Description:

As shown in the video below, our flex-fuel, 3.8L Whipple-supercharged, 427ci LS delivered an awe-inspiring 1,427 horsepower (6,700 rpm) and 1,284 lb-ft of torque (4,800 rpm) on E85. The dyno sheets are in the photoset. The pump gas version looks identical and pushes out 1,335 horsepower (dyno chart in photoset).

Whipple superchargers are known for their explosive throttle response which comes from their internal bypass, extreme low-end torque and no lag. Their internal liquid-to-air intercooler eliminates the need to fabricate external systems which can add considerable expense. The internal bypass also allows the engine to run naturally aspirated (under vacuum) when under light load conditions (blog on twin screw internal bypass & intercooling). This new 3.8L model features Whipple's latest rotor design and an upgraded intercooler. That means more boost and less heat.

This engine in the video was built to run either pump gas or E85, and comes complete as shown. It is dyno-tested and ready to run using the tune from its dyno session loaded on the included Holley Terminator X-Max. This ECU also doubles as a trans controller for your automatic transmission. The hydraulic-roller cam does not require periodic valve lash adjustment. 

We build this engine in three flavors: pump gas only, flex fuel or dedicated E85. The primary difference between a pump gas and flex fuel design is fuel injector sizing. We switch from dish to flat top pistons for E85-only to take advantage of its higher octane (usually 105). The higher compresssion will take us up to around 1,475 horsepower.

Needless to say, this kind of power needs a stout build. This is a parts lineup that delivers strength:

• Dart LS Next SHP iron block with main stud upgrade
• Callies Apex crank and Ultra Enforcer rods
• Custom Diamond Race Series pistons
• Custom COMP hydraulic roller cam and BSR shaft rockers
• All Pro heads that have been CNC machined by us from 12-4 reinforced porter castings

The custom serpentine system delivers both performance and looks. The billet bracketry has the strength not to flex under load. It comes with a 225 amp alternator which can be upgraded to 300 amps. A remote power steering reservoir is standard. It can be switched to a pump with fittings for use with Hydra-Tech hyraulic brake boosters.

Since we mentioned looks, this engine sports a black anodized finish with a diamond cut serpentine pulleys. The supercharger, billet valve covers and serpentine can all be ordered with a polish finish or mixed and matched. Building a show car? Ask us about custom finishes.

Other Available Options

Pump gas, flex-fuel and alcohol only versions

Oiling System: A Holley Retrofit oil pan is standard as it is ideal for most restomod LS swaps. A Dailey Engineeering 3-stage dry sump oiling system is highly recommended for competitive applications (blog on benefits). A GM F-body baffled pan is also available.

Engine Management / Instrumentation. Don't need a transmission controller? Swap out the standard Holley Terminator X-Max for the lower cost Terminator X. Either Holley system is compatible with their Digital Dash line which can replace or augment your vehicle's instrument panel. The more feature-rich and robust FuelTech FT550 and FT600 engine management systems are great alternatives for racing and marine applications. The units feature an integrated touchscreen display that is IP67 rated for marine environments. Their new FT700 unit is an entirely new generation of vehicle control, data collection and connectivity. FuelTech has also become highly regarded for its global tech support.

Engine Block: The Dart iron block can be upgraded to a Dart or LSR aluminum block which can also be further customized. Switching to aluminum delivers a 100 lb weight reduction which can significanly enhance vehicle handling and performance.  Aluminum also cools better than iron.

4L80E Custom Transmission: We have been working for many years with Hughes Performance who build transmissions for us that are intended to be paired with our engine builds including this one.

As mentoned previously, this is a Plug & Play package.  Pricing includes all standard options mentioned above plus pallet, box and engine cradle which can be returned for credit. Shipping is charged separately. Please call us at 815-725-2727 with any questions and for pricing with the option set that best fits your needs.