Quote:
Originally Posted by UT_EvoX
Sorry, but I'm going to call BS on this. Higher tension springs WILL cause your valvetrain to wear out faster. Fact. How much faster, hard to say, and one could say the extra wear is negligible but it will be happening. Puts extra wear on the camshafts as well... You argue as though he's going to be now pushing the engine to 8000+ rpm 24/7 where the upgraded springs in fact ARE beneficial to the health of the engine as they are avoiding piston-to-valve contact, but the reality is he's probably going to be spending the majority of the time in the 2000-4000 rpm range just cruising.
But like I said, the extra wear is negligible, but the way you just stated all of that sounds like a straight up sales ad. I gave the OP the realistic cons of running higher tension valve springs. Do the pro's outweigh the cons in my opinion, YES, but I'm also not trying to sell a product.
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There is a lot you aren't thinking about. Every time the valve closes it bounces on the seat. A more aggressive camshaft profile that challenges the capabilities of the OEM spring could cause more valvetrain wear than the heavier seat pressure of the aftermarket spring. If the valvetrain is out of control, not only is it going to beat up parts, you are missing out on horsepower that you could have with a properly setup spring combination. It isn't just about the lift of the cam or the rpm, but what about boost pressure. The OEM spring was designed for a specific operating range... 7600rpm, stock cam lobe, and 24psi. You start throwing in aggressive ramp speeds, more rpm, and more boost pressure that takes away from the seat pressure, and that valvespring is overwhelmed before you know it. An overwhelmed spring will fatigue really fast and lose its integrity. I have seen a spring lose 10lbs of seat pressure in 5 passes down the 1/4 just from a more aggressive ramp...no boost pressure. People don't often treat valvesprings as a wear item, but they are...just like brake pads and a clutch. They need replaced over time.
With these little valves, and steel seats, you don't need to worry about spring pressure beating up the seats. We run HUGE seat pressures on 37mm valve stuff and the seat is the last thing we worry about.
What we do run into with high pressure springs is deflection in the camshaft. All of the cheaper cams use cast cores and they are prone to a lot more flexing. Billet cores will not do this so much..but I don't know if anyone is using billets on X cams.