Thread: 90 ft lbs torque on stock headbolts

guys,

opinions needed:

I misread the FSM instructions on torquing the stock headbolts.

Attempted to install a fresh set of bolts with a vet metal HG.

my final torque figure was 90 ft/lbs!

used the method to tighten and loosen however.

what could be the repercussions?

someone suggested I may have destroyed the HG and I will eventually start to lose coolant.

also, would compression results show if there would be a damaged HG? (ie. overheating motor)

also finally has anyone measured what that 90*+90* torque yield would result?

stretched head bolts. you would need to pull them out and measure them to find out. If they did not stretch out of spec just torque them to the factory spec.

I've accidentally over-torqued ARP studs to 90 ft-lbs when they should have been around 60. The engine took it like a champ and nothing bad ever happened. We also didn't re-torque them as you're supposed to do after they settle, because we weren't going to touch them after finding out the mistake. We hoped for the best and nothing bad ever happened. This was on a BMW engine, pushing 3x factory power.

Not sure if that helps you any? :o

vvl head bolts are still 6.23" guys?

fsm states 158.2mm(6.228in). I would say your fine.

thanks man!

does the compression test show a leaking HG?

what other methodologies to test for a leaking HG

Send oil sample out to lab?

Smell the oil, smell the coolant?

A comp test will show a head gasket if the leak is big enough between cylinders. You need to heat cycle the motor first before the head gasket will make a complete seal.

its been driven. having cooling issues, hence the topic