4,400 HP !
02-11-2013, 01:44 PM
#12
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RACING JUNKIE
Join Date: Mar 2006
Location: EUGENE,OR.
Posts: 3,391
OK; forgive my ignorance here... but it is hard for me to comprehend this whole thing. MY question: in the first series of pics that Fla1976 posted- WTH is pic #2??? What is that thing... flux-capacitor?
02-11-2013, 01:47 PM
#13
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RACING JUNKIE
Join Date: Aug 2007
Posts: 1,523
Roller lifter.
Quote from Hot Rod "We dig the bolt-in lifter bushings, which make swapping them out a snap after you’ve nuked one. Drag Week Unlimited Class racers, are you listening? By the way the lifters have wheels that are over one-inch in diameter".
Quote from Hot Rod "We dig the bolt-in lifter bushings, which make swapping them out a snap after you’ve nuked one. Drag Week Unlimited Class racers, are you listening? By the way the lifters have wheels that are over one-inch in diameter".
02-13-2013, 05:52 AM
#14
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Join Date: Jan 2012
Posts: 628
Still want to see the head(s) . .
And if the Lifters have a 1" dia. Roller follower, what the hell does the Camshaft look like? It's gotta have lobes that resemble the counterweights on a SBC crankshaft . . I understand the need to cut bearing speed and increase the loading at the lifter (More valve seat pressure) but a radius like that isn't conducive to following a quarter inch radius on the ramps of todays long duration .800"+ lift "square lobed" cams, one would think . .
But then I was never very good at driving trains . . .
And if the Lifters have a 1" dia. Roller follower, what the hell does the Camshaft look like? It's gotta have lobes that resemble the counterweights on a SBC crankshaft . . I understand the need to cut bearing speed and increase the loading at the lifter (More valve seat pressure) but a radius like that isn't conducive to following a quarter inch radius on the ramps of todays long duration .800"+ lift "square lobed" cams, one would think . .
But then I was never very good at driving trains . . .
02-14-2013, 05:53 AM
#16
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RACING JUNKIE
Join Date: Jan 2012
Posts: 628
Yeah, I went back and looked at the picture of the block after I popped wise . . I'd guess that they're closer to 4" in diameter because they're actually bigger than the mains . .
Still, when you build a bigger lifter, you just create more reciprocating mass that has to change direction at high speeds and tremendous spring pressure . . so then you have to increase valve spring pressure, stronger rockers, bigger pushrods and more expensive one piece valves . . It's kind of a vicious circle . .
All the NASCAR guys are going the other way . . Little bitty cam lobes, little flat tappet lifters, skinny pushrods, and really high rocker arm ratios, 1:8/1:9 with 125# of seat pressure . . Dunno who's right, but their engines are built to go about 550 miles, while a drag racing engine spends more time being warmed than it does racing.
I guess us drag racers like kicking the tiger's ass more than tickling a mouse . . 'spose?
Still, when you build a bigger lifter, you just create more reciprocating mass that has to change direction at high speeds and tremendous spring pressure . . so then you have to increase valve spring pressure, stronger rockers, bigger pushrods and more expensive one piece valves . . It's kind of a vicious circle . .
All the NASCAR guys are going the other way . . Little bitty cam lobes, little flat tappet lifters, skinny pushrods, and really high rocker arm ratios, 1:8/1:9 with 125# of seat pressure . . Dunno who's right, but their engines are built to go about 550 miles, while a drag racing engine spends more time being warmed than it does racing.
I guess us drag racers like kicking the tiger's ass more than tickling a mouse . . 'spose?
