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A previous thread raises an interesting question: Would it be better to control the compression ratio by using thicker cylinder to crankcase gaskets, or by milling out some material from the cylinder head combustion chamber?

I happen to have a T-IV engine with .123 inch deck height and 53 cc heads, giving an 8.5 : 1 compression. No gasket at cylinder head, only gasket(s) at the crankcase. I did not build the engine, but some folks seem to think .123 is a bit "tall". I'd have to agree, but the engine runs fine with good power. Will this end up being a long term sealing issue?

Anyone with experience? I know someone will have an opinion! Thanks.
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A previous thread raises an interesting question: Would it be better to control the compression ratio by using thicker cylinder to crankcase gaskets, or by milling out some material from the cylinder head combustion chamber?

I happen to have a T-IV engine with .123 inch deck height and 53 cc heads, giving an 8.5 : 1 compression. No gasket at cylinder head, only gasket(s) at the crankcase. I did not build the engine, but some folks seem to think .123 is a bit "tall". I'd have to agree, but the engine runs fine with good power. Will this end up being a long term sealing issue?

Anyone with experience? I know someone will have an opinion! Thanks.
I also found out that not only are there spacers that fit between the cylinders and case but Bugpack offers copper shims that fit between the head and top of the cylinder to do the same thing. According to my very reliable sources, those copper shims work great as you don't have to remove the cylinders and they seal great too.
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