Q: What is the spec for the cylinder head valve springs on Cummins B Series and C series engines? | 9/25/2024 |
A: The Cummins Repair Manual says that the free length of a valve spring should be around 55.63mm with a max inclination of 1.0mm. | |
Q: What is the tension spec for the cylinder head valve springs on Cummins B Series and C series engines? | 9/25/2024 |
A: The Cummins Repair Manual says that the valve spring tension should be a minimum load of 289.32 N to compress the spring to a height of 49.25mm. | |
Q: How many RPMs can the stock valve spring handle on a Cummins 5.9 6BT 12v engines? | 9/30/2024 |
A: The Haynes Repair Manual discusses this topic and talks about changing valve springs, if you want to go over 3000 RPM. This is especially true for engines with a lot of miles. The Haynes manual actually warns of engine destruction, if the valve springs don't get the valve back into place, before the piston comes up. Also, if you are turning up the boost, stronger valve springs are recommended. They recommend stiffer valve springs, if you want to run over 30 PSI of boost. | |