A small poof of smoke might not be a big deal.....if it fogs the neighborhood, that's something to worry aboot!
Could be valve guides/seals, sure. One way to check for that is to drive the car on the hiway, then let off the accelerator all the way, and coast down(safely, if in high traffic) until around 30mph or so. Then get back on the accelerator, and look behind you.....if you see a large cloud of smoke, it's the valve guides/seals. If you changed seal before in a small block, it's the same procedure for what you have now. Use the "umbrella" type seals....not the squarish looking ones, or o-rings. Most folks only install seals on the exhaust valves, but I prefer to use them on intake and exhaust. New valve seals will certainly help if you find the problem is that, but if the guides are worn, the new seals are really only a temporary band-aid.
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Joel Adams
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