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rocker arms Stud or Shaft, Crane or Comp

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Old 12-26-2011, 11:21 AM
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I think I would agree here on maybe a little bit of overkill using the T&D shaft system on these N/A mild build engines.
Good ARP studs, stainless roller rockers and some stud girdles should give you all the stability and life you need for .600 lift hydraulic roller and 5800rpms. Make sure the oiling is good as this item overlooked kills a lot of valve train on BBC's , stay with fairly light valve weights,obviously put good money in proper springs,cnc'd retainers,locks and put good valve guides and valve guide clearances where they need to be. Also take time and effort to get pushrod lengths correct and set rockers arm contact patches properly on the top of the valve including guide plate left right alignments.
A lot of valvetrain wear, issues and failures that arise come from things other than the rocker arms at mild rpms.

Best Regards,
Ray @ Raylar

Last edited by Raylar; 12-26-2011 at 07:39 PM.
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Old 12-26-2011, 12:02 PM
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Originally Posted by Raylar
I think I would agree here on maybe a little bit of overkill using the T&D shaft system on thse N/A mild build engines.
Good ARP studs, stainless roller rockers and some stud girdles should give you all the stability and life you need for .600 lift hydraulic roller and 5800rpms. Make sure the oiling is good as this item overlooked kills a lot of valve train on BBC's , stay with fairly light valve weights,obviously put good money in proper springs,cnc'd retainers,locks and put good valve guides and valve guide clearances where they need to be. Also take time and effort to get pushrod lengths correct and set rockers arm contact patches properly on the top of the valve including guide plate left right alignments.
A lot of valvetrain wear, issues and failures that arise come from things other than the rocker arms at mild rpms.

Best Regards,
Ray @ Raylar
+1
Very well put Ray!
Happy New Year!
Jim
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Old 12-26-2011, 06:57 PM
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Originally Posted by Raylar
I think I would agree here on maybe a little bit of overkill using the T&D shaft system on thse N/A mild

build engines.
Good ARP studs, stainless roller rockers and some stud girdles should give you all the stability and life you need for .600 lift hydraulic roller and 5800rpms. Make sure the oiling is good as this item overlooked kills a lot of valve train on BBC's , stay with fairly light valve weights,obviously put good money in proper springs,cnc'd retainers,locks and put good valve guides and valve guide clearances where they need to be. Also take time and effort to get pushrod lengths correct and set rockers arm contact patches properly on the top of the valve including guide plate left right alignments.
A lot of valvetrain wear, issues and failures that arise come from things other than the rocker arms at mild rpms.

Best Regards,
Ray @ Raylar
Thanks Ray and Jim

My engines are SCI's not N/A's. Cam lifts are .665's. Boost is 9lbs at full load. My original Cranes on one engine seem a little loose. ComP Ultras not so much. You still think stud rockers are OK? Pushrods are .080 Manleys.
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Old 12-26-2011, 07:28 PM
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Now with some more info about the engines ( I missed the SCI in your first post) I will change my recommendations. With supercharging and 9lbs of boost at that rpm and nearly .700 lift, the horsepower and pressure loadings will be a lot higher on the valvetrain. I think the shaft rocker system for those engines is a worth while upgrade and cost justified as higher spring rates and pressures will add stress to the rocker system. If spring pressures recommended with the camshaft grind with boost pressures at 9lbs are as high as I think they may be the valve train stresses will need a sturdier shaft support system and rockers. I also like valve spring oilers if you can see to use them and at higher sustained rpms, they really make spring packages and rocker systems last longer with less issues. Based on final open spring pressures the pushrod strength will also be big factor so be sure to use good aftermarket units from someone like Manton or a good equal . Keep the strength and material of the pushrod in mind more than just wall thickness. Sounds like a good high strength lightweight 7/16" diameter is in order. You may also be pretty close to what I consider the limit of .827" hydraulic roller lifters depending on your final spring pressures.. You may want to consider bushing the block for min. .842" lifters like those that Isky and Morel make for higher rpm and boost pressures from supercharged and turbocharged applications.

Best Regards,
Ray @ Raylar

Last edited by Raylar; 12-26-2011 at 07:40 PM.
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Old 12-29-2011, 10:01 PM
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Stud mount vs shaft mount---Have someone push you while standing on 1 foot vs 2 feet and you'll get the idea real quick
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Old 12-31-2011, 01:12 PM
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Originally Posted by KAAMA
Stud mount vs shaft mount---Have someone push you while standing on 1 foot vs 2 feet and you'll get the idea real quick
Well put. All the experts, Raylar, Maderia and Cam Motion agree shafts for my application is better and not a waste off $$. Ordering shafts from M. Kinetics
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Old 12-31-2011, 05:36 PM
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With a stud mount rocker arm system you need to buy the studs, and pushrod guide plates, and some applications may require a stud girdle system.

For a little more money, a shaft mount system already comes with the mounting hardware...besides already having a built-in stud girdle system (of sorts) just by the superior design and no need for pushrod guide plates, and proper alignment either. It's a pretty cool designed integrated system in one.

Last edited by KAAMA; 12-31-2011 at 05:40 PM.
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