6.4 ARPs... 195 or 270ft lbs?

[C'roy78stroker]

Long story short... trusted a local "performance" shop to install headstuds... not even 4k miles later, head gasket has given up the ghost. Im gathering parts to install while I have it apart, nothing drastic yet, but I have been reading that arps specify a 270 ft lb final torque value but ive also read about torqueing them over 200 can crack the block toward the intake manifold side just below the deck. And that a "safe" torque limit would be 195... Anyone's opinion, experience, or info will be much appreciated.

 

[TXAG07]

I think 275 is what they call for, but I believe Morgan said he was doing 250 and then 225 in weak areas on his builds. I'm sure he will chime in. Good luck on the next round. My studs will be going on in a few months.

 

[V-Ref]

 

[V-Ref]

http://swampsdiesel.com/site/instal...df_instructions/6.4LHeadStudInstallation2.pdf

 

[V-Ref]

http://powerstrokearmy.com/forums/showthread.php?p=925767#post925767

 

[madman1234509]

http://swampsdiesel.com/site/instal...df_instructions/6.4LHeadStudInstallation2.pdf

This link is for A1 studs, completely different torque spec then arp.

Do a search.... Just follow the directions. Arp specs are 275ftlbs. Make sure your block is surfaced properly and there are no cracks in the head.

 

[V-Ref]

This link is for A1 studs, completely different torque spec then arp.

Do a search.... Just follow the directions. Arp specs are 275ftlbs. Make sure your block is surfaced properly and there are no cracks in the head.

The link was to provide perspective.

OP...the torque spec listed in Elite reference below for H11s is 195 ft/lbs

http://www.powerstrokearmy.com/forums/showpost.php?p=25783&postcount=1

 

[SEABEE08FX4]

275 ft lbs on the final pass, harder materials like H11-H13-625 and so on require less.

 

[madman1234509]

The torque is less, but the material is harder. So even though the final torque is less I'm pretty sure they put close to the same clamping force on the block.

 

[sootie]

The torque is less, but the material is harder. So even though the final torque is less I'm pretty sure they put close to the same clamping force on the block.

maybe but the force on the block with arps at 270 and an H13 at 270 is a big difference.


the torque values must match the stud material.

 

[madman1234509]

That's what I was getting at. He keeps referencing h11 studs being torqued to 190ftlbs, but it's probably putting the same amount of stress on the block as an arp at 275 because of the material.

Like I said. Just follow directions that are given with whatever brand stud you have. If you're that concerned follow up with the people that did crack their blocks. I bet most of it is user error or uncalibrated torque wrenches.

On a side note. A recent magazine did a write up on head studs. It had a picture of someone using a torque wrench with a pipe on the end of it..... No wonder people are cracking blocks.... Here's a real torque wrench.

 

[G Racing]

Torque the studs to the specifications on the instructions that come with the studs. Do not over tighten the stud to the bottom of the hole or you may crack the block.

 

[TRUBBS]

does anyone bottom tap the stud holes like the 12v cumminG's guys do?

what about the whole Teflon paste deal that elite was/is doing?

 

[B585Ford]

maybe but the force on the block with arps at 270 and an H13 at 270 is a big difference.


the torque values must match the stud material.

...and lube. I don't think there is too much of the old lube for ARPs left so it won't matter now, but like the material, the lube used does make a difference in what force/stress is on the block.

 

[V-Ref]

...and lube. I don't think there is too much of the old lube for ARPs left so it won't matter now, but like the material, the lube used does make a difference in what force/stress is on the block.

:whs:

And just to make sure the OP and other readers get the point/perspective I was trying to share from the first couple links....

no, but if we're doing it, we o-ring the head as well.

cheaper than a cracked block.

 

[Fordtrucks]

I spoke to an ARP tech before re installing my studs. He told me to always TQ them to spec. He said the stud is designed to be stretched a certain amount when torqued. He said your not tight enough, the stud may stretch more under load, causing your gaskets to fail. He also said you can re use them as many times as you want but to never torque them any higher or you'll over stretch the stud and it will fail. The guys that tell you to add 10 lbs more every time you re install them are dead wrong! He also said its very important to use the exact lube the stud calls for, nothing else. My block isn't cracked, second time at 275.

Use a calibrated, 3/4"TQ wrench. No extensions. We used a TQ multiplier. Don't bottom out the stud in the block.

 

[Csilva187]

Little thread sealant and don't shy away from the lube lol. 275 here also.

 

[dsberman94]

When we did the 6.4 studs we torqued them the first two times then went and ate and had a beer. Came back and did the final torque to 27x. No cracks.


Posted from ***itville, USA

 

[C'roy78stroker]

Thank you guys. Looks like it will get 275 again. :ford::toast:

 

[groove]

275 as well, no issue. Don't skimp on the lube.