Tech Articles

Once Disrespected, The Chevy 305 Engine Looks To Be A RaceSaver

The Chevy 305 engine has become popular with racers from the drag strip to the sprint car circuit, with ready availability and many aftermarket upgrades.

The small block Chevy 305 engine made its debut in 1976, designed by General Motors as a small V-8 that would provide improved fuel economy, while also sharing design and components common to the popular 350 engine to help reduce production costs. The engine shared the same 3.480″ stroke of the 350, but featured a smaller 3.736″ cylinder bore and a lighter crankshaft for proper engine balancing. Produced until 1998, the 305 found its way into a wide variety of GM vehicles including the Camaro, Firebird, and Chevrolet/GMC pickup, just to name a few.

Dart Little M Chevy 305 engine block
Dart’s Little M 305 block is a popular base for RaceSaver Chevy 305 engines.

The Chevy 305 engine was very reliable when properly maintained, although premature camshaft failures due to poor quality control and a lack of performance tarnished the engine’s image. Although not recognized as a high-performance engine, versions including the L69 “High Output 5.0L” and LB9 “Tuned Port Injection 5.0L” were respectable street performers.

Although its reputation as a passenger car engine was compromised, the 305 has actually experienced some success on the race track. The engine is commonly found in the many third generation Camaros and Firebirds that populate NHRA’s Stock and Super Stock Eliminator drag racing classes. Several racers have eclipsed the 10-second elapsed time mark – impressive to say the least for such a small V-8 in a car that tips the scales at well over 3,000 lbs.

Skyrocketing costs helped create a home for the Chevy 305 engine in the ultra-competitive world of sprint car racing. Initially created in the 1980’s, the “Econo Sprint” was launched as an affordable, entry-level class for aspiring drivers. Many of the cars used distributors and carburetors to help keep them affordable. The intention of controlling costs was initially successful, however, subsequent rule changes and calls for increased performance led to costs getting out of hand.

Legendary sprint car tuner French Grimes saw that sprint car racing costs were spiraling out of control and knew that something needed to be done to save the sport. After thorough research, Grimes created the RaceSaver Sprint Series in 1997, a series dedicated to making sprint car racing truly affordable. After experiencing steady growth, the series has since grown to over 1,000 cars since its inception, and with it currently under IMCA sanction, the future certainly looks bright for 305-powered sprints.

Truly enforceable rules have been key in making the series successful. The center piece to making it work is the Chevy 305 engine topped with RaceSaver/Brodix spec cylinder heads. Each RaceSaver head is stamped with identification marks and registered serial numbers, and may not be modified in any way. Gauge dimensions are used to prevent the possibility of illegal runner or combustion chamber modifications, and strict valve and spring rules are in place. The heads may be purchased directly from RaceSaver or an authorized dealer.

The block must be a production 305 with intact casting numbers, or the new Dart “Little M 305″. The engine may have a maximum of 315.9 cu. in. with a 3.480″ stroke (+/-.020″) and a maximum bore of 3.801”. It must be fitted with flat-top pistons, 5.700″ long steel rods, a crankshaft that includes a minimum weight of 48 lbs., wet sump oiling system, chain-driven camshaft, and conventional water pump. 

A cast iron camshaft with a maximum .510″ intake/.535″ exhaust lift must be used in conjunction with solid, .842″ diameter lifters. Roller rockers are permitted, but they must be centered and retained with 3/8″ rocker studs. All engines are sealed by RaceSaver certified personnel with serial numbered seals before they are allowed to race, while a “hard card” is used to record the name, address, head serial numbers, seal serial numbers, and home region for each engine.

To keep costs under control, a wide variety of performance engine parts and/or labor operations are prohibited, including stud girdles, rev kits, valve train stabilizers, roller camshafts, roller cam bearings, bushed lifter bores, etc. All engine components must be constructed from ferrous materials only, eliminating the use of titanium, inconel, ceramics, DLC, and Nikasil. Only point-type magnetos or Kettering (Delco)-style inductive discharge ignitions are permitted. The engine must be fed via a naturally-aspirated, constant flow fuel injection and fueled with pure methanol that is subject to chemical analysis. Although the engines can be built for under $6,000.00, they have been dynoed at roughly 450 horsepower.

The winged cars have a minimum weight of 1,550 lbs. with driver and fire suppression system included, and are required to have a 80″-95″ wheelbase. Bleeders and cockpit-adjustable weight jacks, shocks, or wings are not permitted. Complete rules are available at www.racesaver.com.

A big factor in the success of the RaceSaver Sprint Series is that it combines sprint car racing that is not only competitive, but affordable with true, enforceable rules, a concept previously thought unattainable. And how ironic it is that the series has also given a home to the once disrespected Chevy 305, previously thought of as an under-performing V-8 that had a penchant for premature camshaft failures.

As a testament to its success and potential, the RaceSaver Sprint Car Series was acquired in 2016 by Roger Hadan, owner and promoter of Eagle Raceway in Eagle, Nebraska. Hadan has been running the RaceSaver series at Eagle Raceway since 2012 and draws 30+ cars for most events. After experiencing this success, Hadan obtained the rights to the name RaceSaver and took over all media related activities, sponsorships, and hard card applications, while continuing to sanction under the IMCA. He continues to not only uphold the RaceSaver tradition, but to grow the series as well. French Grimes still governs all rules, regulations, and tech related issues for the series.