Toroidal (Spare Wheel) Tank vs. Cylindrical LPG Tank: Which Is Right for Your Vehicle?
When installing an LPG autogas conversion kit, selecting the right tank style depends on your vehicle's cargo space requirements, desired driving range, and chassis layout.

Toroidal (Donut / Spare Wheel Well) Tanks
Toroidal tanks are engineered to fit directly into the vehicle’s spare wheel compartment under the trunk floor mat.
Key Advantage: 100% trunk space retention; completely hidden from view.
Best For: Passenger sedans, hatchbacks, and crossovers used for daily commuting.
Capacity Range: Typically 35 to 70 liters (gross capacity).
Cylindrical Tanks
Cylindrical tanks are traditional tube-style tanks mounted across the trunk floor behind the rear passenger seats or under light commercial truck beds.
Key Advantage: Larger storage capacities for extended highway driving ranges.
Best For: Commercial vans, pickups, taxis, and long-distance fleet vehicles.
Capacity Range: Typically 60 to 120+ liters.

Frequently Asked Questions
Which LPG tank is better for saving trunk space?
Toroidal (donut) tanks are the best option for preserving trunk space. They fit neatly into the spare wheel well under the trunk floor, leaving 100% of the usable boot area free for luggage.
Which tank gives a longer driving range: Toroidal or Cylindrical?
Cylindrical tanks generally offer a higher capacity (up to 120+ liters compared to 35-70 liters for toroidal tanks), making them ideal for long-distance drivers and heavy commercial use.