318 cam
Also, you don't "grind" the guides. Lets use the correct terminology here, since you are wanting to learn. They are cut with a special cutter. There are several different sizes. Which valve spring you choose needs to be a deciding factor based on the ID of the valve spring. This is an example of the type of tool that I use for the job. It will cut the OD of the valve guide, cut the top down and also will enlarge the spring seat all at the same time. Although it will also cut the spring seat deeper, at NO time whatsoever do I recommend THAT. There are different tools that will do the same job(s) but this is similar to the style that I use. I don't think the one in this picture will cut the top of the guide down, but mine does.
Also, you don't "grind" the guides. Lets use the correct terminology here, since you are wanting to learn. They are cut with a special cutter. There are several different sizes. Which valve spring you choose needs to be a deciding factor based on the ID of the valve spring. This is an example of the type of tool that I use for the job. It will cut the OD of the valve guide, cut the top down and also will enlarge the spring seat all at the same time. Although it will also cut the spring seat deeper, at NO time whatsoever do I recommend THAT. There are different tools that will do the same job(s) but this is similar to the style that I use. I don't think the one in this picture will cut the top of the guide down, but mine does.