Video: Mast Motorsport's LS3 Engine With Hilborn Injection

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

Factory Five Roots

While the Hilborn injection system didn’t pick up any more power than the standard Mast Motorsports Black Label LS3 package, “it picked up quite a bit on torque,” adds Durrett. “You could probably make more power if you went with a supercharger, but you have to admit the injection system on our pump gas LS3 is unique and cool.”

The engine will be installation in a Factory Five GTM body. “I believe this car will be in the Factory Five booth at this year’s SEMA show,” says Durrett.

If you see an interesting engine project at your local shop, let us know at [email protected]