ok here goes.
My bone stock LO3 (except for open element and removed smog pump) for some reason starts pinging heavily on one of the back two cylinders when it gets warmed up (175-210 degrees in town). It's done this since I've owned it. I checked the timing, retarded the timing, checked my egr, checked my knock sensor, it still counts the knocks and retards the timing. I've changed fuels, fuel filter...blah blah blah. Any ideas? It carries 50 LBS of oil pressure cold, 30- 35 warm. Oh yeah cap, rotoe, plugs, wires have all been changed. It's kind of frustrating listening to you 44,000 mile old car's engine self immolate it's self off of stop lights. It for the better part quits when theres no load on the engine, like after stop lights, highway speeds, cruising. UGH could it be my cam? I need suggestions.

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91 RS with an auto TBI 305. Metallic Maui Blue, Iroc nose and hood 40,000 on the ticker. No engine mods as of yet. I want a turbo....bad.

 

Could be a valve or something mighth have happened to a lob on the cam. I would take the valve covers off first and inspect the valves and springs, even when it's running. Inspecting the cam of course would require pulling it.

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88 firebird formula
350 Vortec TBI
214int/224exh, .471int/.491exh
Edelbrock headers
SIX-speed
Eats LS1's with a 2.73 open rear and 2 1/4 stock catback

My Formula

 

I would hate to bring up a 7 year old thread, but my car has the same problems. It has an open element and no smog pump. It runs fine when I first start it up and doesn't knock; but when I drive it around the block and come back and it is knocking when I come back. The knock isn't awful but it is noticeable to me. It is more like a deep tick that comes from the top of the engine. You can put your hand on top of the plenum and feel the clinging.

 

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