Oil pan studs or bolts?

[lippy]

Here is the pan rail I made. It's not as slick as Wiki's, but I liked making it myself. I used 308 SS bar, 3/4" x 1/8", cut it, and TIG welded it. In order to get it flat and reasonably clean, I tacked it on one side, then the other on each joint, and then welded. I found that if I paid attention to the cuts and made them clean and tight, I could fusion weld (no filler rod) and the welds turned out much better. At any rate, it took a few hours (probably 5) but I'm happy with the results.

Now on the studs vs bolts... Between the two gaskets, the reinforcement, the pan, and the windage tray, the aggregate thickness is about 0.48", maybe a bit less. The bolt holes in the Pond block are about 0.5" deep, but they vary. If I use bolts, the 1" ones may bottom out, and the shorter ones (0.812") would only go into the block about 0.3", which isn't enough. I'm told you want to go 1.5x the bolt diameter for steel and 2x for aluminum, so for 5/16" bolts I would need the full 0.5" in my block, as it's aluminum.

Which leads me to studs. I have the Canton ones already (which loosened) but I'm thinking it may be worth it to spring for the ARPs. They are slightly better because (1) they use a higher strength material and finish, and I can torque them to 20-22 ft-lb, which will better take advantage of the reinforcement I made, and (2) they use coarse threads into the block, and fine threads on top, which i'm told provide better clamping force, and are less likely to back out.