In the current era of LS-swap madness, some are quick to forget that the early small-block Chevy owned the enthusiast aftermarket for decades. Since everyone wants LS engines, the traditional small-blocks are even less expensive than they used to be, if that’s even possible. It’s now super easy to get a nice 400-horse 350 like this one, with a 2-year warranty, from places like Ohio Speed Shops.
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How cool is that? It features double-drilled heads that will take early or later-model intake manifolds, and either center-bolt or perimeter-style valve covers. It will accept 6-inch to 8-inch harmonic balancers, and either staggered or straight pattern starters. Pretty much whatever small-block stuff you’ve got left over from all those years of projects, this engine can use them!
Official Release
OHIO SPEED SHOPS 400+ HORSEPOWER 350 CRATE ENGINE
Ohio Speed Shops’ new “604 Street Boss” engine delivers 405 horsepower and 406 lb.-ft. of torque. It is designed around the capabilities of its unique, lightweight aluminum cylinder heads that enable improved airflow at higher rpm ranges.
The cylinder head casting is based on the proven GM Fast Burn design, with large intake runners and 2.00-inch intake and 1.55-inch exhaust valves. Beehive-style valve springs deliver greater high rpm performance and durability. Their egg-shaped profiles have less reciprocating mass in motion, require less spring pressure for greater valve control and handle valvetrain stresses more efficiently. They allow the 604 Street Boss to rev higher to make the most of every cubic inch of air drawn through it. The heads are double-drilled to accept both traditional pre-’86 and later “Vortec” style intake manifolds. This is a great choice to power any small-block Chevy-urged muscle car!
The 604 Street Boss uses an aggressive hydraulic roller camshaft that supports the engine’s high-rpm airflow capability while maintaining excellent low-speed drivability. This engine also comes with a limited 2-year, 50,000-mile warranty.
Contact Ohio Speed Shops for more information: (330) 349-4930, www.ohiospeedshops.com.
Features:
- Accepts both standard pre-86 12-bolt and/or the newer Vortec design 8-bolt intake manifolds.
- Accepts both 4-bolt perimeter style and/or center-bolt valve covers.
- The narrow body self-aligning roller rocker arms are designed for use with most standard height OE valve covers.
- Accepts both short or long water pumps without modifications or spacers.
- Accepts 6” thru 8” external balance harmonic balancers.
- Accepts staggered or straight bolt pattern starters.
- Accepts standard side motor mounts or Tri-Five front motor mounts.
- Both cylinder heads have all the 3/8” bolt holes for mounting accessories.
- Priced at $5,789
After spending almost a decade in the aerospace industry, Scott Parkhurst chose to learn about racing engines by working in some of Southern California’s most respected engine shops. He took on the role of Tech Editor at Popular Hot Rodding magazine back in 1998, and was instrumental in the development of both the Engine Masters Challenge competition and Engine Masters Quarterly magazine. He was also the founding Editor of Street Thunder magazine and Author of the V8 Horsepower Performance Handbook before he arrived at Timeless Muscle.
