Wow these new ARP custom age 625+ studs are one tough studs. 125 ft. lbs used to seen like allot with my old standard ARP 2000 but torquin those bads boys down to 155 ft. lbs with all those studs doing 3 torque down's per studs is a ton of work. I'd like to think of myself as in pretty good shape but this time I'm plain wore out. What is so impressive about these studs is when you get down to about 155 ft. lbs your can really feel them just tighten down with a death grip. When doing the old ones to 125 wasn't that tuff, but 155 all around sure is allot of work

I don't think my head will be lifting anymore, very impressive material

 

I received mine Thursday, waiting on my head to get done for my 04. Like you I know it will wear me out by the time I am done with a finish torque. Tim

 

These sound like the studs to get for a high horsepower,boost application.

 

For the dmaxes too. I know of a few motors that will/do have them.

 

Is 155 ft. lbs. what was specified in the ARP instructions for those studs? I looked on their web site and couldn't find the installation instructions.

 

Depends on who you talk to in the racing world or ARP, factory rep told ,me that 5-10 ft. lbs didn't put you in any safety concers. I bet those studs would go to 170-180 no problem. Just needed a bigger torque wrench What was really interesting about this new material is that when you would tq down the 2000's it would get tighter but never really lock down hard ya know? I ended up snapping on of the old ARP's and it really started to stretch around 165 ft. lbs and got super weak from there. Its a was a bag tq wrench plus we were being stupid. But as you were massivly overtorquing the 2000's it didn't require much hard effort. But the 625+ studs really give you that hard locked down feel. By the time you get to 150-155 it really gets tough to gem them down, especially towards the back of the block. If I wouldn't have put in these new 625's it would have been my final and fourth retorque on the ARP 2000's. Another interesting thing noticed is that after it was all said and done and torqued down hard (no stretching feeling) pretty much all the valves had to be readjusted again. I'm using the .20 12V marine gasket and it crushed even further down.

So basically I learned two things. 625+ ARP material is insanely strong and you better be up for the task and now I"m 100% sure that 3-4 retorques on these 24V are the only way to go. We also put a thin layer of gasket coating/sealer on the block to insure no spillage from the coolant to oil passages. I've called tons of shops and some say Yah to retorques and some say it's not necessary.

 

I know some will disagree and I am by no means any expert but the guy at ARP told me that these custom age 625 plus studs are stronger than 14mm studs that get machined in our block. Now of course if they made 625's in 14mm studs the game would be over. But for now it looks like we finally have something so we don't have to machine our block until we get into extreme power levels. I would suspect the next weak in the cummins would be the rod bolts

 

Maybe... but the cracked caps make a huge difference in preserving con-rod bolt integrity.