When Should You Upgrade Your 4x4 Chassis? Complete Walk-Through
Jason breaks down a complete custom 4x4 chassis build for a Gen 2 Bronco—explaining when you should upgrade your chassis, what makes FFG's different, and walking through every component from the 700HP Whipple Coyote setup to the billet steering and suspension.
This isn't your average 4x4 chassis. FFG engineers these with 3/16 plate steel, laser-cut and welded for maximum rigidity. The problem with stock 67-79 4x4 frames is they're built for 1970s technology—narrower rear tires, older geometry, and they struggle with modern power. If you want your classic truck to handle like a modern F-150 or F-250, this is how you get there.
This customer ordered this chassis for his 78-79 Bronco and spec'd it for a Gen 3 Coyote with a Whipple supercharger. FFG helped install the supercharger and Power by the Hour front runner system—everything's dialed in tight with proper clearances. Jason walks through why a 3L Whipple is the sweet spot for daily driving (you can hit 800-900 HP if you want, but 700 is plenty), how pulley size affects boost, and why the steering setup uses off-road grade RPM billet components instead of flex-prone alternatives.
FFG worked with our engineers and Porterbuilt to design this chassis from the ground up. The chassis comes with Redhead steering that's hydroboost-ready, Locked Off-Road coilovers with remote reservoirs, and upgraded 16-inch rotors with massive calipers. Dual 3-inch stainless exhaust runs all the way back through resonators and Magnaflow mufflers. The 30-gallon side-fill fuel tank has a GT500 pump built in to handle the supercharger, and Jason recommends adding a Vapor Trapper to keep your garage from smelling like fuel.
Whether you're a shop trying to speed up builds or a DIY guy in your garage, this chassis simplifies everything. Fuel lines and brake lines are pre-ran, it's ready for body drop, and you're not fighting old technology trying to handle modern horsepower. Jason even shows the integrated tie-down hooks FFG built in—small details that make transport and strapping way easier.
If you're building a 67-79 F-100 4x4, a Gen 2 Bronco, or any classic 4x4 truck and wondering if a custom chassis is worth it, this is the breakdown you need.
Learn more about FFG chassis options: https://fatfender.com/pages/ffgchassis
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BUILD SPECS:
1978-79 Gen 2 Ford Bronco Chassis
Gen 3 Coyote 5.0L V8
Whipple 3L Supercharger (700+ HP, 3.875 pulley)
10R80 10-speed transmission
Atlas transfer case (in-cab shifter)
Redhead steering box (hydroboost-ready)
RPM billet tie rods and track bar
16" rotors with upgraded calipers
Locked Off-Road coilovers with remote reservoirs
Dual 3" stainless exhaust, Magnaflow mufflers
30-gallon side-fill fuel tank, GT500 pump
3/16 plate steel construction
Four-link front, triangulated or four-link rear options
Integrated tie-down hooks
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