Valve spring cup
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Valve spring cup
What would cause a valve spring cup to break in half? I just pulled the number one springs off for height checking and discovered the intake spring cup in two pieces. The spring psi is down but not sure if that would cause it. the exhaust has a .015 shim under it and both look fine. Ideas?
cool40- BBF CONTRIBUTOR
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Re: Valve spring cup
rebuilt.......Lem Evans wrote:Did it have a salvage title?
cool40- BBF CONTRIBUTOR
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Re: Valve spring cup
Sounds like a root beer float to me.....
dfree383- BBF CONTRIBUTOR
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Re: Valve spring cup
I suspect a couple of wise guysdfree383 wrote:Sounds like a root beer float to me.....
cool40- BBF CONTRIBUTOR
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Re: Valve spring cup
you have a spring in mind?Lem Evans wrote:Spring float.
cool40- BBF CONTRIBUTOR
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Re: Valve spring cup
1.75 and .850 lift without the lash. Im thinking the springs dropping psi did the damage. Intake valve is big..... .Lem Evans wrote:What is your rocker ratio?
cool40- BBF CONTRIBUTOR
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Re: Valve spring cup
What's the valve tip and rocker roller tip look like?
dfree383- BBF CONTRIBUTOR
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Re: Valve spring cup
round and shiny. ... rockers look new.I thought the valves had a few different marks on them like they were turning but not really sure. The hardened tips are hard for me to see any marks on.dfree383 wrote:What's the valve tip and rocker roller tip look like?
cool40- BBF CONTRIBUTOR
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Re: Valve spring cup
That may be the best. Maybe advancing the cam will get the rpm back under control.Lem Evans wrote:You have a PAC 1228 spring ?
If so, run it closer to coil bind.
cool40- BBF CONTRIBUTOR
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Re: Valve spring cup
cool40 wrote:round and shiny. ... rockers look new.I thought the valves had a few different marks on them like they were turning but not really sure. The hardened tips are hard for me to see any marks on.dfree383 wrote:What's the valve tip and rocker roller tip look like?
Star pattern on the valve tip?
dfree383- BBF CONTRIBUTOR
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Re: Valve spring cup
dfree383 wrote:cool40 wrote:round and shiny. ... rockers look new.I thought the valves had a few different marks on them like they were turning but not really sure. The hardened tips are hard for me to see any marks on.dfree383 wrote:What's the valve tip and rocker roller tip look like?
Star pattern on the valve tip?
cool40- BBF CONTRIBUTOR
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Re: Valve spring cup
Tough to see...... Any marks on the keepers? Hard to get off?
dfree383- BBF CONTRIBUTOR
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Re: Valve spring cup
not really.....I didn't run it much last year but did check the springs. A couple were less tha others but none under 260#. I'm Thinking where it "wanted " to run was above the happy place for the springs. Also like Lem said I should have had them closer to coil binding. I didn't check them when new but they should have been 300# @ 2.070.dfree383 wrote:Tough to see...... Any marks on the keepers? Hard to get off?
cool40- BBF CONTRIBUTOR
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Re: Valve spring cup
cool40 wrote:That may be the best. Maybe advancing the cam will get the rpm back under control.Lem Evans wrote:You have a PAC 1228 spring ?
If so, run it closer to coil bind.
You may be better to run the 1224 spring that set at 2.00"......at least on the exh. side.
Exh. lobe lift?
Re: Valve spring cup
exh lift is 810 wo lash i think. I also remember putting +.050 locks on it so I could change them instead of shimming for the 1228's. I'd take a little more psi to keep from beating on the valve train at 7800-8000 rpm.Lem Evans wrote:cool40 wrote:That may be the best. Maybe advancing the cam will get the rpm back under control.Lem Evans wrote:You have a PAC 1228 spring ?
If so, run it closer to coil bind.
You may be better to run the 1224 spring that set at 2.00"......at least on the exh. side.
Exh. lobe lift?
cool40- BBF CONTRIBUTOR
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Re: Valve spring cup
Agreed, use the locks instead of a herd of shims.
When the spring is operated way above coil bind the open load is to light.
When the spring is operated way above coil bind the open load is to light.
Re: Valve spring cup
It's been running @ .120 from coil bind. 1228's with std locks will put me @ .070....
cool40- BBF CONTRIBUTOR
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Re: Valve spring cup
cool40 wrote:It's been running @ .120 from coil bind. 1228's with std locks will put me @ .070....
But, the exh. will still be ~ 1/8" above c.b.
Re: Valve spring cup
i am by no means an expert when choosing valve springs. but is that weld in that area by the spring cup....? maybe machined wrong after the repair...?
torino501- Posts : 417
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Re: Valve spring cup
casting flaw where the water plug hole was.nice welding job though.torino501 wrote:i am by no means an expert when choosing valve springs. but is that weld in that area by the spring cup....? maybe machined wrong after the repair...?
cool40- BBF CONTRIBUTOR
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