MED 1.5 LDX ROCKERS
( £258.33 EXC VAT )
This kit is available for either nine or 11-stud applications - please see the dropdown menu above.
ARP fixings are an essential upgrade over standard studs, not to be confused with poor quality aftermarket replacements. Be particularly wary of imitation ARP kits online - these are the genuine article.
Check the other tabs for tech info and instructions.
What material are these studs 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 and studs 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.
Do the head studs only go in hand tight?
Yes, cylinder head studs are installed only hand tight. Other than the use of an allen wrench on the hex broached into the end of the stud (to ease installation, not to apply torque), use no tools to seat them in the block. However, it is extremely important to ensure that the studs are fully bottomed out in the hole in the block and not hung up on damaged or corroded threads in the block preventing the stud from being fully seated. This is often indicated when the stud threads extend past the deck surface.
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.
Do I install my studs into the block first?
After test fitting the studs in the block, it is generally easier to remove the studs, put the head gasket and head on the block and install the studs. This will reduce the possibility of damaging the upper threads of the stud and scraping the cylinder mounting holes.
Does the chamfer on the inside diameter of the washer go up or down?
The chamfered side of the washer goes up, towards the head of the bolt. The chamfer is there to create clearance for the radius between the bolt shank and the bolt head.
I have heard that the black oxide bolts and studs will eventually rust, is this true?
Yes, the bolts or studs will rust. Black oxide is a conversion coating formed by a chemical reaction with the iron in the metal to form an integral protective surface. It is not a permanent coating that has bonded to the surface of the fastener. The black oxide process is a short-term rust preventative only and any part exposed to the atmosphere will show signs of rust in a matter of days. Frequent application of oil to the part will increase corrosion resistance.
Please see below for ARP's fitting instructions. Our personal recommendation is to torque the head fixings down a little more to 50lb.ft.