BassVirolla wrote: ↑17 Jan 2026, 00:00
TeamKoolGreen wrote: ↑16 Jan 2026, 22:58
vorticism wrote: ↑16 Jan 2026, 20:35
"

35kg HEAVIER

" is a meme at this point, has to be the most misunderstood part of these regulation and wuzak is single-handedly responsible for dispelling this myth online, lol.
So far nobody claiming that the 2026 PU is not 34 kg heavier hasn't produced a single source to prove it.
My source is The Race
The power units are getting a lot heavier again. The MGU-K is increasing from 7kg to 20kg total, and the battery from around 20-25kg to a minimum weight of 35kg. Even with no MGU-H, which is a saving of 4kg, some other ancillary part changes will up the total weight of the engine from 151kg to 185kg in 2026.
https://www.the-race.com/formula-1/what ... rovements.
Referring to the rulebook (5.7.1 - 5.7.3 - 5.20.7 and Appendix 3 in which the operational groups are defined), ICE + TC + MGUK equates to 150kg.
The 35kg are defined in 5.19.9 as the ES Main Enclosure. Appendix 3 defines ES Main Enclosure as:
- Enclosure
- Energy storage
- Control electronics
- All electric ancilliaries related to ES
So, minimum "engine" (ICE + TC + MGUK) mass is 150 kg.
C5.5 Mass and centre of gravity
C5.5.1 Depending on where the MGU-K Mechanical Transmission (as defined in item 27 of Appendix C4) is located, the overall mass of the ICE “PU Mass group” elements as referred to in Appendix C3 must be no less than the values defined below:
a. If all of the speed ratio of the MGU-K Mechanical Transmission is located in the RV-PU-ERS the total mass of the ICE must be no less than 130.0kg.
b. If all of the speed ratio of the MGU-K Mechanical Transmission is located in the RV-PU-ICE the total mass of the ICE must be no less than 134.0kg.
c. If part of the speed ratio of the MGU-K Mechanical Transmission is located in both the RV-PU-ICE and the RV-PU-ERS the total mass of the ICE must be no less than 132.0kg.
C5.18 MGU-K
C5.18.7 Depending on where the MGU-K Mechanical Transmission is located, the total mass of the MGU-K “PU Mass group” elements as referred to in Appendix C4 must be no less than the values defined below:
a. If all of the speed ratio of the MGU-K Mechanical Transmission is located in the RV-PU-ERS the total mass of the MGU-K must be no less than 20.0kg.
b. If all of the speed ratio of the MGU-K Mechanical Transmission is located in the RV-PU-ICE the total mass of the MGU-K must be no less than 16.0kg.
c. If part of the speed ratio of the MGU-K Mechanical Transmission is located in both the RV-PU-ICE and the RV-PU-ERS the total mass of the MGU-K must be no less than 18.0kg.
The total mass of item 29 (MGU-K torque sensor) and item 31 (K torque sensor shaft and mechanical connection between MGU-K and ICE) must be allocated to either the MGU-K or the ICE to assess compliance with this article and article C5.5.1.
C5.17 Energy Recovery System (ERS)
C5.17.9 The minimum mass for the ES Main Enclosure PU Mass group elements as defined in Appendix C4 is 35.0kg. The procedure which will be used to determine this value may be found in the document FIA-F1-DOC-Cxxx.
The following items are included in the ES Main Enclosure mass group exclusively (from Table 1, Appendix C4):
- ES Main Enclosure (ESME)
- Energy Store
- Regulatory DC sensors and Insulation monitoring device
- Safety devices (Fuses, Contactors, MSD, relays)
- Busbars, connectors conductors, looms or any other component fitted inside the ESME that is not explicitly mentioned in any other rows of this table.
- CU-K
- DC-DC Unit
- General electrical devices inside the ESME, including Power distribution board, Driver for PU electric pumps, LV fuse box and any electronic box exclusively used for PU functionalities.
- Non ICE-mounted ERS cooling system including pumps, associated motors, actuators, excluding tubes and hoses
Items that can be counted in the ES mass or another "mass group":
- MGU-K torque sensor signal conditioning module (SCM) (MGU-K or ICE or ESME)
- General electrical devices outside or on the ESME, including Power distribution board, Driver for PU electric pumps, LV fuse box and any electronic box exclusively used for PU functionalities. (ES or ICE)
- Source of energy independent of the ES exclusively used for PU functionalities (ES or ICE)
From the 2024 PU regulations (PU was frozen from 2022 to 2025):
5.5 Mass and centre of gravity
5.5.1 The overall mass of the power unit must be a minimum of
151kg.
5.5.2 The centre of gravity of the power unit must be above Z=200.
5.5.3 The total mass of
the part of the ES that stores energy, i.e. the cells (including any clamping plates) and electrical connections between cells, must be no less than 20kg and must not exceed 25kg. [Energy Store in 2026]
5.13 Energy Recovery System (ERS)
5.13.6 The following elements of the power unit must be installed wholly within the survival cell:
a. ES elements as defined in lines 16 and 17 of Appendix 3 to these regulations.
b. Any
DC-DC converter connected to ES HV DC bus. Includes active parts, enclosure, brackets and supports.
c.
CU-K. Includes active parts, enclosure, brackets and supports.
d. CU-H. Includes active parts, enclosure, brackets and supports.
e. HV DC connections between ES and CU-K/CU-H/DC-DC converter. Includes all conductors, insulation, EMC screening, mechanical and thermal shielding.
The minimum values of volume and mass for these groups of components are 22.0 l and 31.0 kg respectively. The procedure which will be used to determine these values may be found in the Appendix to the Technical and Sporting Regulations.
These are some of the items are exluded from the PU mass (from Table 1, Appendix 3):
- ES parts defined in Article 5.5.3
- ES excluding parts defined in Article 5.5.3
The following is included in the PU mass for 2024:
- PU-CE excluding associated brackets, supports, screws, nuts, dowels, washers or cables.
This includes the CU-K, which is in the ESME mass group for 2026.
To summarise:
2025 PU minimum mass = 151kg, excluding the ES.
2026 ICE + Turbo + MGUK + MGUK Transmission = 150kg.
2026 ESME minimum mass is 35kg.
The equivalent for 2025 is 31kg, though the Power Unit Control Electronics (including the CU-K) is also included in the PU.