ARP main studs question (for my 489 build) - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 04-26-2011, 03:58 AM
Registered User
 
Last photo:
Join Date: Jan 2010
Location: Guatemala, Central America
Posts: 10
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
ARP main studs question (for my 489 build)

Hello everyone!

I'm building a stroker 489 torque monster for my 4x4 79 Blazer.

So I got new ARP main studs for it. During the machining process, I got the mains align honed. Then the caps were ground down to get the right clearance for the crankshaft. The thing is that they had to replace and retorque the caps about 5-6 times during the process. I still have to do the final assembly after cleaning it, so that's one more torque down for the studs. I've read somewhere that ARP bolts stretch permanently and shouldn't be used more than 5 times. Can I still use these studs? Or am I risking something getting damaged in the long run due to an incorrect torque reading?

Thanks!

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 04-26-2011, 09:17 PM
richard stewart 3rd's Avatar
Registered User
 

Last journal entry: 351W rebuild
Last photo:
Join Date: Jan 2006
Location: tremont, pa.
Age: 70
Posts: 2,218
Wiki Edits: 0

Thanks: 14
Thanked 15 Times in 14 Posts
Hi
I've never heard of a stud being unusable after five torque downs, the number of times it's torqued isn't the deciding factor on weather it should or shouldn't be used. Heck you can over stretch it on the first torquing. The correct way is to measure it.

If you measure a fastener and it is 0.0005˝ longer than its original length, it has been compromised and must be replaced.
Rich
PS Call ARP they'll tell you the same thing.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 04-26-2011, 11:54 PM
Registered User
 
Last photo:
Join Date: Jan 2010
Location: Guatemala, Central America
Posts: 10
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Thanks for the good news Richard. What about ARP rod bolts. Are those more prone to failure?
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 04-27-2011, 06:47 AM
Irelands child's Avatar
Registered User
 
Last wiki edit: Ford engine specifications Last photo:
Join Date: Jan 2005
Location: Upstate New York
Posts: 4,913
Wiki Edits: 8

Thanks: 14
Thanked 205 Times in 186 Posts
Some of the newer cars have single use bolting, I know Ford with their modular engines specifies some bolts be replaced, which is probably where that kind of information originated. I agree with Richard - and especially since there has not been any heat cycling of these fasteners.

Dave W
__________________
Irelands child
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 04-27-2011, 07:19 AM
Registered User
 
Last photo:
Join Date: Nov 2009
Location: Austria
Posts: 85
Wiki Edits: 0

Thanks: 4
Thanked 0 Times in 0 Posts
Bolts only need to be discarded after use if they are of the torque to yield type. And even then, most headbolts can be reused once or even twice depending on how they are being torqued down. I don't know about studs though which is the specific topic here, so i'm subscribed for more replies but seems Richard already nailed it
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 04-27-2011, 10:54 AM
cobalt327's Avatar
WFO
 
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Location: Atlanta
Age: 59
Posts: 5,037
Wiki Edits: 1616

Thanks: 128
Thanked 597 Times in 546 Posts
Quote:
Originally Posted by Blazer79
Hello everyone!

I'm building a stroker 489 torque monster for my 4x4 79 Blazer.

So I got new ARP main studs for it. During the machining process, I got the mains align honed. Then the caps were ground down to get the right clearance for the crankshaft. The thing is that they had to replace and retorque the caps about 5-6 times during the process. I still have to do the final assembly after cleaning it, so that's one more torque down for the studs. I've read somewhere that ARP bolts stretch permanently and shouldn't be used more than 5 times. Can I still use these studs? Or am I risking something getting damaged in the long run due to an incorrect torque reading?

Thanks!
Actually, repeated tightening and loosening cycles will burnish the threads and in the end will give a more accurate reading than would fresh, one-time-tightened fasteners.

From a '98 ARP catalog:
Quote:
The friction factor changes from one application to the next. That is, the friction is at its highest value when the fastener is first tightened. Each additional time the fastener is torqued and loosened, this value gets smaller. Eventually the friction levels out and becomes constant for all following repetitions. Therefore, new fasteners should be tightened and loosened through several cycles before applying final torque. The number of times depends on the lubricant. For all situations where ARP lubricants are used, five cycles are required before final torquing.
This may have been supreceded, but I believe they still call for cycling the fasteners through a couple tight-loose cycles.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 04-27-2011, 11:31 AM
richard stewart 3rd's Avatar
Registered User
 

Last journal entry: 351W rebuild
Last photo:
Join Date: Jan 2006
Location: tremont, pa.
Age: 70
Posts: 2,218
Wiki Edits: 0

Thanks: 14
Thanked 15 Times in 14 Posts
Hi
Any fastener in that environment (Rod Bolts, mains, etc.) are subject to failure, all you can do is try & make it as bullet proof as possible.
This is don by using the best parts your able to afford & close attention to detail.
Well ARP has been at this for awhile (1968) & are considered the best of the bunch. Back when I started & I'm sure a lot of the older men remember when it was a crap shoot as to weather the thing was going to stay together, the quality wasn't there in the fasteners, many engines failed due to the fasteners inability to handle the stress. Today it's much different, now when I put an engine together I no longer worry about the fasteners not being up to the task. I use ARP fasteners exclusivity.
Rich
PS Normally when you see an advertizement for connecting rods, you'll read "rods have been upgraded to ARP fasteners/bolts"

X2 with the cycling of the fasteners.

Last edited by richard stewart 3rd; 04-27-2011 at 11:36 AM.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
main cap studs garand wizard Engine 4 12-12-2010 11:57 AM
Main studs too short BringBackTheCamaro Engine 3 02-26-2006 03:16 PM
Main Studs Not Long Enough Canadian Charlie Engine 5 02-09-2006 11:25 AM
ARP Main Studs Kit Canadian Charlie Engine 7 02-05-2006 04:45 AM
Need Advice On The Use Of Main And Head Studs GoneNova/406 Engine 16 01-19-2005 05:15 PM


All times are GMT -6. The time now is 01:15 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.