Pushrod Length?
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From: Gold Country California
Pushrod Length? LS1, LQ9 Heads not milled. Gasket thickness whatever MLS are. Comp XER281HR-12 cam. Comp 875-16 lifters. Yella Terra non adjustable rockers. Bought Comp hi tech 7.400 (stock length) pushrods but they seem too short during the clay clearance check with no head gaskets. Heads will go on soon but not yet. Comps web site says that adjustable must be used with "R" lifters. What's up with that? The Yella Terra's are nice and don't want to replace them if I really don't have to. I have to assume the base circle is smaller. Need some education on this.
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From: Gold Country California
Originally Posted by PREDATOR-Z
Just get 850-16 lifters, sell the "R" ones
Did you do a WIPE test on the rockers and valves?
Did you do a WIPE test on the rockers and valves?
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From: BFE
Originally Posted by Lasershop
Motor is prepped to turn 8000. Lifters are a concern. WTF is a "WIPE" test? Pushrod length would still be in question wouldnt it?
With piston # 1 @ TDC remove the rockers. Color the top flat tip of the valves with a black (or other dark) marker. Reinstall the rockers. Turn the motor by hand 2>3 times (full revolutions). Remove the rockers on # 1 and read the marks left on the flat valve tips.
Centered wipe line means correct geometry.
Closer to intake wipe line and you need to shim the rocker stands
Further to exhaust wipe line and you need to shave the rocker stands.
Once the geometry is correct then you can measure preload on lifters and determine your p-rod length.
If you stick with "R" lifters, you absolutely need adjustable rockers.
BTW you should not be running 8K rpm with a hydraulic cam. You should go solid if you want those rpms.
