Building a Roll Cage for a 550 HP Twin Tesla Suzuki Carry

TL;DR: Andy Didorosi's Sendpai project is a 1996 Suzuki Carry with two Tesla drive units making 550 combined horsepower. This episode covers building a custom roll cage by hand using a Rogue Fab M605 tube bender, including the inevitable failures from spring back and misalignment. The main takeaway for anyone building on a kei platform: prototyping with PVC pipe before cutting expensive DOM tubing saves real money.

A 660cc three cylinder kei truck making 550 horsepower is going to need a cage. That much is obvious. What is less obvious is how you actually fit a roll cage inside a cab that measures roughly 1,200mm wide, where the tolerances between "fits perfectly" and "does not fit at all" are measured in single digit millimeters. Andy Didorosi's Sendpai project, a 1996 Suzuki Carry stuffed with dual Tesla large drive units, is the most absurd kei truck build happening right now, and the cage fabrication episode is a masterclass in what happens when ambition meets the physical constraints of a vehicle designed to haul daikon radishes.

Why the Sendpai Needs a Cage

The Sendpai is not a farm truck. Two Tesla LDUs produce roughly 275 horsepower each, for a combined 550 HP going through an all wheel drive system. For context, that puts this Carry in the same power bracket as a MotorTrend tested Porsche 911 Carrera GTS, except the Porsche weighs 3,400 pounds and the Carry weighs about 1,600 pounds before the swap. The power to weight ratio is genuinely dangerous, and a roll cage is not a stylistic choice. It is the only thing standing between the driver and the laws of physics when 550 horsepower meets a wheelbase shorter than most couches.

Tesla large drive units have become the LS swap of the EV world. As InsideEVs reported, a refurbished LDU costs around $4,000 with a warranty, or as little as $500 from a salvage yard. The challenge with stuffing two into a kei truck is not the motors. It is everything else: batteries, cooling, wiring, and critically, the structural reinforcement needed to keep the cab intact under forces it was never designed to handle.

Prototyping with PVC Before Steel

The smartest move in the entire build happens before anyone touches metal. Andy and fabricator Chris use PVC pipe and tubing protractors to prototype the cage layout, testing fitment and bend angles at a fraction of the cost. A stick of 1.75 inch DOM tubing runs $50 to $80 depending on wall thickness and length. A stick of PVC costs a few dollars. When you are working without CAD or a jig, in a cab that does not match any existing cage kit on the market, the PVC prototyping step is the difference between a $200 mistake and a $2 one.

This approach is Rogue Fabrication's own recommendation for first time cage builders. Their M605 tube bender, which Andy and Chris use throughout the build, is a manual rotary draw bender that runs around $1,800 for the base unit. It handles 1.5 to 2 inch tubing and produces repeatable bends, but it does not compensate for the operator. You still need to understand spring back, center line alignment, and how the protractor thickness affects your measurements.

Spring Back Will Humble You

The first real bend goes well. The second one does not. After bending the main hoop, the team discovers that spring back, the tendency of metal tubing to partially unbend after the force is removed, has produced a hoop that is too wide for the Carry's cab. The hoop looks right on paper but sits proud of the B pillars by enough to be unusable. As PickupTruckTalk's fabrication guide notes, not accounting for spring back is one of the most common mistakes in roll cage construction.

The fix involves two lessons that apply to anyone bending tubing for a kei truck project. First, always mark a center line down the length of the tube before bending. The center line lets you verify rotational alignment at every stage, and without it, you are guessing whether the tube has twisted during the bend. Second, account for the physical thickness of your protractor when transferring measurements. The protractor sits on the outside of the tube, so measurements taken from its face are offset from the tube's actual center line by a few millimeters. In a full size truck cab, that offset might not matter. In a Suzuki Carry cab, those millimeters are the entire margin.

The Second Attempt Fits

Armed with lessons from the failed hoop, Andy and Chris cut a new piece of DOM tubing, mark a precise center line with a paint marker, and rebend the main hoop from scratch. The second hoop drops into the cab and sits flush against the B pillars on both sides. The fit is tight enough that the hoop needs to be angled in through the windshield opening, which tells you exactly how little clearance exists between the cage and the cab structure.

This is the reality of fabricating anything custom for a kei truck. There are no off the shelf cage kits for a Carry. No CAD files on forums. Every measurement is taken by hand, every bend is a judgment call, and every mistake means buying another $60 piece of tubing. The parts sourcing guide covers options for DOM tubing and fabrication supplies, and Oiwa Garage stocks structural accessories for kei trucks. The community on r/keitruck has been following the Sendpai build with predictable enthusiasm.

What the Sendpai Means for the Kei Truck Scene

The Sendpai is a halo car for Didorosi's startup company Mutiny, and it serves that purpose well. But it also represents a broader trend in the kei truck community: people are moving beyond bolt on lift kits and LED light bars into serious, ground up fabrication. The off road mods guide covers the more accessible end of kei truck modification, but projects like the Sendpai show where the ceiling actually is. If you can fit two Tesla drive units and a full ARA spec rally cage into a vehicle that was designed to navigate Japanese farm roads at 40 km/h, the platform is more capable than most people assume.

EV swaps into kei trucks are still rare, but the concept is gaining traction. A Subaru Sambar EV conversion recently made the rounds on r/minitrucks, and Ludwig Ahgren's well documented Subaru Sambar conversion through Legacy EV in Arizona proved the concept is viable even for builds that prioritize daily drivability over outright horsepower. For most kei truck owners, the existing 660cc engine is plenty, but for anyone who has looked at their Honda Acty or Daihatsu Hijet and thought "what if," the Sendpai is proof that the platform can handle it.

Future episodes of the build will cover the rear stays and door bars that complete the cage, plus the electrical integration needed to make 550 horsepower controllable. For now, the main hoop is in, the cab is partially cut, and Andy Didorosi has a kei truck with more horsepower per pound than a Bugatti Veyron. Check your state's registration requirements before planning anything this ambitious, and browse the dealer directory if you need a clean Carry to start your own build.