NEW 525RLB CT525 Sealed Racing Long Block


  • Capable of 533 hp @ 6,600 rpm/477 lb.-ft. @ 5,200 rpm
  • Lightweight, High-RPM LS Power!
  • Forged Pistons
  • For Circle Track Racing only – NOT intended for street use
  • Comes with GM anti-tamper fasteners installed

Shipping is free, but there is a delivery fee for residential addresses.

Chevrolet 525RLB 6.2L Crate Engine

This 6.2L 525RLB long block is a high-revving racing-focused engine built to power oval track racers like super late model and modified racers. This engine is very similar to other LS offerings here at Karl Kustoms, but thanks to the racing oil pan, and coil-on-plug ignition, this powerhouse can produce 533 horsepower at 6,600RPM and 477 lb-feet of torque at 5,200RPM.

With its cast-aluminum block design and forged aluminum pistons, this engine offers the power of lightweight LS builds coupled with circle-track focused horsepower and revs. When compared to similar 6.2L LS applications, this powerhouse offers more than 100 extra horsepower and 100 extra torque over standard 6.2L street-focused LS3s, plus a big bump in redline. If you’d like to learn more about our crate engine program at Karl Kustoms, check out this page.

If you’re looking for a full crate motor, mechanical parts for your LS, or just finding the right parts for your custom build, the team at Karl Kustoms is happy to help. As part of a Chevrolet dealer here in Des Moines, Iowa, we know our GM hot-rod engines and the secrets to getting them running their best. Our team of in-house machinists and welders are happy to help you find the right fit for your project, racer, or hot rod. Give us a call at 888-955-3646, or you can check out our reviews here.

Weight 400 lbs

Prop65WARNING: These auto parts can expose you to chemicals including phthalates and lead. Installing or using these parts can expose you to other parts containing these chemicals and to engine exhaust, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to