it won't affect your engine performance at all. however your gearing will limit your engine's ability to push your tires around as easily. by going to deeper gears, you take resistance off of the engine by a significant amount. 33s will work, but you probably won't see 5th gear very much unless you do a lot of dowhill or flat land driving.

if you want to run 33s, finding 4.88 gears would be the best(albeit most expensive) way to go, or just run 31s for now

'79 sport 4x4 longbed <img src="/forums/images/graemlins/smile.gif" alt="" />
20/22R hybrid with EB's OS valves, 268c cam, offy intake, weber 32/36, thorley header, 5 speed swap, 34" LTBs, downey 3" springs, marlin hysteer, 4.88s and locked

'91 4x4 shortbed
22R-E, W56, the dd!