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Limitations of stock rockers/rocker shaft in performance aps #1812379 04/26/15 04:39 PM 04/26/15 04:39 PM
Joined: Jun 2013 Posts: 1,521 Tacoma, Washington USA A Adam71Charger OP pro stock
Adam71Charger OP pro stock A Joined: Jun 2013 Posts: 1,521 Tacoma, Washington USA	What are the limitations of the stock rocker shafts/arms? RPM limits, Lift limits?

Re: Limitations of stock rockers/rocker shaft in performance aps [Re: Adam71Charger] #1812425 04/26/15 06:15 PM 04/26/15 06:15 PM
Joined: Nov 2006 Posts: 1,456 oklahoma F forphorty pro stock
forphorty pro stock F Joined: Nov 2006 Posts: 1,456 oklahoma	440 292 .501 Comp Magnum 5800 rpm shift point. owned for 20 + years , driven often. Stock stamped rockers. One rocker failure about 15 years ago. The holes do elongate over time though. They may not look like much,But I definitely have more faith in them than an entry level(cheap) roller rocker.

Re: Limitations of stock rockers/rocker shaft in performance aps [Re: Adam71Charger] #1812475 04/26/15 07:14 PM 04/26/15 07:14 PM
Joined: Sep 2007 Posts: 14,889 up yours Supercuda About to go away
Supercuda About to go away Joined: Sep 2007 Posts: 14,889 up yours	Depends on exactly which "stock" rocker setup you are referring to. LA adjustable ones? LA stamped? B/RB stamped? early or late style? B/RB adjustables? They say there are no such thing as a stupid question. They say there is always the exception that proves the rule. Don't be the exception.

Re: Limitations of stock rockers/rocker shaft in performance aps [Re: Supercuda] #1812654 04/26/15 11:22 PM 04/26/15 11:22 PM
Joined: Jun 2013 Posts: 1,521 Tacoma, Washington USA A Adam71Charger OP pro stock
Adam71Charger OP pro stock A Joined: Jun 2013 Posts: 1,521 Tacoma, Washington USA	Stamped from 1977 452 heads. Thinking about using the heads on a basic rebuild engine.

Re: Limitations of stock rockers/rocker shaft in performance aps [Re: Adam71Charger] #1812684 04/26/15 11:43 PM 04/26/15 11:43 PM
Joined: Jan 2007 Posts: 7,664 IN A ahy master
ahy master A Joined: Jan 2007 Posts: 7,664 IN	Rule of thumb, .5" lift. They have been used with 509 cams successfully but can fail with heavy springs/frequent high RPM in that application (>6000 RPM?).

Re: Limitations of stock rockers/rocker shaft in performance aps [Re: Adam71Charger] #1812685 04/26/15 11:43 PM 04/26/15 11:43 PM
Joined: Jul 2003 Posts: 3,376 Rancho Cordova, CA Exit1965 master
Exit1965 master Joined: Jul 2003 Posts: 3,376 Rancho Cordova, CA	I remember some online Mopar magazine article where they used stamped rockers (probably aftermarket HD versions) on a cam around .530 lift. I have used the HD variety for years with a .509 cam and eddy heads and springs. No problems at all, not that I put a lot of miles on it, but I don't think I'm pushing the limits with them either.

Re: Limitations of stock rockers/rocker shaft in performance aps [Re: Adam71Charger] #1812898 04/27/15 09:53 AM 04/27/15 09:53 AM
Joined: Jan 2003 Posts: 1,643 A certified culture free zone. 74RALLYE top fuel
74RALLYE top fuel Joined: Jan 2003 Posts: 1,643 A certified culture free zone.	I've had 2 Harland Sharp roller tip rockers fail on a professionally built street engine. I'm not exceeding 500hp, so the next 440 get stock rockers.

Re: Limitations of stock rockers/rocker shaft in performance aps [Re: Adam71Charger] #1812963 04/27/15 12:22 PM 04/27/15 12:22 PM
Joined: Sep 2007 Posts: 14,889 up yours Supercuda About to go away
Supercuda About to go away Joined: Sep 2007 Posts: 14,889 up yours	Early B/RB stamped units where known to put a pushrod thru the cup in spirited use, so Chrysler stepped up to a thicker metal to fix it. 77's should be that thicker stuff. I believe all the aftermarket stuff available today is also the thicker stuff. They say there are no such thing as a stupid question. They say there is always the exception that proves the rule. Don't be the exception.

Re: Limitations of stock rockers/rocker shaft in performance aps [Re: Adam71Charger] #1813095 04/27/15 03:26 PM 04/27/15 03:26 PM
Joined: Jan 2003 Posts: 30,994 Oregon A AndyF I Win
AndyF I Win A Joined: Jan 2003 Posts: 30,994 Oregon	Yeah, a pushrod will poke thru the stamped rocker arms pretty quickly once the spring pressure gets much above stock levels. I've seen it happen a few times on "budget" engines. My old 1 ton truck came home on a flatbed once after a rocker arm failed in the 440. That engine had a very mild 440+6 cam in it with stock type springs.

Re: Limitations of stock rockers/rocker shaft in performance aps [Re: Adam71Charger] #1813423 04/27/15 10:15 PM 04/27/15 10:15 PM
Joined: Sep 2007 Posts: 14,889 up yours Supercuda About to go away
Supercuda About to go away Joined: Sep 2007 Posts: 14,889 up yours	I ran a street hemi grind in my 413 with stock stamped rockers and the proper springs with zero issues. YMMV, but I know I had the later and thicker ones. Never put a came with .500" or more lift in my engines anyway. They say there are no such thing as a stupid question. They say there is always the exception that proves the rule. Don't be the exception.

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