How do the 14mm headstuds compare to the ARP 12mm ones and the ARP ones that are 3X's the cost? How hard is it to have the block drilled and tapped?
14mm Headstuds
- Thread starter ZR1160
- Start date
Guy just finished upgrading my LBZ block for the 14mm studs. The head's will need to be drilled to accept the studs as well. It would be best to contact him for a price!
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Well IIRC the 14mm studs were 750 ish, add the machine work in and i think youd be getting near the price of 1500 for tha 12 mm 625s. Im still not sure which way to go.
What is the strength difference in going from the highest strength 12mm's to these 14MM's? I haven't heard of any problems out of the high strength 12MM studs, but do you think that high strength 14MM stud's will eventually be needed as the DMAX gets pushed further and further?
Doing the math here, the aluminum heads won't be real happy with the clamp load a 14mm stud is capable of.
14mm stud 180k psi tensile, torqued to 75% of tensile equals about 29k lbs of clamp load.
29k lbs on a 3/4" washer equals 65k psi.
Best I can find is, the compressive strength of AL is 77k psi (not sure if this is forged, billet, cast, I'm guessing cast is lower???)
Which means the clamp pressure is only 15% under what the material of the head can handle.
I'm certainly not a engineer, so somebody correct me if I'm wrong...
14mm stud 180k psi tensile, torqued to 75% of tensile equals about 29k lbs of clamp load.
29k lbs on a 3/4" washer equals 65k psi.
Best I can find is, the compressive strength of AL is 77k psi (not sure if this is forged, billet, cast, I'm guessing cast is lower???)
Which means the clamp pressure is only 15% under what the material of the head can handle.
I'm certainly not a engineer, so somebody correct me if I'm wrong...
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I think the idea here is that the 14mms are cheaper by half than the 12mm 625 studs.
12mm ARP-2000 material head studs: Torque to 125 ftlbs.
12mm ARP-625 material head studs: Torque to 150 ftlbs.
SoCal 14mm Head studs: Torque to 190 ftlbs.
I'm at home now, so I don't have pricing at my finger tips.
You obviously need to drill and tap the block, ream the heads, and alter the head gaskets.
I feel the overall stability of the larger OD fastener is much better.
We have installed the 14mm studs on a number of our builds and they have done quite well.
12mm ARP-625 material head studs: Torque to 150 ftlbs.
SoCal 14mm Head studs: Torque to 190 ftlbs.
I'm at home now, so I don't have pricing at my finger tips.
You obviously need to drill and tap the block, ream the heads, and alter the head gaskets.
I feel the overall stability of the larger OD fastener is much better.
We have installed the 14mm studs on a number of our builds and they have done quite well.
how many people are having failures with the 12mm studs? This is all news to me
welcome back josh
Bigger studs
How bad will this effect the ring seal? I know the block moves a lot with the 12mm studs so if you make the hole bigger I would think it would move more. I do like the idea of more surface area on the bigger stud. Jeff
How bad will this effect the ring seal? I know the block moves a lot with the 12mm studs so if you make the hole bigger I would think it would move more. I do like the idea of more surface area on the bigger stud. Jeff