Raising compression?

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EvhCo

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RC Driving Style
  1. Racing
I always thought there has to be a way to re-raise the compression of the piston/sleeve, understanding the physical properties of steel (which I don't too much), and a classmate of mine said that the engine might (just might) regain the compression potentially lost in a day's work by letting it overnight in a cool, or even cold place (such as in the yard on a table), to counter the combustion's effects on the metal. Do you agree with this? Are there other ways to raise or otherwise prevent compression loss (apart from pinching)?
 
Loss of compression is due to piston cylinder wear. Because these small engines typically do not use rings for compression there is not much you can do other than replace them.
 
Repinching is an option as well. Also, by removing a head shim, you increase the compression. There are reasons for and against removing that shim however. If your compression loss is from regular use and wear, removing the shim is not the way to go.
 
Compression is still as new on mine, just looking for preventive measures. Thanks for the tip :)
 
Raising and lowering compression with head shims is mainly used for different types of fuel percentages. It may be used for racing 'cheats' or similar as well but I am not familiar with that type of adjusting or what it would do to long term engine life so I recommend a lot of research prior to changing shims to reach you ultimate goal. Def post about your findings tho. I am very curious to know what you find.
 
Raising and lowering compression with head shims is mainly used for different types of fuel percentages. It may be used for racing 'cheats' or similar as well but I am not familiar with that type of adjusting or what it would do to long term engine life so I recommend a lot of research prior to changing shims to reach you ultimate goal. Def post about your findings tho. I am very curious to know what you find.

The head shim "upgrade" (if it can be called that) seems a bit overkill, especially when pistons and sleeves are so easily available (and even cheap), assuming you know which one's good for you. But as I glance at certain pictures of dismantled cooling heads, all I can imagine is that the piston hits harder on the cooling head's bottom without the shims, and that definitely doesn't do any good in terms of saving an engine from wear. Although my gut tells me there should be a way that the shim's actual material might improve compression. Will be an interesting study.
 
There should be NO contact with the head and the piston but the gap between the 2 is lowered, increasing compression.
 
Oh, I thought they would actually contact by the looks of it. This might also increase temperature, which is already high on mine (not a problem since I run in a cold climate). Once I get a new set of pistons'n'sleeves for backup, I'll get to it.
 
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