Losi IMSA GROM GT3 Battery Upgrade: More Capacity in a Compact 2S Shorty
The Losi 1/12 IMSA GROM GT3 brings the Chevrolet Corvette Z06 GT3.R and Ford Mustang Dark Horse GT3 to a compact AWD on-road racing platform. Both models use the same stock 2S brushed power system, making battery selection straightforward once the physical dimensions, mounting method and connector requirements are understood.
Each car includes a 1400mAh 2S Smart LiPo battery. For drivers who want additional capacity for practice laps, parking-lot driving or casual track sessions, a compact 2200mAh 2S battery provides an alternative without increasing the nominal voltage.
Our featured option is the CNHL Black Series 2200mAh 7.4V 2S Shorty 40C LiPo Battery with XT60 Plug. Its compact design offers considerably more capacity than the original pack, although installation requires a different retention method and a suitable power connector solution.
Why Choose a 2200mAh 2S Battery for the Losi IMSA GROM?
Battery capacity is particularly relevant in small-scale on-road racing. A driving session often consists of repeated acceleration, braking and cornering rather than a single high-speed run. Having additional usable capacity can reduce the need to stop and recharge between casual sessions.
The CNHL 2200mAh Shorty provides three practical advantages:
- 57% more rated capacity: 2200mAh versus the included 1400mAh battery, providing additional stored energy for potentially longer driving sessions.
- Compact dimensions: At 76mm long, the battery is 25mm shorter than the stock Spektrum pack.
- 40C continuous discharge rating: Designed to supply current for demanding RC applications, while retaining the stock vehicle's 7.4V nominal 2S operating voltage.
Actual runtime depends on throttle use, driving surface, battery condition and vehicle setup. Greater capacity does not guarantee a proportional increase in driving time, and it does not increase the stock motor's maximum operating voltage.
Stock 1400mAh vs CNHL 2200mAh: Battery Comparison
| Specification | Stock Spektrum Battery | CNHL Shorty Upgrade |
|---|---|---|
| Capacity | 1400mAh | 2200mAh (+57%) |
| Voltage | 7.4V / 2S | 7.4V / 2S |
| Discharge Rating | 30C | 40C Continuous |
| Dimensions (L × W × H) | 101 × 31 × 21mm | 76 × 34 × 19mm |
| Approx. Weight | 85g | 103g |
| Battery Construction | Hardcase | Soft Pack |
| Power Connector | IC2 Smart | XT60 |
| Mounting | Smart Fit Clip-In | Strap / Hook-and-Loop |
Specifications are nominal manufacturer values. Actual battery dimensions and weights can vary. The CNHL pack is approximately 18g heavier than the stock Spektrum battery, despite its shorter length.
Will the CNHL 2200mAh Shorty Fit the Losi IMSA GROM GT3?
The Losi IMSA GROM GT3 has a published maximum battery footprint of 101 × 34mm. The CNHL 2200mAh Shorty measures 76 × 34 × 19mm, placing its nominal length and width within the published limits.
However, the CNHL battery is shorter than the original hardcase pack and is not designed to lock into the stock Smart Fit clip-in system in the same manner. Its 34mm nominal width also leaves no additional width allowance against the published limit. Check the actual pack dimensions and clearance before installation.
How to Secure a Shorty LiPo Battery
The IMSA GROM package includes a traditional Velcro battery strap and foam padding, providing an alternative to the quick-change battery system for different battery configurations.
- Remove the body and check the available battery mounting space.
- Position the CNHL Shorty pack with adequate clearance around the wires and chassis components.
- Use the supplied battery strap or a suitable hook-and-loop mounting arrangement, together with appropriate non-conductive padding where needed.
- Verify that the battery cannot slide, lift or interfere with moving components.
- Confirm that the body closes correctly and no power or balance wires are pinched before driving.
A secure installation matters more than a quick battery swap. Never operate the vehicle with a loose battery, and do not rely on adhesive alone unless the mounting system is designed and verified for that purpose.
XT60 to IC2: Connecting a CNHL Battery to the IMSA GROM
The stock Losi IMSA GROM GT3 uses an IC2 power connector, while the recommended CNHL 2200mAh battery comes with an XT60 plug. These connectors cannot be plugged directly into one another.
To use an XT60-equipped battery, a correctly oriented and appropriately current-rated XT60-to-IC2 adapter or a properly performed connector conversion is required. The vehicle uses a 25A-rated ESC, so an adapter must be selected for the expected electrical load, not merely for its connector shape.
