Valve springs needed.
#1
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Valve springs needed.
Cam is a Trick Flow 228/230 585/585 with 243 heads on a LQ4 shortblock.. I was thinking the PAC single springs but the limit is only 600. Is there usually a "margin" there should be from max lift on the cam to max lift for the spring? I've run the 918's with good luck on my Vortec headed marine engine but never on an LS engine. I've heard of the springs breaking but also ehard that problem was taken care of. Thoughts?
#2
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In addtion to their .600 lift spring, PAC also makes a single beehive spring rated for .650 lift if you don't want to go with duals.
http://www.texas-speed.com/shop/item...=1065&catid=48
http://www.texas-speed.com/shop/item...=1065&catid=48
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i found this link for you. i hope it helps in your selection. there is more to it then just the springs rated lift. check it out. http://www.kennedysdynotune.com/Valv...ing%20Tech.htm
#4
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i found this link for you. i hope it helps in your selection. there is more to it then just the springs rated lift. check it out. http://www.kennedysdynotune.com/Valv...ing%20Tech.htm
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#6
We just had a thread like this. The springs rated lift already has a safety factor. As long as you're using the springs in the recommended application, you should fine, esp. with PAC products.
1218's coil bind at 1.140, installed at 1.8 gives you .660 lift max. Minus your .060 safety factor, and you've got the .600 rated lift. Pressures of 130/318 as a beehive are plenty unless you're revving to the moon with 6.0 valves. If you want more pressure, shim it to get to max rated lift. At that point you have to KNOW you cam's lift is correct, along with the installed height the same for all the valves.
New 918's are rated to .625, and coil bind at 1.110.
1218's coil bind at 1.140, installed at 1.8 gives you .660 lift max. Minus your .060 safety factor, and you've got the .600 rated lift. Pressures of 130/318 as a beehive are plenty unless you're revving to the moon with 6.0 valves. If you want more pressure, shim it to get to max rated lift. At that point you have to KNOW you cam's lift is correct, along with the installed height the same for all the valves.
New 918's are rated to .625, and coil bind at 1.110.
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Cam is a Trick Flow 228/230 585/585 with 243 heads on a LQ4 shortblock.. I was thinking the PAC single springs but the limit is only 600. Is there usually a "margin" there should be from max lift on the cam to max lift for the spring? I've run the 918's with good luck on my Vortec headed marine engine but never on an LS engine. I've heard of the springs breaking but also ehard that problem was taken care of. Thoughts?
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#9
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Springs should be based off of measured coil bind height.