off, so take off that side to get the head casting number (although it might not be a bad idea to get both head casting numbers, as mixing/mismatching is a common problem).

As for performance in general, an '84 Z28 could have had either an LG4 or L69 V8. The latter would be a good thing, because it was equiped with what it takes to support a 350. If LG4 originally, it isn't the end of the world. But, figure on exhaust upgrades (headers, cat, & cat-back for '86-'90 TPI single cat application is a good plan), cam, and if LG4, you really need to upgrade the air cleaner to the L69-type dual snorkel (or fabricate one - see tech articles on this board). The heads may need some porting work, upgrade valve springs, or just plain replacement if they're '70-era smog pieces (unfortunately, that's more likely than not). The carb is more than capable of the HP range you're looking for, so resist the temptation to replace it.