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Old 07-07-2012, 01:28 PM
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Did a little more work on the valve stem seals today. I went back to cylinder #2 and used pliers to remove the seals from the intake and exhaust valves. Gonna head out to Autozone and see what they've got.

Originally Posted by cobalt327 View Post
I don't have a part number, but the seals will be the same as those used on a 1987 Camaro 305 w/TPI, for example. Some sources cite the GM factory positive seals as fitting a 0.561" SBC guide boss. Measure the guide boss OD to compare, most aftermarket type positive seals have a smaller OD (=/< 0.0530") to allow an aftermarket/double spring to fit over them. You should be able to find the seals at any parts store, just inspect them first for having similar dimensions as the ones you have.
I probably should've asked about the boss guide sooner, but I think I measured the correct part (circled below) and the diameter came out to be just about 0.561".

Also, I am considering doing a basic cam swap at this time as well. I want to learn how to do it and also get a bit more smog-legal oomph out of this engine. I asked for recommendations here: Chevy K20: Camshaft Recommendations for a Crate 350. All input welcome and greatly appreciated.

Will report back shortly on the seals.
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