retorqing head studs?
- Thread starter sleepersupra
- Start date
I didn't think a retorque was needed on arp studs and or bolts....if I'm wrong I want to know as I just put studs on my car.
And (as IJ pointed out...thanks!) with the Cometic HG, according to their spec, the only time you don't have to re-torque is if the hardware used has been heat cycled. New studs/bolts have never been heat cycled
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jdub said:
That's the exact reason why I bought Ron's studs. Well, that & they were part of a kick ass car. :icon_bigg
rakkasan said:
With ARP hardware...not a problem (wish I'd thought of that!). With stock head bolts...potential problem due to stretch...especially when torqued above Toyota spec.
I have about 1500 miles on my car with Arp head studs and a cometic MHG. I have not done a retorque yet. Have not had any problems but assume it's not to late to do this??
I have never retorqed before, you don't have to loosen the studs and retighten them do you? Or are you just retightening and checking to make sure they are at the same torque specs??
Assume if you loosened it up you would break the original seal but just wanted to check.
I have never retorqed before, you don't have to loosen the studs and retighten them do you? Or are you just retightening and checking to make sure they are at the same torque specs??
Assume if you loosened it up you would break the original seal but just wanted to check.
jdub said:
MKIIITrbo89 said:
No...it's not too late...unless you already got a BHG that is. You want to take a breaker bar (not the torque wrench) and just "crack" them till they barely move. Re-torque to the spec you used orginally...81 ft/lbs w/ moly or 105 ft/lbs with motor oil. I'm going to go with the Toyota TRSM pattern.
The ARP specs are 75 ft-lbs for an aluminum head. Note that the higher torque only applies to a ferrous metal head.
3p141592654 said:
Sigh...here we go again :3d_frown:
http://www.supramania.com/forums/showthread.php?t=17734
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jdub said:
My mechanic I think torqued it to 75 or 80 when my engine was rebuilt, he followed whatever the specs were that came with the studs. He originally told me retorquing was not necessary. I guess it's not mandatory but better for peace of mind and just to double check to make sure everything is OK.
Also say it was originally torqued to 75, then I retorque it to 81. Is that going to hurt anything if not retorqued to same exact specs.
MKIIITrbo89 said:
If he used moly...81 ft/lbs is the spec. You could do this (assuming moly was used): Following the TRSM pattern, try the 1st one set at 81 ft/lbs. If you get the nut to turn, your mechanic used 75 ft/lbs. If it doesn't turn, crack the nut as previously discussed and go from there. You want to call your mechanic...you have to know if moly or oil was used...most of these guys are pretty consistant. The old school mechanics will almost always use motor oil
jdub said:If he used moly...81 ft/lbs is the spec. You could do this (assuming moly was used): Following the TRSM pattern, try the 1st one set at 81 ft/lbs. If you get the nut to turn, your mechanic used 75 ft/lbs. If it doesn't turn, crack the nut as previously discussed and go from there. You want to call your mechanic...you have to know if moly or oil was used...most of these guys are pretty consistant. The old school mechanics will almost always use motor oil
Thanks for the info jdub. My mechanic just works on imports, and im 99% positive molly was used. I'll ask him to make sure. and for some reason I think he torqued it to 75. So if thats the case as you said. I don't need to break them free just tighten up to 81. I will check this this coming weekend.
Also just wondering? where is the number 75 coming from. Is that used for another type of metal.
MKIIITrbo89 said:
You're welcome...until IJ pointed out the "new hardware" vs. "heat cycled hardware" issue, I always thought you didn't have to re-torque myself. You could still crack your studs if you wanted to be on the safe side...the whole purpose is to get an accurate torque reading and it won't unload the head, so it won't hurt anything.
I'm thinking the 75 ft/lbs is coming from spec for the ARP bolts, but I can't find a spec on them anywhere for the 7M. I need to call ARP on another part...I'm gonna see if they have a bolt spec sheet to send me.
It's not rocket science guys!
The ARP's come with instructions and Moly Lube just follow em and you'll be fine.
Personally I'll do the ReTorque everytime but rule of the thumb is
New HardWare = ReTorque
Heat Cycled HardWare = Personal preference.
The ARP's come with instructions and Moly Lube just follow em and you'll be fine.
Personally I'll do the ReTorque everytime but rule of the thumb is
New HardWare = ReTorque
Heat Cycled HardWare = Personal preference.