I would see what ARP makes for the next largest size.

I do not have confidence in myself with drilling/tapping and if I were in your shoes I would take it to the most trusted machine shop you can realistically find ... even if it means crossing state lines. You are at a very very very delicate spot right now where if this gets funkerd up you are essentially looking at a new block. Do it nice or do it twice...

 

Next up is 1/2" studs. Drilling and tapping is easy but a dellicate process. You have to make 10000% sure the block is level. I have done it on a few different parts internal to the engine but nothing as critical as head studs.

 

thanks for the input guys! looks like I have some thinking and research to do, Ill let you guys know when I decide what to do next. probably going to start by calling ARP and seeing what they recommend and what products might meet my needs

 

https://arp-bolts.com/kits/arpkit-de...?RecordID=3928

Go big or go home....Now you can run ALLLLLL of the boost!

 

Head Studs should go in Easy - By Hand......
The Allen head is just so you can do it with a tool instead of using your fingers.

 

Well I tried to clean out the threads and tap further down into the block and see if I can repair or make usable what was still there but no dice the threads are just too shot and they stripped out again before 50 ft-lb so I am moving on to the next size up to use the GTR materials. Here are some pics of me attempting to repair the threads


Thread tap and thread chaser

Taped off the block to prevent any material from entering the block

Line closest to threads marked OEM deck height in comparison to the thread depth, the next line down is how far down I will depen the threads

Cleaned and taped out the threads

L19 stud marked for deck height at full install depth

New bolt depth in relation to deck height
and like I said above, this was not successful I will be moving onto the GTR studs

 

The Hex was damaged removing the stud after the threads in the block were stripped, locking the stud in the hole. I have, did, and always will install ARP studs by hand. If you can’t get the studs in by hand then there is something wrong with the threads that needs to be addressed first

 

Wait...wait...wait....Are you doing this all over your headgasket????

 

over an old head gasket yes, better to scratch or scuff a trashed gasket than the block surface. and i have plenty of them around I think I have 6 used head gaskets laying around and just ordered another new one this morning. every time I torque the head down there is a new gasket underneath no exceptions

 

That makes perfect sense. I was praying it was not the new one. I was 99% sure it was an old one but had to be 100% sure it wasnt.

 

yeah I can’t help but imagine what the guys over at CZP think I’m doing, I’ve ordered a new left side head gasket every week for the last month

 

Better safe than sorry!

 

Small update, work has been super busy the last week so I haven’t had time to really touch the car but I did start the thread taping process one the block, hand turned a 27/64 drill bit to cut out the old 11x1.25 threads, slow and steady. The 27/64 drill is also the proper size needed for the 12x1.25 thread tap. I started with a straight flute tap to perfectly align the tap with the hole and took it slowly all the way down to the bottom of the hole. It should be noted that the VR38DETT bolts/studs are much longer than the VQ35DE an obvious improvement given my current predicament. I plan to go through one more time with a bottoming tap to cut the threads all the way to the bottom, the straight flute has a little over 1.5 cm of flute and cutting taper before the full cutting threads. On some other notes the opening hole in the block is already the perfect size for the GTR bolts so aside from cutting out the old threads with the 27/64 bit no further enlargement of the hole was needed. The bolt hole in the head is just a hair too small so I will need to enlarge that before the head goes on as well. I think if I end up pulling the engine and disassembling the engine or building another engine in the future this will be done to all bolt holes and I’ll just go with the GTR bolts


Just placed the GTR bolt in the hole for initial size comparison

Marked the drill depth on the bit

Cut out the old damaged threads

Transferred the depth mark onto the tap

Ran the tap down into the bolt hole

 

I like where this is going, crappy how you got here but love where its going!

 

honestly right now I’m really fighting myself between doing just the one bolt or going ahead and pulling the other head and converting all the bolts to the GTR thread and getting the L19 ARP studs for the GTR keeping them torqued to 90ftlb and selling the VQ35DE L19 kit, I already purchased an individual replacement L19 stud from enjuku racing to replace the damaged one so it’s still a complete kit, maybe I’ll see if anyone will take the kit for $350 or something IDK 🤷‍♂️I feel like if I don’t it won’t ever be right

 

I would not do only one on such a critical component. In my head I would fear the possibility of the DE bolt stretching a little bit but the VR bolt not moving and warping the head.

What are you torqueing the heads to? 110 ft/lbs?

 

with the VQ L19's 90 and if i went GTR L19 still 90. when I had the block bored and honed i had them tighten the torque plate to 90ftlb to account for the distortion from torquing the heads to that speck

 

DAMN I hadn't thought about that, you make a good point. well guys Ive decided VR38 L19's it is F*** my bank account

 

I'm 99% sure torqueing heads on an open deck does not distort the sleeves like it does on a closed deck.

I'll see if i can find the resources i found when i was looking into honeing plates.

 

Do work! I love it! Good ****!

I'd torque them to 100 to 105ft-lbs ... that's where I'm going when mine comes out shortly (after this vhr swap)!