ARP 625's or Standards?

Greg, what process do you recommend for 625's in a 12V that has been fire ringed?


I was told to torque in increments up to 150 then fully loosen and tighten each one in sequence right to 150 then repeat 3 MORE TIMES?!?!?

did i explain that good?
 
Highfinance97 said:
Greg, what process do you recommend for 625's in a 12V that has been fire ringed?


I was told to torque in increments up to 150 then fully loosen and tighten each one in sequence right to 150 then repeat 3 MORE TIMES?!?!?

did i explain that good?
Click to expand...

Yes you torque in increments, (I loosen and retorque each one till I hit my desired torque) then after at desired torque, you start engine, bring to temp, shut down, let cool, then retorque again, by loosening each stud one at a time, and retorquing. Then do this again,, I usually like to get a few miles on after the second though before I do the 3rd
 
all ARP studs should be torqued 3 times in the life to burnish the black oxide off the threads , and then no retorques are needed on MLM gaskets . On a fire ring where you not pressing in to a composite gasket you should not need retorques after the initial 3 on new studs
The reason is that if you predicted crush on the head gasket is correct , and the depth of groves are correct then retorques are not exercising the crush on the ring.
There are a lot of myths out there , and some are just silly when you talk to the fastener engineers.

A lot of this was left over from the days before good head studs , and people did what they had to to try and make head bolts work.

Kind of like decompressing , its great on making head gaskets live , because it takes all the bottom end away . With CR its totally not the right thing to do , I have even gone far as putting slightly more compression in to build bottom end , this is possible by tuning for the compression .
 
I agree 100% Greg,, there is no reason to lower compression in a common rail... it is a silly myth to do that in my opinion
 
If you are gonna go high HP or high RPM, get the 625's...A few dollars now is alot better than hydro locking the motor because the 2000's failed and now the motor has to be tore apart, buy new connecting rods, replace a cracked head and pay for the porting and polishign all over again...Yup, been there and done that
 
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BigDodge said:
Std arp's.fire ringed, 120psi,5000rpm, 9.48@145.
Click to expand...

RPMs will reduce cylinder pressure. The common rail makes torque like non-other. Torque = cylinder pressure in simple terms. Your setup it out of the norm because you can reduce the pressure with the rpms and most of the people here are not going to fire-ring their setup.
 
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