|
Was able to get everything today to calculate my CR. Comes out to 10.42/1 roughly. To get my chamber volume I used water with dish soap (to reduce surface tension), put spark plug in, then put a flat and clear film over the chamber. I then put a small hole in the film so that I could add the water. This ensures the water is level and also reduces the circumference at which the water will want to try and raise above the surface of the film. Can't remember the names from chemistry or whatever but hopefully you get what I'm trying to say. After carefully measuring I was able to get the same numbers back to back so I called it good enough. Also looks like I'll need a single indexing washer for the plug to ensure it's facing the right way. Seems as I can only get the washers in a package for about $14 I think I will spend the $20 and just get a Brisk 360 degree plug. Then I will cut the spark plug port down inside the chamber to match the plug evenly all the way around. Yes I'm getting a bit anal with the details but it's all apart and I might as well take the extra few minutes and do what I can to better flame propagation. It also doesn't cost me a thing. Even if it doesn't remotely increase power to some millionth degree it will still help eliminate detonation problems from hot spots next to the plug. Anyways back to the CR point. If one was to buy a 300cc kit and also have the jug shaved .050... you'd have a CR somewhere around 10.4 to 10.5 fyi.
|