OK, I am now the proud owner of two thirdgeneration IROC camaros. The first one is a white 1990 73K with the 5.7 which I purchased 3 months ago: I love it, this thing is great! I did all the basic things: KN airfilters, total fluid changes, 2 sets of plugs( the first were rapidfire platinum and second were the stock ac delco) new msd coil, 8.5 msd wire set( built it myself which was quite a feat for a mechanically challenged person like myself), crappy accel cap and rotor( well let me explain: basically the terminals were too short for the msd boots so I had to cut my newly built boots down to fit it) which I will soon be replacing with the MSD cap and new boots as well. I started checking this site for info on maintenance and it is full of knowledge: infact I have yet to have a problem that this site has not answered right down to the gob of glue on the msd coil that interferred with the bracket installation( I also had to file the bracket to make the coil fit properly ). Anyway my questions are many but I will try to make them clear as possible.

First of all I use about 1 qt of oil in 1000 miles with no smoke that I can see either at start up or at wot. I am guessing it is the famous valve seals as indicated by the #6 plug that was partially gap bridged (with carbon and soot but not oily or oil fouled )when I changed from the plugs that were in the car when I bought it to the rapidfire platinum plugs they lasted about 800 miles then the car started cutting out above idle. I pulled them and again the #6 plug was completely gap bridged and the # 8 was partially bridged. This was when I went to the AC Delco factory plugs and changed the ignition stuff as mentioned above: this seemed to have solved my problem as I have driven 1500 plus with no probs.
There were no oil leaks on the seals until I converted to Mobil 1 10-30 and then they started to seep sligthly at the valve covers and oil pan gasket area. So I checked with the GM dealership and the valve seal replacement was quoted as 425.00 and at my local mechanic shop it was 250.00. I am leaning towards the GM dealership at this point( I would attempt this at home but all I have for working area are a gravel driveway and car port with no air compressor to hold the valves). Should I get this done as soon as possible or can I wait a while? One other thing I forgot to mention is that oil will occasionally leak out of the oil cap. Is this also caused by the valve seal leak or something else in the vac system ?
Ok, so now for the rest of the questions:
I loved the 1990 IROC so much I found another one at a local towing yard( a red 1987 IROC (128K) with the 305 / 5 speed ) it had no radio or wheels but the rest was straight and clean. I bought this one ( told the wife it would make a great parts car when she questioned my sanity ) thinking that it would make a great parts or project car. So, it said bad motor on the documentation and after getting it home and checked out this weekend ( I pulled the ignition cylinder and had a key made ) it started after a few cranks and backfired and it ran and has a knocking noise on the passenger side of the engine on top.
I figured it is probably a spun rod/crank bearing or broken connecting rod but here is the strange thing as it has 40lbs+ oil pressure on the gauge and goes up when I increase the throttle.
Could this knocking noise be something else as it also does not knock constantly but intermittant and it comes and goes. Could it be a valve issue? It is fairly loud at times but goes away at times.
I have not run the motor enough to warm it up as I wanted to determine the problem only and work on a fix. Is the 305 worth rebuilding or replacing as I am not really concerned about the horsepower issue ( I have seen that many recommend the 5.7 swap but I am not really that interested in changing the motor and tranny unless it will be cheaper )as I wanted to make it a daily driver for a cheap as possible. Any ideas or information would greatly appreciated.
Thanks too all of you for all the great information on this site.

 

Negation,

You may have valve seal problems. Does the engine smoke on startup, then stop within a few seconds? That would be an indication of valve stem seal leakeage, but that typically isn't enough to foul or bridge spark plug gaps.

Your oil seepage from the filler cap indicates a crankcase pressure problem. Check the PCV system, both the valve and the crankcase breather tube. An inoperative PCV system can allow excessive crankcase pressure and force oil out any openings, like the filler cap, gaskets, etc. (sound familiar?)

If you decide to change the valve stem seals yourself, you don't necessarily need an air compressor to hold the valves in the closed position. You can feed a length of soft braided nylon rope into a cylinder through a spark plug hole (keeping the end available, of course). Once the cylinder has a couple of feet of rope in it, rotate the engine by hand via the crank balancer bolt or other suitable means (NOT the starter) and the rope will be compressed against the valve faces. This method was used long before the air pressure method was devised, and has apparently been forgotten. However, the lack of a puff of smoke on startup may mean your seals are O.K. and don't need replacement.

The fouling of the plugs could also be related to the PCV or excessive crankcase pressure. If the situation persists despite your service of the PCV system, you might want to consider moving to the next hotter heat range spark plug to deter the formation of deposits.

 

As for the '87, a piston pin slap, rod or main bearing noise usually doesn't vary, unless it makes noise immediately on startup then disappears with oil pressure increase. It's more likely that the noise is in the valve train, especially if you are hearing it at the top and only on one side of the engine. This can be a good thing compared to a bearing or pin, since it is a lot easier to repair in the car than a bearing problem. A broken rod bolt or cracked rod would be a lot more apparent and wouldn't "come and go" as you describe.

It would be fairly easy to remove the right rocker cover and check out the valve train on that side. Don't overlook the possibility of a sticking valve, and check for bent rockers, loose rocker studs, bent pushrods, broken valve springs, etc.

Good luck, and let us know how it goes. Maybe your wife just inherited a second car for a few bucks in repairs...

 

Thanks for the quick response Vader,( first off I have not noticed any smoke on start up or when wot but I may just be missing it ) on the 1990 model I replaced the pvc valve when I did the fluids( I used a fram one).
Shortly afterwards was when I noticed the oil coming from the filler cap. I changed it again and used a AC delco one which seemed to lessen the problem but not totaly eliminate it. The strange thing is that I have a daily commute of 60 miles to work and I would wipe it off and it might not appear for a day or two.
One thing I failed to mention is that when changing the plug wires I noticed a vac line on the passenger side of the TPI unit
that goes into the TPI unit had a hole in it( about the size of 3mm to 4mm ). It was badly decayed and was crumbly as well when I removed it. It ran to a T fitting that went back under the TPI unit and to a cylinder shaped object( I tried to find an example in the Haynes and Chilton books but all it showed was one on the driver side )which looks like the vacuum damper valve. Is it possible that a chunk of the hose was sucked in and is partially blocking the system? I checked the books on the rope method it looks fairly easy but I am really concerned about doing the valve seals outside in a dusty/windy carport coupled with my limited mechanical experience to this point.
As for the 87 IROC ( the wife likes it more than the 1990 as it is red with T-tops and a 5 speed vs white automatic with a pink stripe so I may be in luck if I can get it run ). On the several times I started and ran it the noise would not appear at first on some starts and then after it ran a few seconds it would begin then go for a few seconds and cut out but on other starts after a few seconds of running it would come and go( run on sentence excuse me). I will pull the passenger side rocker cover this weekend and take a look.
I will give an update on what I find.

Thanks for all the suggestions and help.