#1  
Old 09-11-2025, 11:50 AM
hurryinhoosier62 hurryinhoosier62 is offline
Ultimate Warrior
 
Join Date: May 2006
Location: Floyd Co., IN/SE KY
Posts: 4,075
Default

Quote:
Originally Posted by scott70 View Post
I actually found some pics from like 6 years ago when the engine was apart . I don’t see any markings on the rods but in one pic I can see arp on the bolt head. Should be ok for what I do? Obviously they’ve hung in there since 2012 but I was just thinking if it really should have a better rod? Maybe not? I just don’t know what they really are as far as quality.
Those resemble the 5140 alloy rods Ace sold. He also sold 4340 rods but they were “H” beams. As many have already said, replace the bolts and have the rods reconditioned. I would add to have the rods magnafluxed as well.

__________________
“It takes considerable knowledge just to realize the extent of your own ignorance.”

Dr. Thomas Sowell
  #2  
Old 09-11-2025, 12:01 PM
scott70's Avatar
scott70 scott70 is offline
Ultimate Warrior
 
Join Date: May 2002
Location: maine
Posts: 2,733
Default

Quote:
Originally Posted by hurryinhoosier62 View Post
Those resemble the 5140 alloy rods Ace sold. He also sold 4340 rods but they were “H” beams. As many have already said, replace the bolts and have the rods reconditioned. I would add to have the rods magnafluxed as well.
These are probably the 5140 then. I do remember 2 different numbers, those are probably it. Replace the current arp bolts?

__________________
72 lemans,455 e-head, UD 255/263 solid flat,3.73 gears,,,10" 4400 converter,, 6.68 at 101.8 mph,,1.44 60 ft.2007
(cam 271/278 roller)9"CC.4.11gear 6.41 at 106.32 mph 1.42 60 ft.(2009) SOLD,SOLD
1970 GTO 455 4 speed #matching,, 3.31 posi.Stock manifolds. # 64 heads.A factory mint tuquoise ,69' judge stripe car. 8.45 @ 88.1 mph on slippery street tires.Bad 2.19 60ft.Owned since 86'
  #3  
Old 09-12-2025, 08:16 PM
hurryinhoosier62 hurryinhoosier62 is offline
Ultimate Warrior
 
Join Date: May 2006
Location: Floyd Co., IN/SE KY
Posts: 4,075
Default

Quote:
Originally Posted by scott70 View Post
These are probably the 5140 then. I do remember 2 different numbers, those are probably it. Replace the current arp bolts?
Absolutely. You have no idea IF they were installed and torqued correctly. I view new rod bolts as cheap insurance.

__________________
“It takes considerable knowledge just to realize the extent of your own ignorance.”

Dr. Thomas Sowell
  #4  
Old 09-11-2025, 09:38 PM
PunchT37's Avatar
PunchT37 PunchT37 is offline
Ultimate Warrior
 
Join Date: Dec 2002
Location: Lafayette,LA
Posts: 3,349
Default

Quote:
Originally Posted by hurryinhoosier62 View Post
Those resemble the 5140 alloy rods Ace sold. He also sold 4340 rods but they were “H” beams. As many have already said, replace the bolts and have the rods reconditioned. I would add to have the rods magnafluxed as well.
I have some 4340 I beams from Ace. Full float.
Attached Thumbnails
Click image for larger version

Name:	user143038_pic14533_1657636985.jpg
Views:	130
Size:	61.9 KB
ID:	657003  


Last edited by PunchT37; 09-11-2025 at 09:44 PM.
  #5  
Old 09-12-2025, 02:55 PM
Dragncar Dragncar is offline
Ultimate Warrior
 
Join Date: Mar 2004
Location: Humbolt County California
Posts: 9,232
Default

Quote:
Originally Posted by PunchT37 View Post
I have some 4340 I beams from Ace. Full float.
I have a set of 6.8s.
Story on those rods right from the horses mouth. One day at RPM a guy came in with a set of Crower Billet rods and asked the head guy at RPM if they could copy them. They did just that.
I wish the cap was a little beefier though. Someday I will put them to use on a milder engine. I have Molnar rods and a real set of Crower billets for heavier duty stuff.
If anyone knows where I can find a couple of Crower mid weightish BBC 6.8s let me know.

  #6  
Old 09-12-2025, 08:28 PM
hurryinhoosier62 hurryinhoosier62 is offline
Ultimate Warrior
 
Join Date: May 2006
Location: Floyd Co., IN/SE KY
Posts: 4,075
Default

Quote:
Originally Posted by PunchT37 View Post
I have some 4340 I beams from Ace. Full float.
Nearly all the 4340 rods I have seen that were sold by Ace were “H” beams, but I do recall RPM International ( Ace’s source) did sell an “ultra light” 4340 “I” beam rod.

__________________
“It takes considerable knowledge just to realize the extent of your own ignorance.”

Dr. Thomas Sowell
The Following User Says Thank You to hurryinhoosier62 For This Useful Post:
  #7  
Old 09-12-2025, 10:15 PM
PunchT37's Avatar
PunchT37 PunchT37 is offline
Ultimate Warrior
 
Join Date: Dec 2002
Location: Lafayette,LA
Posts: 3,349
Default

Quote:
Originally Posted by hurryinhoosier62 View Post
Nearly all the 4340 rods I have seen that were sold by Ace were “H” beams, but I do recall RPM International ( Ace’s source) did sell an “ultra light” 4340 “I” beam rod.
Mine were a 740`ish gram I beam. They sold a 720`ish "A" beam shortly after.

The Following User Says Thank You to PunchT37 For This Useful Post:
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not 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

Forum Jump


All times are GMT -4. The time now is 06:49 PM.

 

About Us

The PY Online Forums is the largest online gathering of Pontiac enthusiasts anywhere in the world. Founded in 1991, it was also the first online forum for people to gather and talk about their Pontiacs. Since then, it has become the mecca of Pontiac technical data and knowledge that no other place can surpass.

 




Copyright © 2017