I'm looking for some advice. I inherited this car from my dad. In the last few years he was tinkering with it he did some damage. He put a brake booster on it that was so wrong for the car that it had no brakes. I already replaced that. He went so long without changing the oil that I had to replace the block. The whole bottom half of the old block was solid sludge. Cheaper to put a reman on it than to rebuild what was there. Now I'm having problems. As best I can tell it has way too much air coming in. My dad had installed a rich/lean sensor which reads extremely lean and the exhaust smells lean to me. The timing is off just so it will run at all. I fixed the spark plug gap which was way off on most of the plugs. I guess the mechanic that switched the block didn't check that himself. I checked all the vacuum lines with carb cleaner and replaced one that was sucking air. The egr valve is off and properly blocked off which gave me a slight improvement. I cleaned out and rebuilt the quadrajet carburetor (yeah, I know). It improved somewhat but now the rpms surge at random, mostly when cold. Rpms are way high when it's warmed up. Still can't drive it. Messing with the timing doesn't improve anything. Plug wires are triple checked as of yesterday. I suspect that the intake manifold is incorrect for the vehicle. It has a pretty decent rise on it which the stock one does not have. The heads have also been replaced with aluminum ones. I don't know if they are correct for the car. I have the original heads. I found a hairline crack in the base of the carburetor. I packed it with silicone as a temporary measure. So, I have a few options of where the problem might be. Switch out the intake manifold for the correct one I got off of someone else with a Chevy 350. Replace the carburetor with a new one with matching specs, probably an Edelbrock. Switch out the heads for the original ones assuming they bench test ok. What would you do first?
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