Photos Courtesy of ARP
We’ll get right to the point on this one. We’re not featuring some gee-whiz new product in this month’s tech review. Instead, we are taking a look at one company that probably makes the best components of its kind in the racing and performance industry. That company would be Automotive Racing Products (ARP). They do one thing and do it well, and that happens to be fasteners. This includes nuts, bolts, studs, washers and a whole host of other bits and pieces that hold engines and other car-related components together.
So if we’re not talking about any specific part here then what are we doing? We are, in fact, going to discuss how to install these critical pieces of the automotive puzzle. As the title states: “Read the instructions!” And in the case of ARP’s excellent line of fasteners of all types, that advice couldn’t be more important.
If you simply look at a fastener as a tool, it becomes apparent that improper use can deliver less than desirable results when using said tool. Following that line of thinking, it should come as no surprise that not following a fastener’s instructions could lead to unwanted issues, not the least of which may be stripped threads, improper clamping or tightening, or even broken or seized fasteners. Oftentimes, the tech staff at ARP gets questions regarding fastener failure or issues with installation, and oftentimes these unexpected results are from simply not following the included instructions.
While ARP fasteners of all kinds are important, our main focus here is going to be correctly tightening cylinder-head bolts and studs. Popular examples include Ford Coyote 5.0 and GM LS applications. And with some variation, this information is relevant for any engine that ARP covers.
ARP spokesman Chris Raschke also told us of one recent update to ARP head- bolt and stud kits for various applications. “We’ve made some improvements to the washers on Coyote and LS kits,” said Chris. “We have also been focusing on the instructions. We wanted to make improvements there as well.”
While there are similarities in instruction sheets for many cylinder-head applications, keep in mind there are also notable differences as well. For example, cylinder-head torque sequences are different with such variances as the Ford Coyote having 10 bolts and the GM LS having 15.
Finally for good measure, we are going to recite installation instructions below for a Ford Coyote application. Note also that we included a few ARP website links below that are very helpful. The ARP site is loaded with tons of super useful technical information to help you get the most out of any ARP individual fastener or inclusive installation kit.
Installation Method for Head Stud Kits
PN: 256-4702, Application: Ford 5.0-liter Coyote V8 (2011-2012) M12
- Inspect all hardware prior to installation. Look for obvious defects or shipping damages. Please call 800-826-3045 with any questions or issues.
- To ensure proper thread engagement and accurate torque readings, clean all threads in the block. Chase if necessary with ARP Thread Chaser, PN 912-0008 (M12 X 1.75)
- Clean the spot faces on the cylinder head where the washer seats, use of solvent or brake/carb cleaner is recommended.
- Install the head gasket and cylinder head.
- Screw the studs into the block hand tight, do not apply torque. The hex broach in the end of the stud is designed to assist with only installing/removing the studs from the block, not for applying torque.
- Then, using a clean, dry rag remove all oil from both sides of each washer. The cylinder head and washer mating surfaces must be free of oil/grease/lubricant. Failure to keep these surfaces dry may result in inconsistent preloads.
- Place the washers over the studs and on to the dry, clean spot faces of the cylinder head.
- Lubricate the stud threads and bottom of the nuts with ARP Ultra-Torque Fastener Assembly Lubricant. Then install the nuts onto the studs and tighten hand tight.
- Following the manufacturers recommended torque sequence, shown below, torque the nuts per steps 1-4
1- Tighten nuts 1 through 10 (12mm) to 40 ft-lbs.
2- Tighten nuts 1 through 10 (12mm) to 80 ft-lbs.
3- Tighten nuts 1 through 10 (12mm) to 125 ft-lbs.
The proper sequence for Coyote, LS or any other engine is included in ARP’s instruction sheets.