Im getting read to have my head o ringed and studs I was looking at 12mm ARP and A1 which is better or are they the same? Do you have to bottom tap when installing studs? Any input would help

 

I was told A1 studs are better but I feel with the price of stud kits I would go the cheapest route.That is why I ordered arp You very rarely here of a stud breaking or a hg blowing if the arp are done right.I plan on tapping my block you will have the head off so it would be no problem the bottom tap the block.

 

Both studs are good.... I have used both and personally prefer the ARP studs due to the ARP 2000 material. A1 uses 4340 where ARP uses the ARP 2000. Here is a descrition of the ARP 2000 material:

ARP 2000 An exclusive, hybrid-alloy developed to deliver superior strength and better fatigue properties. While 8740 and ARP2000 share similar characteristics – ARP2000 is capable of achieving clamp loads in the 215,000-220,000 psi range. ARP2000 is used widely in short track and drag racing as an up-grade from 8740 chrome moly in both steel and aluminum rods. Stress corrosion and hydrogen embrittlement are typically not a problem, providing care is taken during installation.

Doug