Even as LS engine builds come across as more commonplace and routine, Horace Mast and his crew at Mast Motorsports find new ways to breathe fresh air into the Gen III and IV engines.

The team’s latest creation draws inspiration from vintage racing. Mast took its Black Label LS3 416 cubic inch crate engine and fitted Hilborn Fuel Injection‘s LS series Chevy EFI setup on top of the beast. 

“Our customer wanted this combination, but he also wanted it tame enough for the street, which brings it’s own set of problems. Hilborn injection systems love to work at full on or full off, so making it streetable is a task,” explains Mast crewmember Chris Durrett. “We set the engine up to be drive-by-wire with our M-120 dual wide-band controller.”

While the LS3 was mild mannered enough for a school mom’s car-pool vehicle, it’s now producing 630 horsepower under the vintage guise of a Black Label LS3 crate engine.  

Mast Motorsport’s Black Label LS3 Engine Specs:

• Type: LS3 6.8L
• Displacement: 416 Cubic Inches
• Compression Ratio: 11.2:1
• Bore x Stroke: 4.070 x 4.000
• Rev Limit: 7000 RPM
• Crank: Callies Forged
• Rods: Callies H-Beam
• Pistons: Mahle Motorsports
• Cam: Mast Custom 3-Bolt Core Cam
• Heads: Mast 12 Degree CNC LS3 Heads
• Valve Springs: Mast Nitrided Beehive
• Part Number: 111-223

Hilborn Fuel Injection System:

• Part Name: LS Series Chevy Electronic Fuel Injector
• Application: LS engines with any deck height, LS1, L92, or LS7 heads
• Bore Size: 2-3/16″, 2-7/16″, 2-1/2″, 2-5/8″
• Heat-treated aluminum casting 
• Cad-plated steel ram tubes 
• Fully assembled with shafts, butterflies, linkage, fuel rails, mounted TPS with connector and vacuum kit