CNHL also offers a 2-pack XT60-to-IC2 adapter cable for compatible low-current applications. This particular 22AWG adapter has not been validated for IMSA GROM drive-system loads and should not be assumed suitable for this vehicle without electrical verification.
A standard CNHL LiPo battery does not provide Spektrum Smart battery data communication. Connector conversion can provide an electrical power connection when correctly implemented, but it does not convert the battery into a Spektrum Smart battery.
Charging a CNHL 2S LiPo Battery
The Losi IMSA GROM GT3 includes a Spektrum S10 Smart G2 Mini USB-C charger for its supplied Smart battery. This charger is specified for compatible Spektrum Smart batteries and should not be used to charge the CNHL 2200mAh standard LiPo pack.
Use a suitable standard 2S LiPo balance charger that supports the battery's power connection and JST-XH balance lead. The standard full-charge voltage is 8.4V total (4.20V per cell). Follow the battery and charger instructions for charging current, storage and safe handling.
Battery Choices for Practice, Club Racing and Casual Driving
The IMSA GROM GT3 is designed around a manageable 2S AWD setup. On smaller on-road circuits, predictable handling and consistent driving can matter more than maximum straight-line speed.
For casual practice and unrestricted driving sessions, a higher-capacity 2S pack may be useful for reducing the frequency of battery changes. For organized spec racing, always check whether the class requires the original 1400mAh battery or sets limits on battery capacity, weight, connectors and mounting methods.
The stock brushed power system is specified for 2S operation. A 3S battery is not a standard upgrade for the original electronics. Changes to motor, ESC or gearing require separate compatibility checks and may make the car ineligible for stock racing classes.
Losi IMSA GROM GT3 Battery FAQ
What battery does the Losi IMSA GROM GT3 use?
Both the Corvette Z06 GT3.R and Mustang Dark Horse GT3 models include a Spektrum 1400mAh 7.4V 2S 30C Smart G2 hardcase LiPo battery with an IC2 connector.
Can I upgrade from 1400mAh to 2200mAh?
A 2200mAh standard 2S LiPo retains the original nominal voltage while increasing rated capacity by approximately 57%. The CNHL Shorty is a promising size-based upgrade option, provided the battery is securely mounted and connected using appropriately rated components. A completed vehicle-specific electrical and mounting test is still recommended.
Does the CNHL 2200mAh battery fit the Smart Fit battery tray?
Its nominal 76 × 34mm footprint is within Losi's published 101 × 34mm limit, but it does not provide the same clip-in retention as the stock battery. Use a secure strap-based arrangement and verify the actual battery clearance, height and cable routing.
Do I need an XT60-to-IC2 adapter?
Yes, if retaining the vehicle's IC2 power connector and the battery's XT60 plug. The adapter must have the correct connector orientation, polarity and adequate current capacity for the vehicle. Do not assume that every XT60-to-IC2 adapter is suitable for a 25A-rated ESC.
Can I charge a CNHL battery with the included Spektrum USB-C charger?
No. The included Spektrum S10 Smart G2 Mini is intended for compatible Spektrum Smart batteries. Charge the CNHL standard 2S pack with a compatible LiPo balance charger instead.
Will a 2200mAh battery make the IMSA GROM faster?
Not by itself. Both the original pack and CNHL upgrade use 7.4V nominal 2S voltage. The main benefit is additional capacity, not a guaranteed increase in top speed or acceleration.
Can I use a 3S LiPo in the stock IMSA GROM?
No. The original brushed motor and ESC setup is specified for 2S power. A 3S setup requires separately verified modifications and should not be treated as compatible with the stock vehicle.
Is the same battery suitable for both the Corvette and Mustang versions?
Both LOS-2165T1 Corvette and LOS-2165T3 Mustang use the Losi IMSA GROM GT3 2S platform and share the same published battery requirements. The same dimensions, mounting checks and electrical considerations apply to both.
Explore More CNHL RC Batteries and Accessories
Looking for batteries for another Losi platform or comparing different 2S sizes? Browse these CNHL collections for more options:
- LiPo Batteries for Losi RC Cars
- CNHL 2S LiPo Batteries
- CNHL RC Car Batteries
- RC Battery Connectors and Adapters
- ISDT RC Battery Chargers
Final fit reminder: The CNHL 2200mAh 2S Shorty is recommended for evaluation as a higher-capacity alternative based on its nominal dimensions and electrical specification. Confirm actual battery clearance, secure strap mounting, connector current rating and proper balance charging before operation. Competition use is subject to local race rules.
