Re: Speedmaster DNA rocker arms
[Re: fourgearsavoy]
#3076687
09/12/22 07:14 PM
09/12/22 07:14 PM
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Joined: Feb 2005
Posts: 20,173 PA.
pittsburghracer
"Little"John
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"Little"John
Joined: Feb 2005
Posts: 20,173
PA.
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This is what I say about Chinese roller bearing rockers https://youtu.be/A732Cuuo2tI
1970 Duster Edelbrock headed 408 5.984@112.52 422 Indy headed small block 5.982@112.56 mph 9.42@138.27
Livin and lovin life one day at a time
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Re: Speedmaster DNA rocker arms
[Re: fourgearsavoy]
#3076805
09/13/22 07:32 AM
09/13/22 07:32 AM
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Joined: Dec 2021
Posts: 1,126 Loudoun County, VA
Brad_Haak
super stock
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super stock
Joined: Dec 2021
Posts: 1,126
Loudoun County, VA
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Yes, they LOOK nicer than they used to... but if it's the same quality of materials as before -->
2021 Challenger 6.4L Scat Pack 1320 100% stock: 1.680, 11.894 at 113.75 (DA 175 ft) weight reduction, wheels, tires, Hellcat air box: 1.661, 11.686 at 115.97 (DA 710 ft)
1973 Challenger 452 ci street/strip [2008] pump gas, DOT radials: 1.454, 10.523 at 126.44 (DA 514 ft)
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Re: Speedmaster DNA rocker arms
[Re: Brad_Haak]
#3077083
09/13/22 10:52 PM
09/13/22 10:52 PM
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Joined: Jul 2006
Posts: 4,319 Puyallup, WA
StealthWedge67
master
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master
Joined: Jul 2006
Posts: 4,319
Puyallup, WA
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I’m using them. After having good luck for years with a set of their bushed Stainless rockers, I decided to give the DNA rockers a chance. I found the same exact thing as I had with the steel set, and that is that the adjuster hardware is junk. When I first installed them, I found the lash increasing and upon inspection the ball ends on the adjuster studs were wearing down ridiculously fast. Like visible wear in 10 minutes run time. I called Speedmaster / Procomp and to their credit, they did work with me and were willing to own the issue. I bought some name brand (comp if I remember correctly) adjuster hardware, and installed it. I’ve no problems with them since. Been 4 years on a solid flat tappet and they have been near perfect with respect to lash checks. I’m about to run them on my new engine which will feature a solid roller with 600 lbs of open pressure.
Picture is of the junk adjuster studs after 1 warm up. Zero wear or issue with my Manton pushrod cups, but balls were going away fast!
Last edited by StealthWedge67; 09/13/22 10:53 PM.
LemonWedge - Street heavy / Strip ready - 11.07 @ 120
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Re: Speedmaster DNA rocker arms
[Re: StealthWedge67]
#3077150
09/14/22 09:16 AM
09/14/22 09:16 AM
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Joined: Dec 2021
Posts: 1,126 Loudoun County, VA
Brad_Haak
super stock
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super stock
Joined: Dec 2021
Posts: 1,126
Loudoun County, VA
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StealthWedge67 - Have you disassembled them after long-term usage to inspect the shaft for wear, the bearings for freedom of movement, etc.? 600 lbs open pressure...
2021 Challenger 6.4L Scat Pack 1320 100% stock: 1.680, 11.894 at 113.75 (DA 175 ft) weight reduction, wheels, tires, Hellcat air box: 1.661, 11.686 at 115.97 (DA 710 ft)
1973 Challenger 452 ci street/strip [2008] pump gas, DOT radials: 1.454, 10.523 at 126.44 (DA 514 ft)
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Re: Speedmaster DNA rocker arms
[Re: fourgearsavoy]
#3077211
09/14/22 01:22 PM
09/14/22 01:22 PM
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Joined: Oct 2007
Posts: 4,206 New York
polyspheric
master
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master
Joined: Oct 2007
Posts: 4,206
New York
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Those tip rollers look small, or is it just my failing eyesight? If yes, they oscillate over a greater range than "normal" rollers, which means more needles are loaded*. Bad: has fewer rollers.
* The roller arc (degrees of rotation before reversal) is a function of its diameter and net lift. 10" rollers will move 1 degree with .500" lift, and the entire load will land on a few needles at 12 o'clock position.
Needles where you don't need them make me nervous. Ever seen a Harley that lost a lifter? The loose needles get between the cam gear teeth, which blows the right case into junk.
Boffin Emeritus
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Re: Speedmaster DNA rocker arms
[Re: polyspheric]
#3077225
09/14/22 01:50 PM
09/14/22 01:50 PM
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Joined: Jun 2003
Posts: 182 Suburb of Chicago, IL
BCFKody
member
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member
Joined: Jun 2003
Posts: 182
Suburb of Chicago, IL
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Unlike all the other Chinesium aluminum roller rockers, there are no needles bearings on the DNA rockers, they ride on bronze bushings.
Last edited by BCFKody; 09/14/22 01:50 PM.
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Re: Speedmaster DNA rocker arms
[Re: BCFKody]
#3077235
09/14/22 02:26 PM
09/14/22 02:26 PM
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Joined: Jan 2003
Posts: 4,720 Moved to N.E. Tennessee
GomangoCuda
master
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master
Joined: Jan 2003
Posts: 4,720
Moved to N.E. Tennessee
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Unlike all the other Chinesium aluminum roller rockers, there are no needles bearings on the DNA rockers, they ride on bronze bushings. Really?
In theory, there is no difference between theory and practice. In practice, there is.
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Re: Speedmaster DNA rocker arms
[Re: GomangoCuda]
#3077239
09/14/22 02:30 PM
09/14/22 02:30 PM
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Joined: Feb 2005
Posts: 20,173 PA.
pittsburghracer
"Little"John
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"Little"John
Joined: Feb 2005
Posts: 20,173
PA.
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Unlike all the other Chinesium aluminum roller rockers, there are no needles bearings on the DNA rockers, they ride on bronze bushings. Really? He had me double checking myself too. Hmmmm
1970 Duster Edelbrock headed 408 5.984@112.52 422 Indy headed small block 5.982@112.56 mph 9.42@138.27
Livin and lovin life one day at a time
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Re: Speedmaster DNA rocker arms
[Re: BCFKody]
#3077264
09/14/22 04:59 PM
09/14/22 04:59 PM
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Joined: Oct 2006
Posts: 1,264 New York, USA
Chargerfan68
pro stock
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pro stock
Joined: Oct 2006
Posts: 1,264
New York, USA
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Cannot argue with that…..are there 2 options?
1.50 60Ft. , 10.75@ 127MPH Hauling 3900 LBS.
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Re: Speedmaster DNA rocker arms
[Re: pittsburghracer]
#3077293
09/14/22 07:44 PM
09/14/22 07:44 PM
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Joined: Dec 2004
Posts: 10,553 Rittman Ohio
fourgearsavoy
OP
I Live Here
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OP
I Live Here
Joined: Dec 2004
Posts: 10,553
Rittman Ohio
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That bushing deal makes me very happy Put some premium hardware in them and they will be fine with 430 on the nose. Gus
64 Plymouth Savoy 493 Indy EZ's by Nick at Compu-Flow 5-Speed Richmond faceplate Liberty box Dana 60
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