torque specs
 

which torque specs would you use for heads? ARP head bolts calls for 65ft pounds and merc 75ft pounds.

Re: torque specs
 

I always torque the arps to 75 regardless and make sure you seal the threads well with a good thread sealer such as permatex#2.

Re: torque specs
 

ARP's recommended torque settings are usually lower because they tell you to use their moly lube which according to them gives about the same amount of bolt stretch with 10 ft-lbs or so less torque. For example, for the ARP head studs I'm using, they recommended 70 ft-lbs with ARP moly lube (for iron heads) and 85 ft-lbs with oil.
They only recommended 65 ft-lbs w/ moly lube for Alum. heads, so I followed AFR's instructions and torqued mine to 75 ft-lbs in 15lb increments.

Re: torque specs
 

When I redid the top half of my 525SC, I used new ARP head bolts, the ARP sealant/lube and their torque specs. No problems after 50hrs.

Re: torque specs
 

Just like MESA said, use a good sealer like #2 Permatex and use Moly lube with oil under the head bolts and washers. Make sure also you torque in steps as well. After sitting for about 20 minutes or so I usually go back and loosen one bolt at a time and re-torque to its final torque speck. This helps in bolt stretch and tightness. Some do and some don't. Its seems to work for me so I keep doing it.

Good luck.

John :D