Larry in action! Polishing up those transfers.
If you want to get the most out of your kit, you better case match it. Smooth transitions from the case into the transfer ports will give you better performance overall. There are a couple schools of thought on how the match should flow, whether it be a gradual opening or deep cut into the case. Either way one thing should be the same, polish your matches very smooth.
We do most of our case matching in the middle of a rebuild, so at this point the engine has been taken apart and we are left with the case halfs. Its best to do this kind of mod now so we don’t get millions of aluminum shavings trapped in the engine forever. There are techniques to protect your engine from shavings if you had to case match without breaking down the engine… For another time.
Start out by making it very clear how much material you need to cut away. If your kit comes with a gasket, great. Make sure it matches your kit perfectly. If it does, use it as a “mask”. Put the gasket on the case halfs and use a Sharpie to mark the sections you will remove. Working with two separate case halfs may be tricky, so feel free to use a couple bolts to hold them together as one.
Once you have your marks, go to town with a Dremel and a Tungsten Carbide Cutter. Take your time. Steady hands. Wear eye protection. Try not to knick parts of the case you dont want altered, like where the case meets the cylinder. Use a masking tape if you dont have a steady hand or if you’ve been sipping Tacate.
When you have the shape you want switch to a grinding cylinder. Smooth out those imperfections. Switch to the little grinding nip for the edges and hard to reach spots.
Finish it off with a wire wheel for high polish touch. Send that fuel/air mixture down the red carpet!