Tuning tips: Performance valve springs

[obi_waynne]

The valve springs pull the valves up#!when they are closed thereby sealing the valve. The camshaft pushes the valve open against the spring. As you can imagine this is a high wear high stress component of the engine.#! They need to be fitted using a valve spring compressor - any other attempt at installing them […]
More...

What do you think of this tip then, read the article and post your comments in here.

 

[HDi fun]

Double valve springs are pretty commonplace in factory engines these days. The idea being that the two springs have different resonant frequencies, thus reducing (ideally eliminating) valve bounce as revs rise.

My Nissan Primera was setup this way, as was the BMW M52TUB28 engine in my late 528i. Neither had outrageously high rev capability, Nissan's SR20De revved to about 6700rpm, the BMW to about 6300rpm. But they both did so happily and without mechanical issues.