GM LS3 6.2 V8 Petrol Swap
Donor: GM LS3 6.2 V8 (C6 Corvette / Camaro SS / CTS-V)
The V8 monster swap. 430bhp / 570Nm of naturally-aspirated small-block from the C6 Corvette, dropped into the Defender bay with GM Performance controllers. Cheap horsepower, endless tuning, and a soundtrack no diesel can match. The petrol counterpart to the M57.
ECU Solution
GM E38 factory ECU flashed by BlackBear/HP Tuners, or Holley Terminator X standalone
Gearbox Options
4L60E / 4L65E auto with Advance Adapters LT230 adapter, or Tremec T56 6-speed manual with custom bellhousing
Compatible Models
Defender 90 · Defender 110 · Defender 130
Requires custom fuel system (return-line, high-pressure pump, 60L+ tank), stainless headers routed around the steering box, upgraded cooling (twin electric fans + high-flow rad), and reinforced axles/prop shafts to handle the torque. Not road-legal in every jurisdiction — check emissions/type-approval before starting.
Step-by-step guide
10 steps- 0101StepInfo 2 days
Strip original driveline
Remove the OEM engine, gearbox, transfer box (kept for LT230 reuse), radiator, exhaust, fuel tank and full engine loom. Cap the fuel lines — petrol conversion means the entire fuel system will be replaced.
ToolsEngine crane, Socket set, Fuel drain pan
PartsEngine stand, Storage
- 0202StepCaution 1 day
Fabricate LS engine mounts
Weld in LS-specific side mounts (Nene Overland or custom). LS3 is wider than a Tdi — check steering-box clearance on the driver-side head. Trim the inner wing if needed.
ToolsMIG welder, Plasma cutter, Level
PartsLS mount kit, 8mm plate steel
- 0303StepCaution 1 day
Mate 4L60E to LT230
Bolt the 4L60E auto to the Land Rover LT230 using an Advance Adapters LS-to-LT230 adapter and correct input gear. Use a shortened GM torque converter.
ToolsTorque wrench, Alignment dowels
PartsAdvance Adapters 4L60E-LT230 kit, GM torque converter
- 0404StepCritical 2 days
Fit stainless long-tube headers
CRITICAL clearance job — route custom stainless long-tube headers around the steering box and down past the chassis rails. Ceramic-coat to protect wiring and starter.
ToolsMIG/TIG welder, Angle grinder, Ceramic-coat spray
PartsCustom stainless headers, V-band clamps, Ceramic coating
- 0505StepCritical 2 days
Install E38 ECU and Painless GM loom
Fit the LS3 E38 controller with a Painless or Current Performance GM loom. Delete VATS/anti-theft in the flash. Mount the ECU in the cabin, sealed from heat.
ToolsMultimeter, HP Tuners cable, Crimper
PartsE38 ECU (VATS-deleted), Painless LS3 loom, Relay/fuse block
- 0606StepCritical 1 day
High-pressure return-flow fuel system
LS3 wants 58 psi with a bypass return. Fit a Walbro 460 in-tank pump in a new 60-litre baffled tank, 10-micron filter, -6 AN feed and -6 return.
ToolsAN wrenches, Cutter, Flare tool
PartsWalbro 460 pump, Baffled 60L tank, AN-6 hose kit, Bypass regulator
- 0707StepCaution 5 hours
Uprated cooling — twin fans + high-flow rad
Install a Ron Davis or Griffin aluminium radiator (min 25mm core) with twin SPAL 12" pullers. Add a dedicated transmission cooler for the 4L60E.
ToolsScrewdrivers, Coolant funnel
PartsRon Davis radiator, 2x SPAL 12" fans, Trans cooler, Silicone hoses
- 0808StepCritical 1 day
Reinforce driveline for 570Nm
Ashcroft ATB or full-locker rear diff, Ashcroft heavy-duty axle shafts, and new front + rear prop shafts (GKN). Original 10-spline shafts WILL snap.
ToolsTorque wrench, Bearing puller
PartsAshcroft ATB, HD axle shafts, Custom props
- 0909StepCaution 1 day
Custom exhaust from headers to tail
Twin 2.5" stainless system merging into a single 3" over the rear axle, with a straight-through resonator. Heat-shield the fuel tank and prop tunnel.
ToolsPipe bender, MIG welder, Cutter
PartsStainless 2.5" tubing, Resonator + muffler, Heat shield
- 1010StepCritical 1 day
Tune, break-in, dyno remap
Fill with 5W-30, prime oil, then crank without spark plugs to build pressure. Start, verify idle, then complete a 500-mile break-in before booking a dyno session with an LS-specialist for a full VE/spark map.
