straight_six

Anyone know the tensile strength of stock head studs?? And also what are the stock studs torqued too??? tia

homewrecker

I don't know the tensile strength of stock head bolts but torque is 77ft lbs + an additional 90*.

straight_six

so what do you think would happen if i tryed to torque my stock head bolts to 130lbs?? was talkin to a machinest today and he thought it was joke what they charge for head studs

tatkins85

there only 350. if i were you and they are off already i would buy head studs. not to mad, and you alreayd have the stock once out.

straight_six

i havent torn anything apart yet... just got twins put on and just tryin to figure out all this junk...

tcr

My head bolts were torqued, then re-torqued a couple days later to 110 ft lbs(o'ringed head). No issues.

jmccart

How much boost ya' running on them stockers?

tcr

60psi max.....

jmccart

Sweet news.

XXLTEXAN

60 PSI!! On a stocker??

White97GTVert

His sig says HTB2 62/14....

BossHogg

Ya isnt 60 pushing it?

straight_six

i just dont get why i need to by new studs if i can torque my stock studs down more??

White97GTVert

Because they were designed to be stretched one time, and one time only. When they get torqued to 77 ft lbs, then a 90* more that is the final set point and streches the bolt out a little bit. Once that has happened they shouldn't be torqued again.

Thats the way it is in the gassers I've always worked on anyways. Maybe these are different but I think its just cheap insurance.

What is the actual torque on those bolts once they have been turned an additional 90* past 77 ft lbs... Since I've never tried retorquing the stockers I have no idea. I imagine its somewhere in the neighborhood of 100 ft lbs going an extra 90. Guess of course.

tcr

Not w/ an o-ringed head. I'm probably good to 70-80psi I would hope. I am getting out of my turbo's efficiency range though.