Hey, why are “rocker arm stoppers” recomended when upgrading the camshafts of a sr20det? DOHC engines aren’t supposed to have rocker arms?
Could someone explain this to me?
Maybe even with a few pics?
Thanks
The rocker arm stopper is a metal arm that hangs down over the rocker arms to prevent them from popping off at high rpm. And since the aftermarket cams increase lift and duration, the rocker arm stoppers are suggested for a safety measure. They don’t replace anything or serve any mechanical purpose. They just sit there and do their job… stop the rocker arms from popping off.
I have them on my car with the HKS cams, and they took like 10 minutes to install if you know what your doing.
But that doesn’t answer why the engine has rocker arms in the first place.
Most other 4 banger DOHC engines don’t have rocker arms, just direct camshaft to valve conection. How/why are sr20det’s differnt?
There is no direct camshaft TO valve conection. There is always something in there whether it be a rocker arm, cam follower, whatever. You would bust the head of the valve off if it was a direct connection. An engine has rocker arms for that reason, to transfer camshaft lobe movement to the valve. If you look, on some rocker arms, depends on the style, the rocker arm has a large shiny spot on the top. This is the surface area the camshaft lobe rotates on. If it was a DIRECT camshaft lobe to valve, it wouldn’t happen. There isn’t enough surface area for the camshaft to open the valve.
I see, that makes sense.
Thanks!!
I was answering this part. lol.