Engine of the Week is presented by
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Growing up with his eyes glued to automotive magazines, as so many of us did, Ramiro Ramirez knew he wanted a career dealing with high-performance engines. Inspired by Sonny Leonard of Sonny’s Racing Engines, Andy Jensen of Jensen’s Engine Technologies and Steve Morris of Steve Morris Engines, Ramiro began his journey to learning how to build engines.

Today, his business, Fatboys Racing Engines located in Monterrey, Nuevo Leon, Mexico, has been building engines for 16 years. With a focus on naturally aspirated engines and nitrous engines, Fatboys has recently started to offer forced induction builds as well. The shop’s engine builds are most commonly used for street/strip, drag racing and sand drag applications.
One of the shop’s engine builds is a 502 cid LS engine for a street/strip application that the shop put into a 2010 Chevy Silverado single cab truck.

“It’s for daily use and the track,” Ramirez says. “I like to go fast on weekends with friends and family.”
The engine build started with an RHS aluminum tall-deck block that features a 4.170˝ bore and a 4.600˝ stroke.

The heads for the LS build are Mast Black Label 305s. Fatboys Racing Engines used a Jesel valvetrain, a solid roller Cam Motion camshaft with low lash, a Marcella Manifolds intake, and a Nick Williams 112 mm throttle body.
Other parts in the LS build are a billet crankshaft, I-beam connecting rods, Wiseco coated pistons, Clevite coated main and rod bearings, a Melling high-pressure oil pump, a single timing chain, ARP hardware, an ATI super damper, Fuel Injector Clinic injectors, and Bow Tie valve covers.

“The modifications that have helped me a lot are the camshaft by Cam Motion and the cylinder head porting and polishing done by Greg Good in Houston,” Ramirez says.
With the engine all buttoned up, Ramiro says the final product boasts a 12.5:1 compression and cranks out 870 horsepower and 700 ft.-lbs. of torque at 7,100 rpm. Time for a fun day at the track!

Engine of the Week is sponsored by PennGrade Motor Oil, Elring – Das Original and Scat Crankshafts. If you have an engine you’d like to highlight in this series, please email Engine Builder Editor, Greg Jones at [email protected].