Will this LS7 valvetrain live?
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Teching In
Joined: Nov 2003
Posts: 10
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From: Frozen MN
Will this LS7 valvetrain live? The PRC heads with upgraded 1.351od .700 lift 180lbs on the seat 460lbs open. Comp lsl Lobe @ .661 lift & harlan sharp upgraded rockers. I just woke up scared about this. Any body wanna share there thoughts.
Registered User
Joined: Jan 2009
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A couple years ago I put together a 438" wet sump LS7 using stock LS7 heads along with Chevy's Del West Ti intake and hollow stem exhaust valves. I used PSI 1511 springs with less pressure than yours and a COMP XER lobe cam with .650" lift. I mocked up the engine and used .80" thick Manley lash caps for the intakes and machined .040" eucentric rocker arm shims for the exhausts to get the wipe patterns perfectly centered. I used appropriate length 3/8" push rods for a .060" preload with Caddy lifters. After 5500miles I pulled the heads this winter to check things over.
I was surprised to find that the thickness of four of the Manley lash caps had worn down to .050 - .055" (from .080"). I replaced all 8 caps with another vendor's .080" lash caps. I also found that all the iron valve had worn more than I would have liked though they were still useable.
On a plus note, the coating on the Ti intake valves hadn't worn at all on the stems or valve face. The exhaust valve's stems and face hadn't worn either.
Keep you eye on the lash caps if you use them and on valve guide wear.
I was surprised to find that the thickness of four of the Manley lash caps had worn down to .050 - .055" (from .080"). I replaced all 8 caps with another vendor's .080" lash caps. I also found that all the iron valve had worn more than I would have liked though they were still useable.
On a plus note, the coating on the Ti intake valves hadn't worn at all on the stems or valve face. The exhaust valve's stems and face hadn't worn either.
Keep you eye on the lash caps if you use them and on valve guide wear.
TECH Fanatic
Joined: Jun 2002
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From: Upstate NY
Who designed your valvetrain? What did they advise for retainers and pushrods? Stock LS7 valves?
