Do i need a valve job?

Ok... So I posted a thread earlier asking about the best headers to buy for a 96 z28 camaro because my mechanic said I need a valve job... everyone that responded to my post seems to think that I might not need
a valve job... so let me post this question to everyone. Here is what I already know:
The car has been misfiring terribly on the #3 cylinder. This misfire occurs throught the driving range and is causing my SES light to blink. The fuel lines have been checked and I know I have good fuel pressure. The spark has been checked and I know each cylinder is getting good spark, and there doesn't appear to be a vacuum leak anywhere.
The mechanic who worked on the vehicle told me I needed a valve job. When I asked him how he knew I needed a valve job, he informed me that he had checked cylinder compress on #3 (the misfiring cylinder) and that the cylinders were getting good compression, but that my vacuume was going up and down speradically. He insisted that it meant I needed a valve job. He said that he had not had an opportunity to take off the valve covers but that he was sure that the valves were my problem.
Now, i'm no rocket scientist, but as I understand it, if I needed a valve job, I would not be getting good compression correct? The car is a high milage beast (160,000 miles), but if I have good compression, how could I need a valve job? Today I took off the valve covers and there doesnt appear to be ANY caronization around the rocker arms or valve springs... in fact, I was surprised at how clean things looked. A little bit of dark colored oil was present, but nothing worse than what you would find in your oil pan before an oil change. Shouldn't there be carbonization everywhere if the valves are screwy?
I've listed everything I currently know about the vehicle. There may be some important information I am leaving out, so please feel free to ask questions. Any help I can get would be greatly appreciated. Thanks.
oh.. PS... does anyone know where I can buy one of these exhaust things? I dont know what they are called but here is the url for a pic of it:
www.nathanielmills.com/thing.jpg
any idea what its called and where I would order one?
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I think you are way over-worried about valves. Replace the broken spring, or have a shop do it. It shouldn't be too expensive. Then see how your car runs and have some fun.
Oil carbonization is not related to valve performance, per se. It is related to overheating and failure to change oil regularly. If you see no evidence of carbonization, consider yourself luck that the previous owner(s) changed oil regularly and didn't overheat the engine.
Your "exhaust thingy" looks like an A.I.R. pump check valve. Get one at your Chevrolet dealer's parts counter. What makes you think you need a new one?
wrote:

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Replace what spring? I did not read anything about a broken spring in the OP.
I might suspect a bad fuel injecter, try some FI cleaner first, or switch #3 inj with another one and see if your miss follows the injector to the new cylinder.
Correct on the check valve.
On Thu, 14 Sep 2006 01:13:57 -0600, John Ireland

Randy
Remove 333 from email address to reply.
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In an earlier post he stated he took off the valve cover and found a broken valve spring. See "officespace 2 9/12/06.
Sorry about the slow reply. Been away.
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On Thu, 14 Sep 2006 01:13:57 -0600, John Ireland

I think he wants new heads and is looking for an excuse to get them. Dude, if you have the money, GO FOR IT!

-- lab~rat >:-) Do you want polite or do you want sincere?
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