Rb head studs comparison

[BK]

12 hours ago, Old man 32 GTR said:

One engine builder stated he won’t use 625’s. 

I wonder if it's because of the high recommended torque. From installation experience, 2000's torqued to the recommended 110ft/lb "feels right" when doing it. Done a few of them, but after doing the 625's once, 130ft/lb for them feels bordering on too much.

I was worried I was going to pull the thread out of a brand new block ! Wouldn't be surprised if someone has, considering the stock head bolt final torque is only 76 - 83 ft/lb and is really only what Nissan engineered the block to handle.

[White GTS-T]

More to the point, the alloy head starts to warp and distort under such clamping pressure.

[GTSBoy]

2 hours ago, White GTS-T said:

More to the point, the alloy head starts to warp and distort under such clamping pressure.

That's what I was going to say. It's a lot of compression fed through the diameter of a washer.

[Dose Pipe Sutututu]

Cometic head gaskets need the block & head to be perfectly flat to seal. So if you were just servicing the head, popping it onto a stock block it will leak.

Tomei & Nitto head gaskets are somewhat more forgiving due to their design, you could say it has an o-ring around each cylinder.

I've put 2 bar of boost into my motor with ARP2000 studs and it has seen nearly 100 laps of Wakefield Park before it died from oil starvation. No evident signs of coolant being pushed out or combustion gases in the coolant (black specks).