nitried or cryo

larry asa · 11-25-2008, 10:50 PM

I'am having rocker arm problems. Which has shone results?? Ideas??
Thanks Larry

Alan Roehrich · 11-25-2008, 11:02 PM

Rocker problems on what?

Bill Harris · 11-26-2008, 12:40 AM

I used to break rocker arms on my FoMoCo 429 stocker every five or six runs, always an intake (2.25" monster). Had a brand new set of NOS rockers and fulcums cyro'ed three years ago, haven't broken one since. Might also be due to increased spring pressure/shubecks/smith pushrods, but it's worth a shot. Your mileage might vary.

larry asa · 11-26-2008, 12:52 AM

Quote:

Originally Posted by Alan Roehrich

Rocker problems on what?

Chevy 427

Thanks Bill

John Musial · 11-26-2008, 09:18 AM

Larry, give Jim Bailey a call. www. finishedracing.com He will point you in the right direction.

Stick Racing · 11-26-2008, 06:47 PM

Crane Nitro Carb rockers cryo'ed.

They have worked very well for me. It's a good idea to run them for 3-400 runs and recycle them. Much like all valve train pieces, they need to be replaced after x amount of runs.

Andy Stone B/S 1102 SS/C 1112

Jim Bailey · 11-27-2008, 10:33 AM

Larry, call Wes McCracken, John Musial, Charlie Weber, Charlie Downing, Chuck Beach, Bob Marshall, Brian Seibenick and see what they have to say. OR save some time and just give me a call. Keep in mind, nitried is a surface treatment. Cryo treats the entire part. Also, not all Cryogenic Processing is created equal. 330-858-1842. JB.

Alan Roehrich · 11-27-2008, 10:54 AM

Quote:

Originally Posted by larry asa

Chevy 427

Thanks Bill

Larry,
We run the stuff from Clark Holroyd, and have since 2006. We bought a complete setup, and have not broken a single rocker since. We are going to finally break down and put a new set of rockers on this Winter. I'm running 265# on the seat, and 550# open pressure. We turn as much as 7800 RPM, and make probably 100-150 passes a year, plus dyno time. Clark's stuff is just plain GM.

Are you fully deburring your rockers?

Where are they breaking?

Jim Bailey · 11-27-2008, 11:11 AM

Alan, I've done several sets of Clark's Rockers. They are by far the nicest "stock" rockers that I've seen. Now, send me just one of your rockers. I'll treat it and provide you with a sample to try. It's on the house, what da you have to lose .JB

Kevin Cradduck · 11-27-2008, 12:36 PM

Jim,

Wouldn't the ultimate solution be to deburr (especially the oil hole), cryo, then shot peen to impart compressive stress? Deburring removes stress risers and small tears. Cryo will stress relieve and improve grain structure. Shot peening will leave the entire outside surface in compression. Nothing fails in compression.

Am I thinking correctly?

Thanks

11-25-2008, 10:50 PM	#1
larry asa Junior Member Join Date: Jul 2007 Posts: 23 Likes: 0 Liked 0 Times in 0 Posts	nitried or cryo I'am having rocker arm problems. Which has shone results?? Ideas?? Thanks Larry

11-25-2008, 11:02 PM	#2
Alan Roehrich VIP Member Join Date: May 2006 Location: Murfreesboro TN Posts: 4,915 Likes: 996 Liked 1,044 Times in 274 Posts	Re: nitried or cryo Rocker problems on what? __________________ Alan Roehrich 212A G/S

11-26-2008, 12:40 AM	#3
Bill Harris Member Join Date: Mar 2002 Location: Ooltewah, TN Posts: 420 Likes: 13 Liked 26 Times in 13 Posts	Re: nitried or cryo I used to break rocker arms on my FoMoCo 429 stocker every five or six runs, always an intake (2.25" monster). Had a brand new set of NOS rockers and fulcums cyro'ed three years ago, haven't broken one since. Might also be due to increased spring pressure/shubecks/smith pushrods, but it's worth a shot. Your mileage might vary. __________________ Bill Harris ex 2172 STK ex 2272 S/S

11-26-2008, 09:18 AM	#5
John Musial Junior Member Join Date: Dec 2005 Location: Comfort Texas Posts: 92 Likes: 63 Liked 51 Times in 3 Posts	Re: nitried or cryo Larry, give Jim Bailey a call. www. finishedracing.com He will point you in the right direction.

11-26-2008, 06:47 PM	#6
Stick Racing Member Join Date: Mar 2007 Posts: 169 Likes: 4 Liked 0 Times in 0 Posts	Re: nitried or cryo Crane Nitro Carb rockers cryo'ed. They have worked very well for me. It's a good idea to run them for 3-400 runs and recycle them. Much like all valve train pieces, they need to be replaced after x amount of runs. Andy Stone B/S 1102 SS/C 1112

11-27-2008, 10:33 AM	#7
Jim Bailey Senior Member Join Date: Aug 2004 Posts: 699 Likes: 17 Liked 571 Times in 107 Posts	Re: nitried or cryo Larry, call Wes McCracken, John Musial, Charlie Weber, Charlie Downing, Chuck Beach, Bob Marshall, Brian Seibenick and see what they have to say. OR save some time and just give me a call. Keep in mind, nitried is a surface treatment. Cryo treats the entire part. Also, not all Cryogenic Processing is created equal. 330-858-1842. JB.

11-27-2008, 11:11 AM	#9
Jim Bailey Senior Member Join Date: Aug 2004 Posts: 699 Likes: 17 Liked 571 Times in 107 Posts	Re: nitried or cryo Alan, I've done several sets of Clark's Rockers. They are by far the nicest "stock" rockers that I've seen. Now, send me just one of your rockers. I'll treat it and provide you with a sample to try. It's on the house, what da you have to lose .JB

11-27-2008, 12:36 PM	#10
Kevin Cradduck Member Join Date: May 2007 Posts: 123 Likes: 0 Liked 0 Times in 0 Posts	Re: nitried or cryo Jim, Wouldn't the ultimate solution be to deburr (especially the oil hole), cryo, then shot peen to impart compressive stress? Deburring removes stress risers and small tears. Cryo will stress relieve and improve grain structure. Shot peening will leave the entire outside surface in compression. Nothing fails in compression. Am I thinking correctly? Thanks