ARP HEAD STUD FIXING KITS
( £108.33 EXC VAT )
ARP conrod bolt kits are sold in engine sets for Cooper S, A-plus or 998 conrods - see choices above.
These are a direct replacement for the standard fixings. Replacing the standard conrod bolts is a must on any performance engine build.
Beware of poor quality copies available elsewhere online - these are the genuine ARP product.
See the tabs for extra information and torque settings.
What material are these bolts made from?
ARP2000, an alloy steel with a tensile strength of 220,000 PSI. ARP2000 is used widely in motorsport applications as an upgrade from 8740 chrome moly in both steel and aluminium rods. Stress corrosion and hydrogen embrittlement are typically not a problem, providing care is taken during installation.
Are ARP bolts re-usable?
Yes. As long as the fasteners have been installed and torqued correctly, and show no visible signs of damage, they can be re-used. If they show any signs of thread galling or corrosion, they should be replaced. In the case of rod bolts, if any of them have taken a permanent set and have stretched by 0.001” or longer, you should replace them immediately. We stock the ARP rod bolt stretch gauge for this purpose.
Do I need lube on my bolts or studs?
We recommend using the supplied ARP Ultra-Torque lube to ensure an even, accurate clamp load and to prevent thread galling. The lube should be used under the head of the bolt or the bearing surface of the nut and on the threads, unless a thread sealer is used.
What torque settings should I use?
3/8" fixings should be torqued to 55lb.ft and 11/32" A-plus to 35lb.ft, or preferably checked using an ARP rod bolt stretch gauge and stretched to 0.0065"-0.0070".
Cooper S and 998: