Can't find misfire

nm9stheham said
If the head is still on, retest compression in #6 dry, then put about a teaspoonful of oil in #6 and retest and see if the compression level comes up. That may tell you something about the ring condition in that cylinder; if the compression rings are worn, the compression should go up with the oil added.

You should reuse the later head; the casting is better; you can read up on that in the 'Articles' on www.slantsix.org. You can find the proper procedure for manifold tightening in another article there.

Well, sure enough, I did that and #6 went from 90 to matching the other five at 120. So, it's rings. Kinda as a "just to see what happens", I added a bottle of the engine restore "six cylinder formula." I've also been soaking the top end in Marvel Mystery oil every night after it cools off and I can touch it without burning myself. I'm doing this because I don't see a set of rings wearing that bad on only one cylinder. It makes more sense that they are stuck to the piston. I've been doing the Marvel and driving with the engine restore in it for about three days now, and although I haven't had time to do a compression check, my misfire is almost undetectable. It is running much smoother and stronger. The new valves came in and I went ahead and ordered a set of cam bearings because the other engine needs them. I went to a local machine shop and to do everything I want, he said $671. That is to fully refurbish the head with my valves, clean the block, bore it 30 over, hone it, polish the crank, install the cam bearings, and I think something else. Right now, since it's still in the back of my truck, I haven't removed the crank so I don't know if it just needs polished or if it needs to be ground. I'm also debating on boring it. I think it'll come back with just honing it, but I'd like to try and make a little bit of power, but I may end up saving myself that extra $145 on boring it out and just go stock on it.