Thread: Headstud comparison

what if we cyro treat the stock bolts?

$200 is the max i would spend on studs/bolts, anything more I might as well go 1/2" studs.

Cryo-treatment only works on certain metals on some it has no effect. You might want to find out what they are made from and if it will strengthen them at all.

I could be wrong but I think the problem was more about them not tapping out and distributing weight evenly.Putting extra stress on the alum threads more so when over tightened (unlike the DSM guys who I think can get away with this) Not as much the studs being to weak and stretching. Studs that tap the bottom put the studs thread right in between the alum threads everytime. The old ARPs also have around a half inch less thread and don't tap the bottom of the block because they were designed for Nissan's other iron block that sometimes go directly into coolent passages and have no bottom to tap out on. There are also different strengths of the metal alum being soft and easier to strip those threads that are already on a thin line.

I just find it hard to believe that a bolt is going to rip out 2" worth of thread before stretching. Stretching is the real argument here. I believe that because I have only heard of like 2 ppl running these studs that have ripped threads out of the block.

Aluminum or not, it is hard to believe the threads are going anywhere especially where the rest of the block is going to be reinforcing the threads. I think there may have been something else that caused that. The arps would most likely stretch out before the threads come out.

Perfect example of this: I was tightening some arp rod bolts once when my torque wrench decided not to click. The bolt stretched out and broke, and the bolt could still be unthreaded by hand. The rods are steel but I think the threads are going to be fine in the block.

I am going to take my chances with the arp bolts. I have no reason to not trust them as I have had zero issues since day one. These bolts have survived 20+psi of boost and several spikes! I have yet to have a problem with head lift or even stretched threads.

Yeah, I'll call them today to see if the part number I have is the new set. I think I'll just end up using them, as I'm getting short on time.

I got my new studs and they are the same number and size as my other set on visual inspection.

if they have not changed their design... they have failed again.

Well I don't get it. Has anyone talked to ARP yet to find out wtf? Maybe I will call them today and talk to them. Either way it looks like simple parts like these studs are going to get harder and harder to find. I will just use the arp ones. If anything happens to go wrong then I will just have to have a friendly talk with arp.

So how many people here with an SR20 have actually had a problem that can be directly attributed to using the ARP studs?

Even Rawkus can't really say that his VET gasket failure was directly caused by the ARP studs, the Cometic gaskets have failed on numerous engines.

So anyone? Anyone have threads rip out of the block here? Maybe ARP doesn't feel the need to completely redesign the bolts because they are confident they will work fine. Maybe we are all worried about something we shouldn't be worried about...

I will be calling ARP today, to determine whether these headstuds were in fact redesigned, or not. I just ordered my A'pexi headgasket from Mark @ Mazworx this morning, so at least I won't have to worry about the C* variant. Guess I'll find out how everything holds together, when I get it running and tuned.

Yeah I might just sell these and go with some Greddy units and call it a day. I don't wanna spend the cash and have it damaged for something like this.

OEM OEM OEM, what the hell is worng with OEM.

Here are a few questions you can ask yourself to determine headbolt/stud necessity:

1. Am I pushing 500whp+?
2. Did I spend 6k+ on my motor build?
3. Do I want to risk my 6k+ engine on a $500 part?

If you answer no to 1 then OEM are fine.
If you answer yes to 2 but no to 1, OEM are fine
If you answer no to 3 spend the money on good studs/bolts

That was a little simplistic, but aftermartket studs/bolts are not necessary for most people's builds, especially when the cheapest viable option is JUN for $300. OEM hold up great and are more then enough for daily driven 350+ and track time 430+ and they are $50, so what if you have to replace them when you change HG's. If you are pulling your head so much that your OEM bolts are costing as much as JUN/Tomei/Greddy then something else should be addressed in your engine. I have never heard of head lift on a motor 500hp or less that used OEM bolts, if you have please share.