Re: Would pushrod length make this much difference?
[Re: madscientist]
#2449215
02/09/18 07:53 PM
02/09/18 07:53 PM
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Joined: Jan 2003
Posts: 15,439 Val-haul-ass... eventually
BradH
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Taking time off to work on my car
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OP
Taking time off to work on my car
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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I wonder if these instructions apply to stud mounted rockers only? Nope. Adjuster position affects geometry on stud and shaft rockers. Adjuster position on a shaft system has no effect on geometry; that's determined by the rocker fulcrum location with respect to the valve.
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Re: Would pushrod length make this much difference?
[Re: BradH]
#2449253
02/09/18 09:19 PM
02/09/18 09:19 PM
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Joined: Jun 2003
Posts: 9,225 Charleston
sixpackgut
Drag Week Mod Champion
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Drag Week Mod Champion
Joined: Jun 2003
Posts: 9,225
Charleston
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Geez, and I'm just happy when the pushrods stay where they belong
Gen 3 power 6.22@110, 9.85@135 Follow @g3hemiswap on instagram
performance only racing, CRT, ultimate converter, superior design concepts, ThumperCarbs
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Re: Would pushrod length make this much difference?
[Re: AndyF]
#2451869
02/14/18 10:11 PM
02/14/18 10:11 PM
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Joined: Oct 2011
Posts: 3,036 bean town ....Ca
WHITEDART
master
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master
Joined: Oct 2011
Posts: 3,036
bean town ....Ca
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Pushrod length was one of the things we explored when I went to competition engine building school.. by adding .050 a pushrod length we gained about .06 at Max lift.But the early and mid numbers suffered slightly... made absolutely no difference on back-to-back on the dyno.. I would say picking a pushrod length with the adjuster set and it's recommended location would be your best bet
In the 8s N/A.with Brett miller W8's 5.07 at 133 at 2700lb
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Re: Would pushrod length make this much difference?
[Re: AndyF]
#2452179
02/15/18 04:03 PM
02/15/18 04:03 PM
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Joined: Jan 2003
Posts: 15,439 Val-haul-ass... eventually
BradH
OP
Taking time off to work on my car
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OP
Taking time off to work on my car
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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You aren't an idiot, you just haven't learned everything the hard way yet. Once you learn everything the hard way you'll be a bitter, grumpy old man with no patience for whipersnappers who haven't learned everything yet. 1. I've told my friends & family for years, I learn EVERYTHING the hard way. 2. I'm already a bitter & grumpy old man with no patience for others... and I still don't know sh!t.
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Re: Would pushrod length make this much difference?
[Re: Cab_Burge]
#2452546
02/16/18 02:11 PM
02/16/18 02:11 PM
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Joined: Jan 2003
Posts: 15,439 Val-haul-ass... eventually
BradH
OP
Taking time off to work on my car
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OP
Taking time off to work on my car
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Val-haul-ass... eventually
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...actual valve lift at the retainers with the race valve springs will never be as much as the advertised valve lift...
That's entirely dependent upon how the rocker arm is designed. AndyF's rocker arm articles touched on how some of the brands he checked were "over-ratioed" w/ checking springs, but came in at or above the advertised ratio when checked w/ the actual valve springs. As far as deflection, I believe it can be in the pushrods, the rocker bodies, and/or the shafts, depending upon the components used. Not sure Joe Average's budget can eliminate it entirely, but I've seen some cases where it certainly went beyond my idea of an "acceptable" amount in terms of lift/ratio loss.
Last edited by BradH; 02/16/18 02:12 PM.
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Re: Would pushrod length make this much difference?
[Re: BradH]
#2452890
02/17/18 01:15 AM
02/17/18 01:15 AM
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Joined: May 2017
Posts: 73 WI
Brewzer67
member
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member
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WI
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Oh, I came across some pics of "stuff" that Mike at B3RE did w/ some Hughes rockers used on Trick Flow heads that included switching to cup-style adjusters (requires pushrod oiling). I can't say exactly what differences would result from such a mod, but it's pretty obvious the pushrod tip's relation to the rocker fulcrum would change big-time.
I'm curious where you found these pictures. These look like my heads and rockers. They came out great with Mike's kit and the change to cup adjusters. The sweep is small and centered and there is minimal lift loss. I am running dual taper 9/16" (.165 wall) oil thru pushrods from Trend and lose less than .008 lift on a .716 lift solid roller. With the change to the cup adjusters there is almost no change in pushrod angle from full closed to full open. Even though the pushrod side doesn't add too much in the way of harmonics issues, I can't help but think this minimal movement goes a long way to promoting valve train stability.
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