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Message: <blockquote data-quote="Silver95bird" data-source="post: 1404343" data-attributes="member: 21743">Okay, so let's apply this...I have a few real life application questions on this. Let's say you have a 2v car, and take the heads off to do a P&P job, or even for repairs. Traditionally, we'd look at thinner gaskets and decide the compression change wasn't enough to be worth ordering a special gasket over. Combining not just the compression, but also the squish distance, is it more worth ordering the shortest gasket that will provide a safe (say, .025") margin so the pistons don't kiss the heads? A lot of people won't be decking heads and blocks, but they might pull the heads off for porting or PI headswapping along the way. How much more timing does this reduction allow? The swirl dams often have sharp edges on them, and it's long been thought that those areas are likely among the most detonation-prone areas in the head. Is this squish issue an even bigger issue than that, detonation wise? I'd like to posit the idea that perhaps there's more to gain from this by the fact that reducing the squish area reduces the areas of the block, heads, etc. exposed to the heat near ignition at TDC, making it more efficient by giving the lit charge less area to dissipate the heat into. Ring lands are hugely famous for being failure prone on 4.6Ls, mainly lost to detonation. Assuming the tuner isn't a moron, does this shield the pistons a little more from heat and failure at those edges? I add the caveat, because a bad tune will kill anything if they try hard enough. I'm talking about moving the safe (non-detonating) timing borderline without causing damage versus a comparable engine. Does sticking the piston out of the hole on a 4.6L start to cause issues since the rings are so close to the top? How far is too far?</blockquote>