I purchased a really, really clean, all stock 2001 ECSB 5.3 for a steal of a price. Only down side is that it has 66k miles on it. I am planning lots of bolt-ons along with cam, timing chain, oil pump, pushrods and valve springs. I am trying to avoid removing the heads. Do ya'll think the stock heads with 66k on them are fine or will they kill a lot of my anticipated tq/hp gains? Thanks

 

If you go to a higher lift cam, you will need to go to stiffer than stock springs like the Comp 915 or 918 springs on your Camero SS. When you replace the springs, replace the valve seals. Be careful not to scratch the valve stems and your home free. Compared to dropping a valve keeper or the spring flying off, installing valve seals will be easy. You do not have to pull the head. Just use compressed air to hold up the valves (which you need to do anyway when changing the springs).