Sorry for my bad math! 9 per side so 18 total - makes sense. 2 spares are never a bad thing, On the second header install I did, we reused the OEM hardware, Completely fine.

I would recommend just sticking with OEM gasket. Thats what I will do if and when I remove mine to redo the gasket/studs.

 

Yup, Kline headers come with a cheaper gasket. Best to stay with OEM.

 

Also with the new ARP studs/nuts, will they work for OEM headers? If so I want to have a solution when I switch back to stock and not do this over again.

 

As long as they are dimensionally the same, I don't see why not.

 

Well, as it turns out, the ARP 400-8022 would work great with OEM manifolds, but as I measured and mocked them tonight, these studs might be about 2 mm short for aftermarket headers (or at least the Soul ones), as the flange is 10 mm thick, compared to 7 mm for the OEMs. The OEM studs are 41 mm long and I figured since the ARPs on that kit are 38 mm it would be close enough, but I didn’t take into account that the ARPs have a non threaded section at the end that has the Allen opening for easier installation, but effectively reduces the threaded length to about 35 mm. That in addition to the thicker flange and the ARPs thick washer, makes the nut engagement 2 mm short of complete. I could just back out the studs 2 threads off the head and would give me complete nut engagement but I have opted to order the ARP 400-8024 which are 51 mm long and try those before I decide which ones to run. I think ARP 400-8023 would be perfect as they are 45 mm (essentially same as OEM in terms of threaded length), but unfortunately those seem to be back ordered everywhere until February

I should be getting the 51 mm ones by Wednesday so we’ll see, hopefully they won’t be too long to interfere with the tubes and allow the short 12 pt socket I have to go all the way in to engagement. I’ll update next week.

Couple of pics for fun.

 

Don't back out the stud. Doing that, you lose the benefit of using a stud. It needs to be properly installed/seated into the threads. There should be install instructions to follow from ARP, or maybe on their website.

We've not installed Soul headers, but if you have a stubby flex socket you should be good.

 

51mm might be a little long. Just curious if you will be able to slip on the headers with 11mm extra length over stock. The 45mm might be the best length.

@VektorPerformance do you reuse original OEM manifold gaskets when doing header install or you use brand new gaskets? I inspected the gaskets I removed from my 10K mile car and they see, "fine" - but if I am going to redo the job I dont want to take unnecessary risks.

 

No never. Once the bolts are tightened, if the gasket comes off (used or not), it goes in the trash. We include, and only use OEM gaskets when installing headers.

 

Thank you!

 

OK, I can confirm that the ARP M8x1.25x51 studs work in our application at least with the Soul headers. They embed all the way in the heads, and obviously plenty of outside thread to engage the nut fully with some to spare. The 45 mm ones would have been ideal as the 51 mm make it a little harder to mount the header (just have to push the turbos out a little more to clear the turbo studs), and get the nuts and sockets over them, particularly on the passenger side header, but nothing too terrible. I would have gone for the 45 mm if they were available, but again everywhere I looked, they seem to be backordered till February and can’t wait that long, need to get this part of the project going and get her on the ground someday soon and test it. Too impatient.


Pics:



ARP 51, OEM stud (41) and ARP 38

Final location of the nut after accounting for aftermarket flange and ARP washer.

Used Nickel antiseize and snugged them down. These things as quality hardware no doubt.

Jut enough engagement to reach tightening with a short 12 pt 10 mm socket and wobly extension.

Happy with the end result.

 

Can you share the links to where you bought the hardware? Apologies if I missed it.

 

Amazon, just search for ARP 400-8024 (though as above, I would recommend ARP 400-8023 if available).

After doing this, I would say, as Vektor and others in this thread had pointed out, that if you don't wind up pulling studs off the head when you remove the OEM manis, and the outside threads look decent on the OEM studs, I might just have run 12 pt replacement nuts (rather than the tripple square corroded OEM nuts) over the OEM studs and called it good. But once I pulled one of the studs, my OCD kicked in and I decided to go this route. I plan to keep this 991.2 for ever (pretty much), so since I had her up on the lift at home, and no huge rush, I also wanted to get the best hardware in the event that I have to pull the headers again down the road, and ARP is as good as it gets in aftermarket hardware, and can be reused if the studs needed pulled out. Again YMMV.

 

Thank you I am going to order those up now!

 

Figured I post this here for record keeping in case it helps someone down the line.

Today I finished installing the headers, used the brand new gaskets supplied by Soul on the head side and the turbo side, I put anti-seize on the threads of the studs as well as the washers.

I then torqued the head side nuts in sequence, starting at the center and moving to the outsides which made the most sense from what I read, I did three rounds at 11 ftLb, 15 ftLb and a final 18 ftLb. I plan to come back and re check torque spec after the first two hot/cold cycles.

Below are the part numbers for the OEM gaskets for reference. On the turbo side, I elected to keep the OEM studs, I simply tooked them off and wire wheeled them, except for that bastard one on the top driver side where I’ll use one of the bolts supplied by soul. Soul also supplied new copper clad nuts which is what I used.

I left the turbo side loose until I mount the catless pipes.

Head side OEM gasket: 9p1 251 261

Turbo side OEM gasket: 9A2 111 215 00


Turbo side studs fore/after wire wheel.




The money shot.

 

Thank you, @TX 911, for choosing SOUL and putting in the time and research to find an alternative stud solution. We may offer this as an upgrade with our headers. I'm sure the forum would love to see the results of any other endeavor you choose to tackle, let us know if we can work with you to continue to bring more information to the forum!

-Mike