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Ted
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Doug T (1/9/2010)
I doubt that the y's rocker arm itself is a lot heavier than the stamped ball joint rockers for small blocks. Ted, can you confirm?Doug. Took some doing but actually found a stock scrub rocker here. It weighs in at 92g without the fulcrum.
  Lorena, Texas (South of Waco)
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Doug T
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Just to pile on a little, assuming those holes are 1/8" dia and through 1/8" of material they represent the removal of about 1.2 grams of steel. As usual Charlie Burns done it right with a far larger weight reduction. The idea of reducing Y block valve train weight seems to me to be a result of the old HRM mantra that the y block wouldn't rev because of heavy valve train components. This was shown to be a result of the crappy solid pushrods which were not stiff enough to act as a good column. I doubt that the y's rocker arm itself is a lot heavier than the stamped ball joint rockers for small blocks. Ted, can you confirm?
Doug T The Highlands, Louisville, Ky. 
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Hoosier Hurricane
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With all the talk about saving valve train weight, remember the biggest gains will be in the portion from the rocker shaft outward, since these pieces move the farthest, hence faster. So to save weight where it will be significane, go to titanium valves, and as Frank said, titanium retainers and beehive springs. How light can you afford to go on a street engine?
John - "The Hoosier Hurricane"
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Ted
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The aluminum rockers are bulkier in part due to just getting the strength back. I have yet to run the Harland Sharp rockers for an evaluation but when I do, I’ll be limiting the rpms to 5500 so I may or may not see a problem with them being heavier. As compared to the Dove rockers, the Harland Sharp rockers have a wider roller tip which is also larger in diameter and that is a player on the increase in weight on this particular rocker. These rockers are also just beefier looking all over compared to the Doves. I’ll finish up with the spacers today for the Harland Sharp rockers and then be ready to run these rocker assemblies in the near future. Up until yesterday the test engine hadn’t been responsive to changes but headway was made yesterday when I removed the Red’s headers that had 2” head pipes and installed the headers from the EMC engine with mufflers. Picked up a clean twenty two horsepower at which point I started trying out different ratio rocker arms again. Now the engine was more responsive and this engine still has the dead stock unported G heads.
Lorena, Texas (South of Waco)
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charliemccraney
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It's interesting that the aluminum rockers don't look much better on paper. They obviously work for high RPM. I guess the bulk of their mass is closer to the shaft center-line. That shows the effect that the distribution of the mass can have.
Lawrenceville, GA
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Ted
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As Frank brings up, the weight reduction of components is synominous to an increase in rpms but so are the modern lobe profiles being used in current camshaft design. For stock stuff, the rocker arm weights are typically not an issue unless the valve springs are getting weaker as time goes along at which point a rocker with less mass would keep you out of valve float a little longer. The EMC engine was being buzzed to 7400-7500 rpms so there was a real need for a valve train that would sustain this kind of rpm without the destructive harmonics associated with a heavier valve train. Here are some weights of the various rocker arms: 124 g - 1.54:1 ECG with screw adjuster and locknut 113 g - 1.54:1 ECG with hollow screw adjuster 146 g – 1.43:1 EAN with screw adjuster and locknut 120 g – 1.43:1 ‘575’ with screw adjuster and locknut 109 g – 1.43:1 ‘575’ with hollow screw adjuster 63 g – 1.4:1 Thomas magnesium with locknutted adjuster 70 g – 1.6:1 Thomas magnesium with locknutted adjuster 112 g – 1.6:1 Dove aluminum with locknutted adjuster 153 g – 1.65:1 Harland Sharp aluminum prototype with locknutted adjuster
Lorena, Texas (South of Waco)
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pegleg
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Danny, Of course it would. Today we have Dove aluminum rockers (Ted's roadster and the EMC entry) as well as Beehive springs, stainless valves, Titanium retainers etc. Actually the stainless valves are heavier than plain steel. But my point being, for a practical street motor, you don't gain much with this stuff. Different story on a 9 second roadster. Your theorey is correct, simple Physics, but for practicality???????? Those rockers were probably done 50 years ago when nothing else was available. Drill 'em till they break and do the next set with one less hole! Also, as Ted and John will tell you, we've probably gained more with intelligent cam design than anything else.
Frank/Rebop Bristol, In ( by Elkhart) 
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DANIEL TINDER
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Dan,
The undrilled, locknut style factory 1.54's on my F code go 6500 with no sign of float. Begs the question why would you need anything more for street use?[/quote]
Good question. Would lighter valve gear allow the use of weaker springs & more valve lift (more aggressive lobe/higher rocker ratio) in order to rev as high without float, thereby prolonging cam/lifter wear?
6 VOLTS/POS. GRD. NW INDIANA
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aussiebill
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Frank, exactley! Thought you might like pic of these Fenton rocker arms from my collection, they are new and probably could power a mack truck, they are thick and heavy, approx 6 oz,s compared to 4 oz normal, they have offset rib on top to let oil spray toward center of tip. Also i cant find them at moment but i also lightened the normal rocker arm at the tip like an FE rocker, that narrows the excess unused pad width once the arms are centered on valve tip, quite a weight reduction. best regards bill. 
 AussieBill YYYY Forever Y Block YYYY
Down Under, Australia
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pegleg
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DANIEL TINDER (1/8/2010)
Frank,
Since frequent lash adjustment usually results in sloppy interference-fit/friction adjusters that eventually need jamb nuts, drilling them out would seem strongly indicated to compensate for the added weight. Something that could be accomplished safely with home tools, of best left to a machine shop?
I also see a market opportunity for someone to provide pre-drilled (or light alloy), oversized thread adjusters (John M.?), as every Y-Blocker would likely want to snap some up if they were available?Dan, The undrilled, locknut style factory 1.54's on my F code go 6500 with no sign of float. Begs the question why would you need anything more for street use?
Frank/Rebop Bristol, In ( by Elkhart)
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