Brian Crower Connecting Rods for Honda K20/K24

Brian Crower Connecting Rods - Honda K20/K24

You're building a boosted K series and you need connecting rods that aren't going to bend or snap when you're making 400 wheel horsepower. Your stock rods are fine for 250-300 whp but past that, you're asking for trouble. The rod bolts stretch, the rod beam flexes, and eventually something breaks. Brian Crower forges these H-beam connecting rods from 4340 chromoly steel. They're built for turbo and supercharged K series motors making serious power. Brian Crower makes these rods in two power ratings: 350 HP and 500 HP. If you're building a mild turbo K making 350-400 whp, get the 350 HP rods. If you're building a high-horsepower K making 450-500+ whp or you're running aggressive boost and high RPM, get the 500 HP rods. Both versions come with ARP2000 rod bolts that don't stretch like stock hardware. These rods work for K20A2, K20Z1, K20Z3, K24A1, K24A2, K24A4, and K24A8 motors.

Here's Why Stock Rods Fail on Boosted K Motors

Your stock K series connecting rods are powdered metal. Honda sinters metal powder into the rod shape and then machines it. That process is cheap to manufacture and the rods work fine for stock power levels. But powdered metal rods are brittle. When you add boost and you're making 350-400+ whp, cylinder pressures go way up. Every time the piston hits top dead center on the compression stroke, the connecting rod's getting compressed. Every time the piston's forced down on the power stroke, the rod's getting stretched. That constant loading and unloading stresses the rod. Powdered metal can't handle that stress like forged steel can. The rod bolts are the first thing to fail. Stock rod bolts stretch under high cylinder pressure. Once they stretch, they don't clamp the rod cap tight anymore. The rod cap shifts, the bearing spins, and you've got metal chunks in your oil pan. Even if the bolts hold, the rod beam itself can bend or crack. We've seen stock K series rods bend at 400 whp and snap completely at 450+ whp. Don't wait for that to happen.

H-Beam Rods Are Stronger and Lighter

Brian Crower forges these rods from 4340 chromoly steel. Forging compresses the grain structure of the metal and makes it way stronger than cast or powdered metal. The H-beam design means the rod's cross-section looks like an H when you look at it from the end. That H shape gives you maximum strength with minimum weight. The beam's thick where it needs to be strong (at the big end and small end) and it's narrower in the middle to save weight. Less rotating mass means the motor revs faster and you're not wasting energy accelerating heavy rods up and down. Brian Crower CNC machines every rod to tight tolerances so the weight's matched within a few grams across the set. Matched weight matters because if one rod's heavier than the others, you've got an imbalance and the motor's going to vibrate.

ARP2000 Rod Bolts Don't Stretch

The rod bolts are what hold the rod cap to the rod beam. Stock rod bolts are basic fasteners. They're torqued to a specific value and they work fine for stock power. Under high cylinder pressure, they stretch. Once they stretch, they lose clamping force. The rod cap can shift and the bearing can spin. ARP2000 rod bolts are made from a proprietary alloy that's way stronger than stock hardware. They're heat-treated and they don't stretch under high loads. When you torque ARP2000 bolts to spec, they maintain clamping force even when you're making big power. You're not retorquing them after every track day and you're not worrying about them letting go. Brian Crower includes ARP2000 bolts with these rods. Don't reuse your stock rod bolts. Don't use cheap aftermarket bolts. Use the ARP hardware that comes with the rods.

Pick the Right Power Rating for Your Build

Brian Crower makes these rods in two versions: 350 HP and 500 HP. The 350 HP rods are designed for street and street/track K series motors making up to around 400 whp. If you're running a K20 or K24 with a small turbo making 350-400 whp on pump gas or E85, the 350 HP rods handle it. The 500 HP rods are designed for high-horsepower builds making 450-500+ whp. If you're running a big turbo, high boost, and aggressive tuning, get the 500 HP rods. The main difference between the two is the rod beam thickness and the overall strength rating. Both use the same ARP2000 hardware. Both are forged from 4340 chromoly. The 500 HP rods are just built heavier to handle more power. Don't cheap out and buy the 350 HP rods if you're planning to make 500 whp later. Buy the right rods for your power goal now.

K20 vs. K24 Rod Length

Brian Crower makes these rods in K20 length and K24 length. The K20 rod is shorter. The K24 rod is longer. If you're building a K20A2, K20Z1, or K20Z3 motor, you need K20 rods. If you're building a K24A1, K24A2, K24A4, or K24A8 motor, you need K24 rods. If you're building a Frankenstein motor with a K24 block and a K20 head, you need K24 rods because the rod length is determined by the block, not the head. Don't order the wrong rod length. Measure your stroke and confirm which rod length you need before you order. Wrong rod length means the piston's either hitting the head or it's not coming up high enough and your compression ratio's off.

What You Get

• Brian Crower H-beam connecting rods for K20/K24 motors (set of 4)
• Forged from 4340 chromoly steel
• CNC machined to tight tolerances
• Weight-matched set (all rods within a few grams of each other)
• ARP2000 rod bolts included
• Aluminum/silicon/bronze pin bushings
• Micropolished surface finish
• Available in 350 HP or 500 HP ratings
• Available in K20 or K24 rod lengths

Fits These Engines

• K20A2
• K20Z1, K20Z3
• K24A1, K24A2, K24A4, K24A8

Note: Order the correct rod length for your motor - K20 rods for K20 motors, K24 rods for K24 motors. If you're building a K24 block with a K20 head, you need K24 rods. Order the correct power rating for your build - 350 HP rods for up to ~400 whp, 500 HP rods for 450+ whp. When you're assembling the motor, follow the torque specs for ARP2000 hardware. Don't use the stock torque spec. ARP provides specific torque values and you need to follow them. Use ARP Ultra-Torque assembly lube on the threads and under the bolt heads. Have your machine shop resize the rod big ends after installing the ARP bolts - the bolts clamp tighter than stock hardware and the big end bore diameter will shrink slightly.