ToolsHP Tuners, OBD dongle, Wideband O2
Parts5W-30 synthetic, Coolant, Premium fuel
OEM vs Aftermarket / Parts matrix
10 systems · GBP refSide-by-side sourcing options for the GM LS3 6.2 V8 swap. Prices are indicative UK trade, exclusive of VAT and shipping. Verify fitment against your chassis year and steering hand.
| System / Part | OEM / Genuine | Aftermarket | Compatibility |
|---|---|---|---|
Engine Long block (LS3 6.2) | GM LS3 crate 19434648 PN 19434648 £8,500 – £11,000 430bhp / 570Nm. Sealed 3-yr GM warranty. | Reman C6 Corvette LS3 pull-out £4,500 – £6,500 Mileage varies. Insist on compression + leak-down report. | Fits 90/110/130 with fabricated mounts. Bell-housing pattern = LS. |
Engine Engine management (ECU) | GM E38 ECU + T-case harness PN 12633049 £650 – £900 OE calibration; requires HP Tuners re-flash for standalone. | Holley Terminator X Max 550-919 PN 550-919 £1,450 – £1,650 Plug-and-play standalone, integrated trans control (4L60E/4L65E). | Both work on 24x LS3. Holley preferred if deleting VATS/OnStar. |
Driveline Gearbox | GM 4L65E automatic £1,800 – £2,400 OE C6 pairing; needs Defender transfer adapter. | Tremec T56 Magnum 6-spd manual £3,200 – £4,000 Rated 700Nm. Requires custom pedal box + hydraulic clutch. | Both need Ashcroft LT230 adapter plate (see Adapter row). |
Driveline LT230 adapter plate | — (no OEM part) n/a GM never shipped an LT230 mating kit. | Ashcroft LS-to-LT230 adapter PN LSA-LT230 £950 – £1,200 CNC billet, includes spigot + input shaft. 4-week lead time. | Mandatory. Also fits Range Rover Classic LT230. |
Cooling Radiator + fan pack | GM C6 Corvette radiator £380 – £520 Down-flow; too wide for Defender nose panel without mods. | Allisport alloy Defender/LS crossflow £850 – £1,100 Direct fit to Defender front panel, 55mm core, twin SPAL fans. | Aftermarket strongly recommended. OEM needs custom shroud + panel cut. |
Fuel Fuel system (return-flow, 58 psi) | GM Corvette in-tank module £420 – £580 Doesn't fit Defender tank; donor-only. | Walbro 450lph + Aeromotive FPR kit £380 – £520 Fits Defender OE tank with sender adapter. 58 psi regulated return. | Aftermarket required — Defender tank is not GM-compatible. |
Exhaust Headers / manifolds | GM cast LS3 manifolds £220 – £320 Fits without steering box clash on RHD. | Kooks / Pace long-tube 1-3/4" headers £1,100 – £1,600 +15-20bhp; will clash with RHD steering box — requires re-clocking. | Shorty/cast fine on LHD & RHD. Long-tube = LHD or box relocation. |
Chassis Engine + gearbox mounts | — (no OEM Defender/LS mount) n/a No GM or Land Rover mount exists. | V8 Developments LS-Defender mount kit £450 – £650 Bolt-in to Defender chassis rails, polyurethane bushes. | Mandatory. Verify chassis year — Puma (2007+) needs revised bracket. |
Driveshafts Front + rear props | Stock Defender props included Will fail under 570Nm torque within months. | GKN heavy-duty wide-angle props £680 – £900 pair 1350-series U-joints, rated for V8 torque. | Aftermarket required for reliable service life above 400Nm. |
Electrical Wiring harness | GM C6 factory harness (donor) £150 – £300 Requires full de-pinning and VATS bypass. | Current Performance standalone LS3/E38 harness £850 – £1,050 Pre-labelled, Defender-length, plug-and-play to Holley or E38. | Aftermarket cuts fitment time from ~30h to ~6h. |
EngineLong block (LS3 6.2)TAP
430bhp / 570Nm. Sealed 3-yr GM warranty.
Mileage varies. Insist on compression + leak-down report.
Fits 90/110/130 with fabricated mounts. Bell-housing pattern = LS.
EngineEngine management (ECU)TAP
OE calibration; requires HP Tuners re-flash for standalone.
