Dumb bell solid lifters

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Did the solid lifter become shaped like a dumb bell????

Are solid lifters lacking intelligence (certainly not as smart as hydraulic lifters that can figure out how much gap to take up) there by being dumb bells?

Inquiring minds what to know!
 
depends on the lift, or rather the "sink" of the lifter as all LA's lift is based on base circle. Stock 64 273 pictured...
lifter.jpg
lifter2.jpg
 
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depends on the lift, or rather the "sink" of the lifter as all LA's lift is based on base circle. Stock 64 273 pictured...View attachment 1715222398 View attachment 1715222399

Thanks Pishta. I've been pondering your drawing. The oil gallery is about .600" down the lifter boss so the gallery is exposed to the cut out any time the lifter isn't riding on the lobe and at that point some oil must slosh around the lifter body. I've looked at a standard factory cam which measures a base circle of 1.34, a Racer Brown ST21 with a base circle of 1.21 and a Lunati hyd Voo Doo at 1.19". I also measured a standard hyd lifter at 1.89 and a Rhoads lifter at 1.89".

So we have a maximum difference of .060" lifter height between the generic hyd and 273 Dumbells - big deal. The maximum difference between the smallest base circle (the Voodoo) and the dumb bell lifter height is around .150" so really it should work. The next step is to buy the Comp Cams Magnum 20-248-4 solid cam and a dumb bell and physically have a look. If the lifter doesn't allow the oil gallery to be exposed and it sits a little deeper the the lifter boss that will also help with the push rod angle.
Cheers
 
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the aftermarket cams also spec a longer pushrod as every one I've seen sold for the mechanical valvetrain is longer than the stocker. Makes sense as they all have a lower base circle. I have heard the myth that the dumb-bell lifters will window the oil galley too on a high lift cam. Im thinking the 273/2 cam had a lobe lift of .405 (ex) so the lifter bore is going to be .499 above the base circle: (.270+.229 rust band)~ .405/1.5=.270 lift at cam. So theoretically the max lift (drop) of a dumb-bell lifter ON A 273/2 BASE CIRCLE is .290 or .435 valve lift which is shorter than every factory 4bbl cam ('cept the 273/4), all hydraulic.. Maybe no myth? I dont know the base circle of a 273/2 cam though, is it really 1.34? so we can do some more math.....LA cam bearing Id is about 1.956 (smallest one lobe has to go through, #4). so any lift you have is going to drop the base that much / 1.5 (rocker ratio). Lunati at a 1.19 base circle has a max lobe lift of .383 or a .574 lift.
 
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somewhere I see a .551 (.780 lower band minus .229 rust area) as the max lobe lift (.826 at valve!!) a dumbell can do without exposing the oil band...? Im spinning.....Yeesh, this should be called Motor math...
 
Custom pushrods. Problem solved.
 
Jus asking, but the 284/484 is a hydro right?; will the ramps on it survive with running solids on them?

I did run the solids on a 1973 teener cam, no problem, but that is a different story.
 
I would not run solids on a 284/484 hydro cam but the intensity is low enough you could get away with it
but why
It's not like running a class with a "stock" cam rule
 
Jus asking, but the 284/484 is a hydro right?; will the ramps on it survive with running solids on them?

I did run the solids on a 1973 teener cam, no problem, but that is a different story.
No it's a solid lifter camshaft
 
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