Effect of tightening valve springs?
Effect of tightening valve springs?
i was talking to a buddy who builds cars and he told me if i want a simple fix to add hp that i should tighten up my valve springs. he said it adds 5-8hp but uses up a little more gas. is this true? is there any side effects to this? i am about to put on a turbo later this week. will it help out my kit? any info is appreciated.
Tighten valve springs?
Valve springs are held in by retainers and 2-part keepers. There is no way to tighten them. Unless you machine the stem to set the keepers lower.
Quite frankly I fail to see the point in this. By tightening the springs you are changing the spring rate (assuming they are progressive), which isn't a great idea. I don't see how this would add more power. The only reason you may want stiffer valve springs for is to eliminate valve float at high rpms. In which case you should buy springs especially for this purpose.
Valve springs are held in by retainers and 2-part keepers. There is no way to tighten them. Unless you machine the stem to set the keepers lower.
Quite frankly I fail to see the point in this. By tightening the springs you are changing the spring rate (assuming they are progressive), which isn't a great idea. I don't see how this would add more power. The only reason you may want stiffer valve springs for is to eliminate valve float at high rpms. In which case you should buy springs especially for this purpose.
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C-Kwik
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This kind of depends on what is meant by tightening valve spriongs. If you are merely talking about bringing valve lash back to specs, then it certainly can add a bit of power, but it';s not adding it as much as it's giving you back lost power.
If you are referring to stiffening the valve, you are now creating more resistance for the cam to overcome. You will also increase the friction between the lifter and the cam. Your friend sounds like he's full of crap...
If you are referring to stiffening the valve, you are now creating more resistance for the cam to overcome. You will also increase the friction between the lifter and the cam. Your friend sounds like he's full of crap...
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Ubernoober
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I don't know that his friend is full of crap, I just think he is not explaining himself fully. Not only that, I think his friend is transferring some little tidbit he learned about one car to every other car he comments on.On my solid lifter V8's If I adjust my lash tighter by a few thousandths I can gain some (small, barely measurable) power.On the KA, it is designed to use shims. You could shim it tighter, but your gains would be unmeasurable. The system is simply not built in a way to make any use of tighter clearances.