Kelford Cams Extreme Valve Spring Kit - B58 / S58
Ships from the brand or distributor, usually in 3–7 business days
Make sure this fits your car
Fits: BMW M140i (F20), M240i (F22), 340i (F30), 440i (F32), 540i (G30), 740i (G11), X3/X4 M40i (G01/G02, 2018–2019), M340i (G20), M440i (G22), M240i (G42), Z4 M40i (G29), 540i (G30, 2020+), 740i (G11, 2020+), X3/X4 M40i (2020+); Toyota GR Supra 3.0 (A90/A91); BMW S58: M3 (G80/G81), M4 (G82/G83), M2 (G87), X3 M (F97), X4 M (F98). Confirm your exact car with us before ordering.
- Shipping at real carrier rates
- 30-day returns on unused parts
- Fitment help before you buy
This is Kelford's top-tier valve spring kit for the B58 and S58, meant for high-boost builds making well over 1000 hp. It's designed to go with Kelford's Stage 2 and Stage 3 camshafts, using a machined spring seat to push seat pressure as high as possible.
What you get
- Progressively wound beehive springs in PACALOY wire.
- Titanium retainers.
- Precision-machined spring seat to maximize seat pressure.
- 105 lb of seat pressure at a 35 mm installed height, and 210 lb at 10.8 mm of valve lift.
- Coil bind height of 23.6 mm.
Brand: Kelford Cams · Part #: KVS58-BTX
BMW M140i (F20), M240i (F22), 340i (F30), 440i (F32), 540i (G30), 740i (G11), X3/X4 M40i (G01/G02, 2018–2019), M340i (G20), M440i (G22), M240i (G42), Z4 M40i (G29), 540i (G30, 2020+), 740i (G11, 2020+), X3/X4 M40i (2020+); Toyota GR Supra 3.0 (A90/A91); BMW S58: M3 (G80/G81), M4 (G82/G83), M2 (G87), X3 M (F97), X4 M (F98). Confirm your exact car with us before ordering.
| Model | Chassis | Years | Engine | Fits |
|---|---|---|---|---|
| M140i | F20/F21 | 2016–2019 | Gen 1 B58 | |
| M240i | F22/F23 | 2016–2021 | Gen 1 B58 | |
| 340i | F30/F31/F34 | 2016–2019 | Gen 1 B58 | |
| 440i | F32/F33/F36 | 2017–2020 | Gen 1 B58 | |
| 540i | G30/G31 | 2017–2019 | Gen 1 B58 | |
| 740i | G11/G12 | 2016–2019 | Gen 1 B58 | |
| X3 M40i | G01 | 2018–2019 | Gen 1 B58 | |
| X4 M40i | G02 | 2019 | Gen 1 B58 | |
| 640i GT | G32 | 2018–2019 | Gen 1 B58 | |
| M340i | G20/G21 | 2019–2024 | Gen 2 B58 (TU) | |
| M440i | G22/G23/G26 | 2021–2024 | Gen 2 B58 (TU) | |
| M240i | G42 | 2022–2024 | Gen 2 B58 (TU) | |
| Z4 M40i | G29 | 2019+ | Gen 2 B58 (TU) | |
| GR Supra 3.0 | A90/A91 | 2020+ | Gen 2 B58 (TU) | |
| 540i | G30/G31 | 2020–2023 | Gen 2 B58 (TU) | |
| 740i | G11/G12 | 2020–2022 | Gen 2 B58 (TU) | |
| X3 M40i | G01 | 2020+ | Gen 2 B58 (TU) | |
| X4 M40i | G02 | 2020+ | Gen 2 B58 (TU) | |
| X5 xDrive40i | G05 | 2019–2023 | Gen 2 B58 (TU) | |
| X6 xDrive40i | G06 | 2020–2023 | Gen 2 B58 (TU) | |
| X7 xDrive40i | G07 | 2019–2022 | Gen 2 B58 (TU) | |
| 840i | G14/G15/G16 | 2019+ | Gen 2 B58 (TU) | |
| INEOS Grenadier | Station Wagon/Quartermaster | 2023+ | Gen 2 B58 (TU) | |
| M340i | G20/G21 | 2025+ | Gen 3 B58 (48V) | |
| M440i | G22/G23/G26 | 2025+ | Gen 3 B58 (48V) | |
| M240i | G42 | 2025+ | Gen 3 B58 (48V) | |
| M3 | G80/G81 | 2021+ | S58 (BMW M) | |
| M4 | G82/G83 | 2021+ | S58 (BMW M) | |
| M2 | G87 | 2023+ | S58 (BMW M) | |
| X3 M | F97 | 2020–2024 | S58 (BMW M) | |
| X4 M | F98 | 2020–2025 | S58 (BMW M) |
Not sure? Email sales@b58racing.com with your VIN.
- Ships from the brand or distributor, usually in 3–7 business days.
- Shipping is charged at the carrier's rate, shown at checkout. Orders over 70 lb ship by freight for a flat $99.
- Unused parts can be returned within 30 days. Some items are marked no-refund in their description.
Full details are on our shipping and returns page.
Guides for this part
B58 Common Problems by Generation (Gen 1, Gen 2 and 2025+) and the Parts That Fix Them
The B58 is one of BMW's most reliable modern engines, and most of its problems are leaks, not failures. The ones that come up again and again are the oil filter housing gasket, coolant leaks (water pump, expansion tank,
S58 Common Problems (G80 M3, G82 M4, G87 M2, X3 M and X4 M) and the Parts That Fix Them
The S58 is still a young engine, and its public problem record is short. The most serious items we found are two BMW delivery stops on small groups of early engines: a 2019 X3 M and X4 M build window where BMW replaced t
BMW S58 Mods Guide: M2, M3, M4, X3 M and X4 M Upgrades in Order
On an S58, start with a tune and cooling. These cars make a lot of power stock, and heat is what holds them back on hot days and back-to-back pulls. Next come downpipes and a tune built for them, then fuel: an ethanol an
Pairs well with
MMX Billet Oil Filter Housing for BMW B58
MMX Performance Replacement Oil Filter for BMW B58 & B57 Engines
Eventuri Toyota A90 Supra B58 Black Carbon Engine Cover
