Comp 987's and valve float
Thread Starter
Le Mans Master
Joined: Oct 2001
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From: Southern Maryland Maryland
Comp 987's and valve float
When will the valves start to float when your using Comp 987s and an XER cam? So far I have taken the new combo to 7k and it feels really nice.
Phillip
Phillip
Team Owner
Joined: Oct 1999
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From: Guinness Its whats for B'fast JAWGA
CI 3-4-5-9 Veteran
Re: Comp 987's and valve float (Walt Donovan)
Duration #s are in his sig and http://web.ics.purdue.edu/~lgigliot/xe-r has the lobe information.
Racer
Joined: Feb 2001
Posts: 286
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From: Bayville NJ
Re: Comp 987's and valve float (Phil97SVT)
OK. Got the cam specs, got the spring specs from Comp web pg. What installed ht are the springs in at?
If you put them in at 1.780 that's about as tight as you'd want (.025 from coilbind) they'd only be about 128# on the seat. That's new. After break-in they'd be below 120#. I think you're very lucky to get 7000 out of it with a "quick" cam (steel valves, right?). You may still be floating the valves (bouncing, actually), even if it feels good. If it were my motor, after a couple 7000 runs, I'd pull a spring or two and look for signs of surge or loft into coilbind. Look at the underside of the retainer and the tops and bottoms of the spring wire. Retainer will get beat up from loft and spring wire will be shiny, top and bottom (between coils) from slamming together into coilbind)
[Modified by Walt Donovan, 1:01 PM 6/30/2003]
If you put them in at 1.780 that's about as tight as you'd want (.025 from coilbind) they'd only be about 128# on the seat. That's new. After break-in they'd be below 120#. I think you're very lucky to get 7000 out of it with a "quick" cam (steel valves, right?). You may still be floating the valves (bouncing, actually), even if it feels good. If it were my motor, after a couple 7000 runs, I'd pull a spring or two and look for signs of surge or loft into coilbind. Look at the underside of the retainer and the tops and bottoms of the spring wire. Retainer will get beat up from loft and spring wire will be shiny, top and bottom (between coils) from slamming together into coilbind)
[Modified by Walt Donovan, 1:01 PM 6/30/2003]
