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Paul
Crazy Horse

USA
776 Posts

Posted - 11 Sep 2012 :  10:48:42 AM  Show Profile  Reply with Quote
I have a set of 5140 RPM connecting rods with 7/16 ARP bolts.They are going in my Pontiac 455, if I recall the torque spec for these are 75 ft lbs, is that what you guys torque Yours at?
Thank You,

Paul

PontiacMatt
Many Ponies

USA
1410 Posts

Posted - 11 Sep 2012 :  11:06:20 AM  Show Profile  Reply with Quote
I'm running the same rods I believe, thought the box had a little instruction sheet on what to torque them too, but don't remember exactly, it's been a few months...

75 ft. lbs. sounds right. again, best make sure from a professional. could also call the vendor you purchased them through and check for certain. I know Butler sells them, and they have always had great customer service in my experiences.

*72' Pontiac Lemans* - Work in Progress
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Paul
Crazy Horse

USA
776 Posts

Posted - 11 Sep 2012 :  4:03:33 PM  Show Profile  Reply with Quote
I found the paper that came with the rods, it says 70lbs for 7/16 stauds.

Paul
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PontiacMatt
Many Ponies

USA
1410 Posts

Posted - 12 Sep 2012 :  11:08:48 AM  Show Profile  Reply with Quote
good deal, always best to know for sure, and to go with Manufacturers specs/recommendations.

*72' Pontiac Lemans* - Work in Progress
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Paul
Crazy Horse

USA
776 Posts

Posted - 12 Sep 2012 :  11:45:41 AM  Show Profile  Reply with Quote
Thanks,
The Machinist who installed the pistons and balanced all the parts hid it in the box.

Paul
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beertracker
Cochise

427 Posts

Posted - 28 Nov 2017 :  12:38:10 PM  Show Profile  Reply with Quote
My search lead me to this post. Does any one know how many revolutions per minute you can safely spin a Race Products Maximum 5140 rod? The engine is a mild (415 hp) 455. I called Race Products Maximum and they said good to 550 hp and we don't have a revolutions per minute
specification.

Thanks,
bt

Edited by - beertracker on 28 Nov 2017 12:43:16 PM
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cortcomp
Coyote

USA
5463 Posts

Posted - 28 Nov 2017 :  7:59:01 PM  Show Profile  Visit cortcomp's Homepage  Reply with Quote
IIRC, Mr. Pbody told me not to swing them more than 5500 regularly, and probably about 6k here and there, in the 455 i put together. On a 455 Jim Taylor put together, with reconditioned stock rods, it is written on the paper and underlined twice that the redline is 5200. Take that second hand info for what it's worth i guess.
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beertracker
Cochise

427 Posts

Posted - 30 Nov 2017 :  10:05:16 AM  Show Profile  Reply with Quote
cortcomp, thanks for the info. bt
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beertracker
Cochise

427 Posts

Posted - 24 Apr 2019 :  10:02:35 PM  Show Profile  Reply with Quote
I just talked to Butler and their RPM 5140 Forged I Beam Rod, 6.625", 2.250" Pontiac RJ torques to 75 lb ft. However if you look at the RPM instruction sheet that came with their LG5-6625I OEM, forged 5140 rod it shows 7/16" ARP 8740 60 lb ft and 7/16" WAVE 8740 75 lb ft. What is WAVE?

So whose numbers do you believe? I don't know but this is the first and last time I use RPM products in my build. I wish RPM would get their act together. I tried emailing these people and they don't answer.

bt
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Corncob2061
Cochise

USA
453 Posts

Posted - 26 Apr 2019 :  09:32:00 AM  Show Profile  Reply with Quote
I know you have got this figure out bt. But for others that do a search. Wave loc is ARPs rod bolts that have spiral protrusions that jam themselves in the rod bolt hole for better cap alignment. The extra torque helps make sure the bolts are seated right and gives them a little more clamping force. Jay
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beertracker
Cochise

427 Posts

Posted - 29 Apr 2019 :  3:33:33 PM  Show Profile  Reply with Quote
Another reason not to use RPM rods. While checking side to side clearance rod caps 3 and 4 are touching; zero clearance. I should have knew something was wrong when installing cap #3 I had to tap it in place lightly with a rubber hammer. The rotating assembly has already been balanced so I hope I don't have to file the part to fit. My concern is removing metal so I have to redo the balance?

Rod 4 and it's cap fit on the crank throw fine. Rod 3 fit ok also but when I put in cap 3 I noticed the interference.

The big chamfer side of the rod is facing the crank fillet just like it's supposed to be. Piston arrows are point to front of engine.

bt
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Corncob2061
Cochise

USA
453 Posts

Posted - 30 Apr 2019 :  09:07:06 AM  Show Profile  Reply with Quote
Could measure the side clearance on the other throws, and look and see if any have a wider clearance. Maybe 3 or 4 would work better over on another throw.
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tjs44
Crazy Horse

USA
604 Posts

Posted - 30 Apr 2019 :  1:31:46 PM  Show Profile  Reply with Quote
Make sure you have the N bearings!I had a issue on one engine I had built,too little side clearance because the builder did not use the N bearings.Tom
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beertracker
Cochise

427 Posts

Posted - 30 Apr 2019 :  9:19:54 PM  Show Profile  Reply with Quote
I will try the suggestions. I am using Clevite CB-758HN-10 rod bearings so I am ok with N bearings. I am using a Pontiac crank cut .010"\.010".
bt

Edited by - beertracker on 01 May 2019 12:49:57 AM
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Corncob2061
Cochise

USA
453 Posts

Posted - 30 Apr 2019 :  11:24:05 PM  Show Profile  Reply with Quote
IRC, the N bearings end the part number with the letter N. They are used for large fillet journals, aftermarket cranks, or cranks that are cut down such Pontic journal turned down to a big block Chevy journal. I believe that is what Tom is talking about. When you try to use standard width bearings the larger fillets in the crank shove the rods together and loose all the side clearance between the rods..I assume your 455 has a factory 455 crank in it. If it is a aftermarket nodular or forged crank you have to run the N bearings, and you can run the N in stock engines, but you should need to. If you have a factory crank, I suspect one or both of the rods are machined to wide.

What are the side clearances on some other the other journals? Are they all tight? Jay

Edited by - Corncob2061 on 30 Apr 2019 11:26:21 PM
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