ARP 134-5202 Main Cap Bolt Kit – Black Oxide

Part #: 134-5202 | Price: $61.35

Direct Fit: Small Block Chevy (262-400ci) with large journal cranks and 4-bolt main caps. If you’re building a 350 or a 400, these are your bolts.

You know that sinking feeling when you torque a stock bolt and wonder if it’s really up to the task? Stop wondering. This ARP 134-5202 kit replaces those factory fasteners with something you can trust.

These aren’t just shiny bolts. They’re 8740 chromoly steel, heat-treated to a consistent 180,000 PSI tensile strength. That means they clamp hard and stay tight. We use them in our own shop builds because they prevent main cap walk, which is a death sentence for bearings and crankshafts.

ARP does the little things right so you don’t have to worry. The threads are rolled after heat treat. It’s a more expensive process that work-hardens the threads, making them significantly stronger and more resistant to stripping compared to cut threads. The under-head radius is precision-machined to ensure even load distribution and accurate torque readings every time you put a wrench on them.

At just over sixty bucks, this is one of the most cost-effective insurance policies you can buy for your Chevy small block. Why risk a $2000+ rotating assembly on marginal fasteners? For a street performance build, a turbo motor, or a nitrous engine, this kit is the standard. OEM-style black oxide finish keeps them looking correct and provides light corrosion resistance.

The Bottom Line: You’re buying proven strength, not marketing hype. This specific kit has been the go-to for decades for a reason. It works. Add it to your cart, install it with confidence, and never look back.

Autopartssupplyusa.com: We stock the parts that work. This ARP kit ships from our warehouse, ready to go to work in your garage.