Valve spring pressures
09-28-2015, 01:47 PM
#21
Registered
09-28-2015, 03:17 PM
#22
Heres another article on springs. He doesnt mention specifics, but he does mention any serious bbc drag racing engine, should have 220lbs of seat pressure. I dont know too many serious bbc drag racing engines that shift at 6000rpm these days though, or too many using a hydraulic lifter setup
http://rehermorrison.com/tech-talk-3...ngs-the-thing/
Another article where he mentions how a mild camshaft for an endurance engine, can have a smooth valvetrain, but wont win at the dragstrip.
http://rehermorrison.com/tech-talk-4...n-revelations/
http://rehermorrison.com/tech-talk-3...ngs-the-thing/
Another article where he mentions how a mild camshaft for an endurance engine, can have a smooth valvetrain, but wont win at the dragstrip.
http://rehermorrison.com/tech-talk-4...n-revelations/
Last edited by MILD THUNDER; 09-28-2015 at 03:21 PM.
09-28-2015, 03:48 PM
#23
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iTrader: (1)
In response to whomever mentioned it, A lower rate spring does not close the valve easier.
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An impact gun is effective because of the impacts/ blows, much more than the torque it has. Sure way to beat up your valve, valve seats, and rest of the valvetrain is too let it turn into an impact gun.
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Valvesprings have mass. A lighter valvespring usually controls a valve better than a heavier spring, even if the heavier spring has a tad more pressure.
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Only real negative effect a valvespring that has a little more prssure than yoiu actually need is increased heat from the valvespring itself.
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Did you know that a valvesprings rate declines the hotter it gets and can/will go back to normal pressure when cooled off...obviously if you didn't beat the spring into submission.
Therefore, your psi's may be a good amt less while running than you think.
There's a chart I put up the other month on here, I forget where it is.
=====================================
An impact gun is effective because of the impacts/ blows, much more than the torque it has. Sure way to beat up your valve, valve seats, and rest of the valvetrain is too let it turn into an impact gun.
======================================
Valvesprings have mass. A lighter valvespring usually controls a valve better than a heavier spring, even if the heavier spring has a tad more pressure.
======================================
Only real negative effect a valvespring that has a little more prssure than yoiu actually need is increased heat from the valvespring itself.
======================================
Did you know that a valvesprings rate declines the hotter it gets and can/will go back to normal pressure when cooled off...obviously if you didn't beat the spring into submission.
Therefore, your psi's may be a good amt less while running than you think.
There's a chart I put up the other month on here, I forget where it is.
09-28-2015, 04:04 PM
#24
In response to whomever mentioned it, A lower rate spring does not close the valve easier.
=====================================
An impact gun is effective because of the impacts/ blows, much more than the torque it has. Sure way to beat up your valve, valve seats, and rest of the valvetrain is too let it turn into an impact gun.
======================================
Valvesprings have mass. A lighter valvespring usually controls a valve better than a heavier spring, even if the heavier spring has a tad more pressure.
======================================
Only real negative effect a valvespring that has a little more prssure than yoiu actually need is increased heat from the valvespring itself.
======================================
Did you know that a valvesprings rate declines the hotter it gets and can/will go back to normal pressure when cooled off...obviously if you didn't beat the spring into submission.
Therefore, your psi's may be a good amt less while running than you think.
There's a chart I put up the other month on here, I forget where it is.
=====================================
An impact gun is effective because of the impacts/ blows, much more than the torque it has. Sure way to beat up your valve, valve seats, and rest of the valvetrain is too let it turn into an impact gun.
======================================
Valvesprings have mass. A lighter valvespring usually controls a valve better than a heavier spring, even if the heavier spring has a tad more pressure.
======================================
Only real negative effect a valvespring that has a little more prssure than yoiu actually need is increased heat from the valvespring itself.
======================================
Did you know that a valvesprings rate declines the hotter it gets and can/will go back to normal pressure when cooled off...obviously if you didn't beat the spring into submission.
Therefore, your psi's may be a good amt less while running than you think.
There's a chart I put up the other month on here, I forget where it is.
09-28-2015, 04:10 PM
#25
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iTrader: (1)
Here's the sheet from PAC Springs that has a ton of info in it, including that of heat vs spring psi.
http://www.racingsprings.com/Multime...b/kb513103.pdf
http://www.racingsprings.com/Multime...b/kb513103.pdf
09-28-2015, 04:23 PM
#26
Here's the sheet from PAC Springs that has a ton of info in it, including that of heat vs spring psi.
http://www.racingsprings.com/Multime...b/kb513103.pdf
http://www.racingsprings.com/Multime...b/kb513103.pdf
Platinum Member
09-28-2015, 07:17 PM
#29
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iTrader: (1)
In fact, too little spring pressure is almost always the root cause of valvetrain failures. We spent a year studying valve springs using an Optron, a sophisticated electronic device that can precisely record valve motion and reveal valve float. We learned some shocking truths about valvetrain behavior at high rpm. Even with a relatively mild camshaft profile, the valves bounce on their seats before they close. If the spring is too light, the valve bounces uncontrollably. The valve hits the seat, rebounds, hangs in the chamber awhile, and the bounces erratically several more times. Imagine how hard this is on the valve and the rest of the valvetrain!
Once they heat up it`s probably more like 115, I think you need some spring oilers
I like my spring pressure like a like my mountains.. HIGH!
and I like my springs like I like my Beer .. COLD
09-28-2015, 07:29 PM
#30
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iTrader: (1)
Ice - in fact, some manufacturers are starting to use deeper spring pockets and/or 'cages' (my term) for the lower prt of the springs to hold oil. Helps keep temps down and controls harmonics a little better. As most know now, Cup and some other forms of endurance racing go one step much further, and that is to 'flood' the valve covers with oil.
Your choice of having spring oilers can only help...that's for sure.
Your choice of having spring oilers can only help...that's for sure.
