So as I have been learning more about building engines, I have been digging more and more into camshafts. And it seems like the more I learn, the more I realize I don’t know.
So I thought I would start a series about camshafts to pass on what I have learned. And I thought it would be good to start with the basics.
First, I will mainly be covering the traditional American V8 with a single camshaft in the block and overhead valves.
The most common type of camshaft in traditional muscle car engines is a flat tappet. That means that the bottom of the lifter or tappet is flat.
Like this
There are two options for lifters like that, hydraulic and solid.
Solid are the simplest, they are a machined piece that makes a solid connection between the cam and the pushrod
Next are hydraulic lifters, and they have a small piston that is pushed up by the engine oil to eliminate the need to set valve lash.
And here is the more basic solid lifter:
Here is a roller hydraulic cam:
And a solid roller note the link bar to keep the lifters from rotating:
Here is a picture that shows the differences in the lobe shapes of flat and roller camshafts:
And here is a graph that shows the difference that shape change makes in how much the valve is open:
And there is a link to a web page that has some more pictures, and some cutaways of the types of lifters for your viewing pleasure – Lifters Link
As always, please leave feedback via comments, or email me at pat@themusclecarguy.net