Chevrolet Performance has unveiled the new 525 RLB racing crate engine, a long-block assembly based on the CT525 that is well-suited for spec-based off-road competition. The 525 RLB is designed as a cost-effective performance solution, and was developed with input from established motorsport groups. The new LS-based 525 RLB engine made one of its first public appearances during the 2023 BFGoodrich Tires Mint 400.
The LS-based 525 RLB chucks out 533 horsepower and 477 pound-feet of torque when topped by a four-barrel carburetor and intake manifold, per the Chevrolet Performance catalog. Highlight specs include forged pistons, heavy-duty connecting rod bolts, and LS3 rectangular-port cylinder heads, as well as a coil-in-plug ignition system, SFI-certified balancer, and six-quart racing oil pan. Customers will need to add their own induction and ignition system.
The 525 RLB was developed in collaboration with Robert King from Klein Engines, who boasts a long history in motorsport and racing engine development across a multitude of disciplines, from dirt and pavement circle track, to IndyCar, to sand rails, to desert racing, and even boats. Development of the 525 RLB was done with the simplification in mind, in the hope that racers would more be able to more easily navigate engine regulations across multiple racing classes.
King works closely with veteran road racer Jeff James, a Chevrolet Performance parts and performance specialist out of Westlake Village, California. James found that there was an opportunity to build on the CT525 for racing applications and provide a simplified package that could satisfy multiple sanctioning bodies.
“Let’s give them a more durable package that is more cost-effective and is more verifiable,” James says. “Each sanctioning body can package their rules [their own way], but if this guy wants to come run with this other group, he’s legal without having to make a bunch of engine changes, or having to take this motor out and put this open motor in or something like that.”