Dual valve springs going to hurt my performance?
10-08-2007, 12:09 PM
#1
Jedi Master
Thread Starter
iTrader: (3)
Join Date: Apr 2007
Location: MN
Posts: 668
Likes: 0
Received 0 Likes
on
0 Posts
Dual valve springs going to hurt my performance? I went with Patriot Gold springs for my cam because of all the problems with the 918 springs lately. Is it too much spring that it will lower my power output?
Cam:
226/228 581/585
Cam:
226/228 581/585
Trending Topics
10-08-2007, 05:19 PM
#8
TECH Fanatic
iTrader: (3)
Join Date: May 2003
Location: Lake Anna, VA/ Fairmont, WV
Posts: 1,795
Likes: 0
Received 0 Likes
on
0 Posts
Crane says that higher spring pressure will not lose any hp over a spring with less pressure. They make awesome products and perform alot of testing.
From Crane's website......
"Many people mistakenly think that using higher seat pressures causes a reduction in the horsepower delivered to the flywheel because higher seat pressures (and also higher spring rates required for high performance) require horsepower to compress the springs. This thinking is simply incomplete! For every valve that is opening and its valve spring being compressed, another valve is closing and its valve spring is expanding. This expansion returns the energy to the valve train and the engine. This results in a net power loss of "0" hp. Many engineering texts refer to this as the "regenerative characteristic" of the valve train. Recent tests at Crane have shown no horsepower loss on a hydraulic roller equipped engine when changing the seat pressure from 135# to 165#. Power actually improved significantly at top end, probably due to better control of the relatively heavy valves in the engine.
In Summary:
Always run enough seat pressure to control the valve action as it returns to the seat. Heavier valves require more seat pressure. Strong, lightweight valves require less seat pressure. When in doubt, run slightly more seat pressure . . . not less. "
From Crane's website......
"Many people mistakenly think that using higher seat pressures causes a reduction in the horsepower delivered to the flywheel because higher seat pressures (and also higher spring rates required for high performance) require horsepower to compress the springs. This thinking is simply incomplete! For every valve that is opening and its valve spring being compressed, another valve is closing and its valve spring is expanding. This expansion returns the energy to the valve train and the engine. This results in a net power loss of "0" hp. Many engineering texts refer to this as the "regenerative characteristic" of the valve train. Recent tests at Crane have shown no horsepower loss on a hydraulic roller equipped engine when changing the seat pressure from 135# to 165#. Power actually improved significantly at top end, probably due to better control of the relatively heavy valves in the engine.
In Summary:
Always run enough seat pressure to control the valve action as it returns to the seat. Heavier valves require more seat pressure. Strong, lightweight valves require less seat pressure. When in doubt, run slightly more seat pressure . . . not less. "
10-09-2007, 12:36 AM
#14
That's awesome. I snapped my kanuter valve once with dual springs, just to warn everyone, make damn sure you check the blinker fluid before you install them or you'll end up like me...
Seriously - "takes power to make power" isn't always 100% true, especially in this case... blowers, yes. Don't even sweat it... MAYBE if you were trying to run a spring good for 1" lift on a .550" lift cam, I could see a problem with a seat pressure of 1000# open, we're talking a few hundred here max. Don't sweat it, PRC makes a good dual spring setup, very nice, I have those on my ported 6.0's for my 408.
Seriously - "takes power to make power" isn't always 100% true, especially in this case... blowers, yes. Don't even sweat it... MAYBE if you were trying to run a spring good for 1" lift on a .550" lift cam, I could see a problem with a seat pressure of 1000# open, we're talking a few hundred here max. Don't sweat it, PRC makes a good dual spring setup, very nice, I have those on my ported 6.0's for my 408.
