340 Static Compression Numbers and Test Procedure

340inabbody said

Don't have any close ups of the Plugs. Plugs are relatively new so may not be a great indicator of much. But it looks like most everyone agrees looks like detonation marks. If I correct the detonation is there any issues running the pistons as is? Clearly if I yank the motor I would replace the pistons. Was wondering if I could shim the heads to lower the compression which would be the easiest way but not sure if that would be enough to lower the count by 2 which maybe whats needed...... I have to find someone with a Whistler here in Phoenix.

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If it didn't lift the ring lands you can still use the Pistons. They are pretty tough.

If you are going to pull the engine down, CC the heads and then measure how far the deck is either positive or negative relative to the block.

Then you need to figure out what cam you have.

Then you can start making informed decisions about what to do next.

You can mill the dome off of those Pistons. I've done it, many times. I use that piston in the engine in my car now. And I'm at 11:1 with it. And no issues. But I had a PLAN to do that before I started.

I'm not a guy who will lose my marbles if I don't have a quench distance of .035, but I also don't want a dome bigger than I need. That's why my piston is out of the bore .045 so I can get the CR I wanted with a dome that is about .187 high.