Re-torquing ARP headstuds

[4g63tcrazy]

Read from like the 3rd page on of the link I posted. Also when you do the copper spray you need to do it VERY evenly and you can easily over spray in some area's making the surface uneven.

[scheides]

Originally Posted by 4g63tcrazy

Read from like the 3rd page on of the link I posted. Also when you do the copper spray you need to do it VERY evenly and you can easily over spray in some area's making the surface uneven.

Haven't gotten that far yet, but on page 2, there's some interesting info.

It says that if arps are used and torqued just beyond the recommended torque (which I think is fairly common practice) and THEN the head lifts for any reason, the ARP studs are not to be used again, as they can become stretched and integrity compromised.

Has anyone locally experienced this? If this is in fact true, it could certainly be why my HG is going out again after only 10k miles. The head lifted last fall and when I replaced the headgasket I re-used the same set of ARPs.

Are the L19's really $250? Someone pinch me....can my mere 400whp 4G63 really need these?

[MustGoFaster]

Originally Posted by scheides

Haven't gotten that far yet, but on page 2, there's some interesting info.

It says that if arps are used and torqued just beyond the recommended torque (which I think is fairly common practice) and THEN the head lifts for any reason, the ARP studs are not to be used again, as they can become stretched and integrity compromised.

Has anyone locally experienced this? If this is in fact true, it could certainly be why my HG is going out again after only 10k miles. The head lifted last fall and when I replaced the headgasket I re-used the same set of ARPs.

Are the L19's really $250? Someone pinch me....can my mere 400whp 4G63 really need these?

By "just beyond" are you talking ~5ft-lbs? If so, I doubt 5 ft lbs over would cause any issue. Depending on how close to the yield strength the TQ spec is, it could matter.

Here is ARP's genral info page :
http://www.arp-bolts.com/Catalog/Cat...talog_0024.pdf

Mine are TQ'd quite a bit higher than the spec. I would not reuse them at this point, as I should be ridiculously close to the yield point. (Hence why I picked the number I did)

And just be glad L19's are that CHEAP. ARP's for a 6G72 are $300. There are 16 VS 10, and they are a little longer, but 3X the price WTF!!!

[4g63tcrazy]

Originally Posted by scheides

Haven't gotten that far yet, but on page 2, there's some interesting info.

It says that if arps are used and torqued just beyond the recommended torque (which I think is fairly common practice) and THEN the head lifts for any reason, the ARP studs are not to be used again, as they can become stretched and integrity compromised.

Has anyone locally experienced this? If this is in fact true, it could certainly be why my HG is going out again after only 10k miles. The head lifted last fall and when I replaced the headgasket I re-used the same set of ARPs.

Are the L19's really $250? Someone pinch me....can my mere 400whp 4G63 really need these?

Page 3 and on is alot more in depth info and more people running high hp giving their experience. If you lifted the head and torqued the head studs down to the same torque as the first time. Then I would have to say that is FOR SURE why you're head lifted again so soon. If you lifted your head, you stretched the headstuds. Then if you torqued them down the same as before. It's not gonna hold the head down as good second time around.

[scheides]

Originally Posted by 4g63tcrazy

Read from like the 3rd page on of the link I posted. Also when you do the copper spray you need to do it VERY evenly and you can easily over spray in some area's making the surface uneven.

Ok, finally read through that entire thread, no discussion of copper/no copper, but I think I want to go no copper this time around.

The head studs will get replaced no matter what, but there is a tipping point for deciding between a new set of standard ARPs and the L19s: ultimately, my goals are around 400whp (dyno dynamics). Yup, so I'm pretty much there now and happy. The safe limit of the stock bottom end is around 420whp. Let's say I get the head ported while it's off, install it with L19's and get retuned and make a peachy 425whp. If for some reason the same conditions are met in which I lifted the head in the first place, and the L19's hold, what will happen? Will the bottom-end take it? Will I much rod bearings? Will I blow a hole in my block?