ARP 425's who has the right way to install?

KILLER 'B' said:
In the instructions just posted it reads, "Thread studs in to block SNUG, DO NOT TORQUE STUDS IN BLOCK".

Snug would mean bottomed out, would it not?



:clap: Now please explain how a 1.75 thread will turn on the far end of the stud when you have a 1.25 thread pitch on the nut you're turning? The only way the stud will turn while you are torquing, is if the threads are boogered up on either the nut and/or top of stud OR if there is not enough lubrication.. When we do a FIRE RING re-torque, we go as far as loosening and re-lubing one at a time through the whole sequence. I was able to get 1/4 turn out of each nut for 3 re-torques. On the forth they clearly stopped moving, so we didn't bother to go any further. I have put studs on a stock gasket before. I torqued all 26 studs. Then after I was done, I went ahead and double checked that they were all torqued to the proper specifiaction and that none of them felt funny. I removed one nut, re-lubed, re installed the nut, and re-torqued. IT DID NOT MOVE Out of all the engines I have rebuilt and seen rebuilt, I or any one else, have not ever gone and told the customer that, "Hey, in a thousand hours or so, I should come back and make sure your head bolts are tight...."
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I can't explain why, all I can say is I have seen it on both my truck as well as when I was helping Mork with his truck. Oil on the bottom, ARP lube on top. Either way, it happened. Thats also the procedure we use on the studs at work, so thats the reason I do it the way I do.
 
anyone have the bolt pattern sequence for the studs? like how to do it from the factory?
there is so many different ways.

when retorquing the motor should be cold right?

i think i will run them into block just hand tight using motor oil on the threads and the arp lube up top on the nuts washer and threads. go to 90 ft lbs 110 and then 125 get the truck hot a couple times and retorque them cold correct. sound like a good idea?
 
1985cucv said:
anyone have the bolt pattern sequence for the studs? like how to do it from the factory?
there is so many different ways.

when retorquing the motor should be cold right?

i think i will run them into block just hand tight using motor oil on the threads and the arp lube up top on the nuts washer and threads. go to 90 ft lbs 110 and then 125 get the truck hot a couple times and retorque them cold correct. sound like a good idea?
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re-torque cold.. id do 50-75-100-125.. then double check...

pattern is simple. circular pattern from center of head outward..
Torque20Sequence.jpg
 
Honestly I would just back them out slightly. But other than that your on the money
 
i made a tool... cut the head off an old bolt, then welded another head bolt to it, the cut a groove done the length of threads, and cleaned up, so i can run it down into hole with head on and it cleans all the crap out of the bottom of the hole so the stud will bottom out right... if u have head off u dont have to weld the 2 together... worked well the one time i used it.
 
I just use a tap to clean out the threads. I also bottom tap all the holes
 
morkable said:
I just use a tap to clean out the threads. I also bottom tap all the holes
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yeah but the tap i have isnt 9 inches long to get to bottom of hole with the head on... definite good stuff on the bottom tapping though
 
Why bottom tap the holes if you don't bottom the studs out? Are you looking for an argument?
 
You bottom tap so you can get more threads in the block. You dont bottom them out so it wont pull the threads out when you get them in there. It even says in the instructions for both arp and a1. I am sure that their engineers know something, I doubt that they would just put that in there to hear themselves
 
morkable said:
I am a firm believer in retorques. Your head gasket (even MLS) will crush to a certain degree. If you dont believe it, mark your studs before you do a retorque, you will gain some.
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On an existing head gasket where you replace the studs one at a time, the extra makeup is most likely from the fact that when you torque a stud you are applying a substantial load to the thread interface between the stud's threads and the nut's threads. Every time you torque, you are changing that surface's coefficient of friction. Basically you are polishing/smoothing the thread surface due to load and rotation. This is why ARP recommended multiple torque cycles (3-4 usually) with their old Moly Based Lube. I have spoke with an ARP tech guy on this. The new Ultra lube is suppose to reduce this torque scatter phenomena. They claim it hit within 5% of the desired pre-load value on the first torquing.

I did my studs one at a time and torqued up to my max torque of 140 ft-lbs (ARP 425s) in stages with the new lube. I then backed them off and re-torqued to 140 ft-lbs one at a time. They made a little more, so I was happy and called it a day. No re-torque here. When I get around to my compound setup, I plan to re-torque to 150 ft-lbs.
 
morkable said:
You bottom tap so you can get more threads in the block. You dont bottom them out so it wont pull the threads out when you get them in there. It even says in the instructions for both arp and a1. I am sure that their engineers know something, I doubt that they would just put that in there to hear themselves
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:stab:

I'm aware of why they want you to bottom tap... I'm not arguing with you on the internet, like a 12-year-old.... Good day, sir...
 
LOL no kidding. I think that there is only one 12 year old........
 
ok so take the 425s higher than 125 ft lbs ill go to 140 as well i remember someone went to like 180 testing them i want to say it was the soup nazi and they didnt stretch til like 175 or so?

so 140 is the ticket then?

and now i need a bottoming tap?
 
I had done mine to 150, but the arp tech told me that 125 130 is better. He told me that because of the tensile strength of the stud they dont stretch as easy, if you go too much they can possibly start to stretch, which then takes away everything you gained
 
So what is the point to loosen the bolt and then retorque to the next ft-lb's? I would think that you get better results if you stayed where it was at and just torqued where you last let off, please inform me of this. Oh and what is a good setting to torque to before you crank up the truck and let it warm up or do you drive it and let it warm up that way?? I'm tryin to figure this out, so help me if you can, thanks.
 
I believe the reason that you would loosen them is for extra squish on the gasket. Kinda like if you are trying to push a car out of a hole, you sorta get a rocking motion to help it get out... at least that is what my theory is.
 
What too technical talk for you? If you want to get the engineer talk for this, why dont you call ARP, they have guys that design these for a living. I am pretty sure that they can explain it in a manor that would be more in keeping with your high standards.
 
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