Featured Parts
Transmission Swap Blocks
Engine Swap Blocks
Engine swaps, transmission swaps, and custom fabrication projects all have one thing in common: the more accurately you can mock up the build before final assembly, the smoother the project goes. That's exactly why G Force Performance Products developed its growing lineup of Swap Block™ engine and transmission mock up tools as part of the company's Garage Essentials collection.
The Garage Essentials product line was created to give builders practical tools that make fabrication, installation, storage, and shop work more efficient. Alongside products like engine lift plates, transmission dollies, differential dollies, engine stands, and shop organization tools, G Force Swap Blocks provide a smarter way to plan and execute engine and transmission swaps.
Rather than repeatedly lifting a complete drivetrain in and out of a vehicle to check fitment, a Swap Block allows builders to establish motor mount location, crossmember position, driveline angle, transmission tunnel clearance, and accessory fitment using a lightweight steel mock up that accurately replicates the dimensions and mounting points of the real component.
Whether you're building an LS-powered muscle car, fitting a Godzilla engine into a Mustang, planning a Cummins conversion, or fabricating a custom transmission crossmember, Swap Blocks represent the same philosophy found throughout the G Force Garage Essentials lineup: save time, improve accuracy, and make complex projects easier to complete.
Everything you need to know about G Force Swap Block™ engine and transmission mock up blocks, what they are, why serious builders use them, and which one fits your swap.
In This Guide
If you've ever done a serious engine swap, you already know the drill: crane the engine in, realize the motor mount perch is off by a quarter-inch, crane it back out, grind something, crane it in again. Repeat until your back gives out or your fenders are scuffed.
The G Force Swap Block™ is a lightweight, precision-cut steel mock up block that replicates the exact external dimensions and mounting points of a real engine or transmission.
You use it to dial in motor mount placement, crossmember fabrication, header clearance, oil pan fitment, and driveline angle before the actual powertrain ever leaves the engine stand.
Think of it as a full-scale jig of your engine or transmission. Every critical bolt hole, mounting face, and interface is there. What isn't there is the 400 to 800 pounds of engine or transmission weight you'd otherwise be moving around.
G Force Swap Blocks are designed for:
Precision Motor Mount Placement
Dial in crossmember and motor mount geometry before welding.
Weld-Safe Steel Construction
Unlike foam, G Force Swap Blocks handle welding heat.
Lightweight Design
Move the block in and out of the engine bay by hand.
Accessory Mock-Up Capability
Check oil pan, header, water pump, and intake clearances.
Ships Flat, Easily Stored
Arrives disassembled and stores easily.
Made in the USA
CNC laser-cut and manufactured domestically.
The old-school approach was a foam dummy block cut to roughly resemble an engine.
G Force took a different approach with precision-cut steel and a patent-pending tab-and-slot assembly system.
Foam melts.
Foam cannot tolerate welding heat. Steel allows you to tack mounts directly to the block for accurate fitment.
Foam drifts.
Foam lacks dimensional stability. Steel maintains geometry under torque, weight, and fabrication work.
Foam is one-and-done.
Oil, solvents, and handling damage foam. Steel survives repeated use.
If you're fabricating custom mounts, crossmembers, or brackets, steel is the right tool. Foam is for rough positioning. Steel is for building.
G Force developed a tab-and-slot construction method to improve accuracy and rigidity.
G Force currently offers engine Swap Blocks for many of the most popular swap platforms.
Available Engine Platforms
|
Engine |
Applications |
|
LS (Gen III/IV) |
4.8L, 5.3L, 6.0L, 6.2L |
|
LT (Gen V) |
LT1, LT4, LT5 |
|
Small Block Chevy |
|
|
Big Block Chevy |
|
|
5.7L, 6.1L, 6.4L, 392 |
|
|
Ford Godzilla 7.3L |
Ford pushrod V8 |
|
2011+ Mustang and F-150 |
|
|
3.9L diesel |
|
|
5.9L diesel |
|
|
GM diesel |
|
|
Honda K-series |
G Force offers bundles pairing Swap Blocks with DIY motor mount kits and lift plates for LS, LT, Godzilla, and Hemi applications.
Transmission Swap Blocks allow builders to verify:
|
Transmission |
Applications |
|
GM 6-speed automatic |
|
|
Tremec 6-speed manual |
|
|
GM heavy-duty automatic |
|
|
Ford 6-speed automatic |
|
|
ZF 8-speed automatic |
|
|
GM 10-speed automatic |
|
|
GM 4-speed automatic |
|
|
GM 3-speed heavy-duty automatic |
One of G Force's most popular setups combines the LS Swap Block with the 6L80E/6L90E Transmission Swap Block, allowing builders to mock up:
during a single mock-up session.
What is a G Force Swap Block?
A lightweight steel mock-up block that replicates the external geometry and mounting points of an engine or transmission.
Are G Force Swap Blocks steel or foam?
Steel. They are CNC laser-cut from steel and designed to withstand fabrication work and welding heat.
Which engine platforms are available?
Which transmission platforms are available?
Can I fabricate custom motor mounts with a Swap Block?
Yes. That's one of the primary uses. Builders can position and tack mounts while using the mock-up block, then complete final welding afterward.
Can I test-fit headers and oil pans?
Yes. Swap Blocks allow you to bolt on actual components to verify chassis clearances before final assembly.
Do they come assembled?
No. They ship flat and assemble using the tab-and-slot system.
Will the TR6060 Swap Block work for Hemi or Ford applications?
No. The TR6060 version is designed specifically around the GM bellhousing pattern.
Where are G Force Swap Blocks made?
They are manufactured in the United States from CNC laser-cut steel.
Explore the complete Garage Essentials collection at Crossmembers.com to find fabrication tools, lifting equipment, storage solutions, and mock up products designed specifically for engine swaps and custom vehicle builds
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