Valve spring?
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From: Barto PA
Valve spring? I got 317 heads that look to have triple springs per valve. I bought a .608 lift cam and I'm pretty sure the valve springs will work but not sure.
Anyway to check while the heads are off and springs installed?
Anyway to check while the heads are off and springs installed?
As above, I doubt that there's three springs. Could be 2 springs and a damper, though. Does the inner most spring have more of a flat steel look than the other two? If so, it's a damper and not a spring.
Regardless of how many springs it has, it may or may not be set up to handle .608" of valve lift. The only way to know for sure is to remove the spring and measure with a micrometer. If you're really carefull, you can measure the instaled height with the spring installed. But unless you know the specific part number for the spring you're guessing on the coil bind height.
Valve spring force is a trade off. If you plan on running a lot of lift at sustained high rpm's, then you need a lot of spring pressure to close the valves quickly to prevent valve train float. Along with those heavy springs you need some hefty push rods to prevent the pogo effect. The down side of all that is that the springs are heavy, it takes a lot of energy to work the valve train, and things tend to wear out quickly.
OTOH, if you're building a street engine that won't see 7,500 rpm's, maybe you don't need such heavy springs. A good beehive spring with light weight retainers and smaller push rods might be a better choice for you.
Regardless of how many springs it has, it may or may not be set up to handle .608" of valve lift. The only way to know for sure is to remove the spring and measure with a micrometer. If you're really carefull, you can measure the instaled height with the spring installed. But unless you know the specific part number for the spring you're guessing on the coil bind height.
Valve spring force is a trade off. If you plan on running a lot of lift at sustained high rpm's, then you need a lot of spring pressure to close the valves quickly to prevent valve train float. Along with those heavy springs you need some hefty push rods to prevent the pogo effect. The down side of all that is that the springs are heavy, it takes a lot of energy to work the valve train, and things tend to wear out quickly.
OTOH, if you're building a street engine that won't see 7,500 rpm's, maybe you don't need such heavy springs. A good beehive spring with light weight retainers and smaller push rods might be a better choice for you.
Thread Starter
Tire Smoking Tranny Blowing Director
iTrader: (2)
Joined: Nov 2001
Posts: 2,130
Likes: 1
From: Barto PA
As above, I doubt that there's three springs. Could be 2 springs and a damper, though. Does the inner most spring have more of a flat steel look than the other two? If so, it's a damper and not a spring.
Regardless of how many springs it has, it may or may not be set up to handle .608" of valve lift. The only way to know for sure is to remove the spring and measure with a micrometer. If you're really carefull, you can measure the instaled height with the spring installed. But unless you know the specific part number for the spring you're guessing on the coil bind height.
Valve spring force is a trade off. If you plan on running a lot of lift at sustained high rpm's, then you need a lot of spring pressure to close the valves quickly to prevent valve train float. Along with those heavy springs you need some hefty push rods to prevent the pogo effect. The down side of all that is that the springs are heavy, it takes a lot of energy to work the valve train, and things tend to wear out quickly.
OTOH, if you're building a street engine that won't see 7,500 rpm's, maybe you don't need such heavy springs. A good beehive spring with light weight retainers and smaller push rods might be a better choice for you.
Regardless of how many springs it has, it may or may not be set up to handle .608" of valve lift. The only way to know for sure is to remove the spring and measure with a micrometer. If you're really carefull, you can measure the instaled height with the spring installed. But unless you know the specific part number for the spring you're guessing on the coil bind height.
Valve spring force is a trade off. If you plan on running a lot of lift at sustained high rpm's, then you need a lot of spring pressure to close the valves quickly to prevent valve train float. Along with those heavy springs you need some hefty push rods to prevent the pogo effect. The down side of all that is that the springs are heavy, it takes a lot of energy to work the valve train, and things tend to wear out quickly.
OTOH, if you're building a street engine that won't see 7,500 rpm's, maybe you don't need such heavy springs. A good beehive spring with light weight retainers and smaller push rods might be a better choice for you.