today finally got a chance to test our method for 1/2" head stud install and pull out strength. well we would have been happy and satisfied with 140-150ftlbs torque on the nut, but didn't get that at all. we far exceeded it!! my torque wrench goes to 160ftlbs. went in 10lb increments starting at 110lbs. after 160lbs my torque wrench would no longer click (cause it was maxed) and i still managed to get another 1/4-1/2 turn on it before even me standing on the block could not turn the wrench anymore!!!
i left the block for about 10 minutes, checked again and it had held. i started to loosen the bolt and once the torque was off of it, i was able to back the stud back out with my fingers the whole way, so there was no thread distortion AT ALL in the block!! the test was done with the cylinder head and no head gasket. the bolt is normally rated at 105lbs torque so this is an exceptional way, with alot of holding power still left in the block threads, to add 1/2" studs. to put it in perspective, i had so much torque on it, the nut actually started to seize on the arp stud and the washer dug into the cylinder head.
the bolts we are using are a full 0.5" shank. it does not taper through the center like the stock style studs. the center of the stock stud is 0.375".

we have gotten arp to package these and will be available to order at any time. $250 is the price!!!! you can only order through me as it is custom from arp. this is a process that is very easy and machine shop prices should not crest $300. we are offering this service along with complete builds or shortblocks.



messing around further today, i wanted to create a way to easily fill this darn motor with water the first time!!! and making further water fills a snap. the pictured piece is a water passage cover that is the highest possible point to fill the motor. it is located under the lower plenum. access is impossible once the intake is on, but it is the best place to fill and i'm sure is how the factory originally fills the motor. it can be made with hard lines if someone desires, but reinforced rubber or braided can be used also. connect one line near the bottom of a bubble tank, and the other near the top. a screw on cover to give access in order to fill the tank. mount the tank as high as possible on the rear firewall. fill the motor from that spot, and you can fill the motor to nearly full on the first shot!!!



would suggest anyone with their motor apart to take this simple step to avoid wanting to pull your own arms off trying to fill the car with water!! hahaha

 

Hey I like that water filler thingamuhjig. Are you going to be selling these anytime soon? I just got finished re-filling my water since I just put on new Samco's.

 

Can you test it with the stock and cometic gaskets to see if torqueing the studs that much will distort or crush the gasket?

 

just need to design the bubble tank for my car. should be a snap though. will post pics when i actually install it and see how much interest is in it.

 

if proper head torqueing is done (start at center out) it will work perfectly.

 

What, why would you do that? Over tensioning is just as bad as not tensioning enough...

Torque tensioning can be influenced by oil used etc...

You are supposed to torque down those studs until they EXPAND a certain amount, which you measure with a special tool (ARP or other brand Stretch Gauge). This way you are sure they're exactly torqued down right...

http://www.arp-bolts.com/Tech/TechInstall.html

Danny

 

you are 100% correct. this was a pull out test. it was a test to see how much the threads can hold to make sure the rethreading process was done to satisfactory specs. no you do not tighten the 1/2" studs to 180ftlbs. if you read all of my post, it says the bolts are only speced to be torqued to 105-110ftlbs (will get the exact specs from arp, it may be less). which is what you will torque them to on the motor. this is to show the process we are using will be able to take full advantage of the larger studs by having solid threads that can take much more pull out strength than the bolt will be torqued to.

 

scott PM me with details on bolt kit machine procedure, thanks!

-George

 

Congrats! Good to see my heads and block went to good use.

 

yessir! still got another trick, done with that in a day or 2. your blown block and heads have alot of holes in them now, more so that the rod put in it, lol.

 

thanks for doing this test. i was very curious but did not have a spare block to put this effort into. your test data makes me feel secure and i will definatly have to pick up a set of your 1/2" ARP studs for my engine I am building right now.

 

So is this supposed to cure the head lift problem that people going for insane power are experiencing?

 

not a complete cure, but a big step in the right direction.

 

So what else are you planning on doing in conjunction with the 1/2 head bolt? Or would u have to kill me if you told me

 

i am not sure if i personally think that 1/2" headstuds is the total cure, but i have been planning on converting to them this time around, and am very happy someone tried a torqueing test, this information is exactly what i needed to make up my mind on if i trusted the 1/2" stud threads or not.

 

something like that hahahha. it will all come out very soon.

 

Where about do you believe or have you experienced head lift on your own car? After how long?

 

will pull my headgaskets tomorrow to take a look. very interested to see where the leaks will be. mine is so bad now i can't even drive around like a grandma without loosing water. first signs of it were about 2 months ago.

 

How much power where you running and for how long before you knew you where leaking water? Sorry for all the questions...just trying to learn.

 

a touch over the 600rw mark. but i never really pushed it super hard. i first got indications of it on a trip to san diego to meet 350ZNV and the guys at VRT for the performance nissan meet. i was nearly out of water when i got there. having a feeling i was getting light detonation on the lower grade fuel in cali and that started the process. it was fine for awhile driving in oregon alone. but you never know.