Weight of Small Block Chevy Valvetrain Components

Chris Hill · 06-16-2008, 03:45 PM

Bill, you are 100% correct. However, for a pushrod type valvetrain, the general rule of thumb is 1/3 of rocker arm mass should be applied to valvetrain effective mass measured at the valve.

The combustion pressure can be ignored as once the valve is cracked, the pressures psudo equalize on both sides of the valve and the net force is realtively low compared to inertia force and valvespring force. You have to watch valve spring load on the seat with boosted applications. The boost wants to push the valve off the seat.

I'm estimating the safety factor for the rocker arm. If I'm off a little bit, does not matter much, as the safety factor will come in around 3~4:1. If the safety factor is 1:1, then things are more critical.

06-16-2008, 03:45 PM	#6
Chris Hill Senior Member Join Date: Jan 2002 Posts: 654 Likes: 8 Liked 244 Times in 26 Posts	Re: Weight of Small Block Chevy Valvetrain Components Bill, you are 100% correct. However, for a pushrod type valvetrain, the general rule of thumb is 1/3 of rocker arm mass should be applied to valvetrain effective mass measured at the valve. The combustion pressure can be ignored as once the valve is cracked, the pressures psudo equalize on both sides of the valve and the net force is realtively low compared to inertia force and valvespring force. You have to watch valve spring load on the seat with boosted applications. The boost wants to push the valve off the seat. I'm estimating the safety factor for the rocker arm. If I'm off a little bit, does not matter much, as the safety factor will come in around 3~4:1. If the safety factor is 1:1, then things are more critical. __________________ Chris Hill https://ihmusedparts.com Last edited by Chris Hill; 06-16-2008 at 03:49 PM. Reason: spelling