Plug-and-play standalone, integrated trans control (4L60E/4L65E).
Both work on 24x LS3. Holley preferred if deleting VATS/OnStar.
DrivelineGearboxTAP
OE C6 pairing; needs Defender transfer adapter.
Rated 700Nm. Requires custom pedal box + hydraulic clutch.
Both need Ashcroft LT230 adapter plate (see Adapter row).
DrivelineLT230 adapter plateTAP
GM never shipped an LT230 mating kit.
CNC billet, includes spigot + input shaft. 4-week lead time.
Mandatory. Also fits Range Rover Classic LT230.
CoolingRadiator + fan packTAP
Down-flow; too wide for Defender nose panel without mods.
Direct fit to Defender front panel, 55mm core, twin SPAL fans.
Aftermarket strongly recommended. OEM needs custom shroud + panel cut.
FuelFuel system (return-flow, 58 psi)TAP
Doesn't fit Defender tank; donor-only.
Fits Defender OE tank with sender adapter. 58 psi regulated return.
Aftermarket required — Defender tank is not GM-compatible.
ExhaustHeaders / manifoldsTAP
Fits without steering box clash on RHD.
+15-20bhp; will clash with RHD steering box — requires re-clocking.
Shorty/cast fine on LHD & RHD. Long-tube = LHD or box relocation.
ChassisEngine + gearbox mountsTAP
No GM or Land Rover mount exists.
Bolt-in to Defender chassis rails, polyurethane bushes.
Mandatory. Verify chassis year — Puma (2007+) needs revised bracket.
DriveshaftsFront + rear propsTAP
Will fail under 570Nm torque within months.
1350-series U-joints, rated for V8 torque.
Aftermarket required for reliable service life above 400Nm.
ElectricalWiring harnessTAP
Requires full de-pinning and VATS bypass.
Pre-labelled, Defender-length, plug-and-play to Holley or E38.
Aftermarket cuts fitment time from ~30h to ~6h.
LS3 Swap · Suppliers & Lead-Time Board
Where to source the hard parts a Defender LS3 build actually turns on: crate engine, adapter plate, standalone ECU, and cooling.
| Vendor | Scope | Indicative price | Lead time | Stock | Shipping | |
|---|---|---|---|---|---|---|
GM Performance (Chevrolet Performance) USA · Direct + dealer network | LS3 6.2 crate long block (P/N 19434648) — 430 bhp, 3-yr warranty Cheapest new-engine route. Order via authorised UK dealer (V8 Developments, Real Steel) to bundle VAT. | £8,500 – £11,000 | 2–4 weeks | In stock | Freight from US warehouse; UK/EU duty applies | Visit → |
Real Steel UK · Bicester | LS3 crate + install parts (loom, ECU flash, adapter, cooling) Established GM LS distributor. Will assemble complete swap packages. | £9,800 – £14,500 | 3–6 weeks | In stock | UK next-day; EU/MENA on request | Visit → |
V8 Developments UK · Lincolnshire | LS3 packages incl. E38 ECU calibration + Holley option Strong on ECU flashing and standalone conversions. | £10,500 – £15,000 | 4–8 weeks | Made to order | UK & Ireland pallet; export by quote | Visit → |
Ashcroft Transmissions UK · Dunstable | LS-to-LT230 adapter plate + machined input shaft (LSA-LT230) The de-facto adapter for LS + LT230. Batch machined — plan ahead. | £950 – £1,200 | 3–5 weeks | Made to order | Worldwide courier | Visit → |
Holley Performance USA · Bowling Green KY (UK dealer: Holley Europe) | Terminator X Max 550-919 standalone ECU + 4L60E/4L65E trans control Removes GM VATS/OnStar dependency. Handset tuning included. | £1,450 – £1,650 | 1–3 weeks | In stock | UK & EU stock via Demon Tweeks / Merlin Motorsport | Visit → |
Turner Motorsport USA · Amesbury MA | LS accessories: pulleys, radiator hoses, oil coolers | £150 – £900 per line | 1–2 weeks | In stock | USPS/DHL worldwide | Visit → |
Nanocom / Blackbox Solutions UK · Diagnostics | Post-swap Defender BCM diagnostics + immobiliser bypass advice Not GM-side, but you'll need it to keep the Defender dash talking. | £350 – £550 | In stock | In stock | UK/EU tracked | Visit → |
LS3 6.2 crate long block (P/N 19434648) — 430 bhp, 3-yr warranty
Cheapest new-engine route. Order via authorised UK dealer (V8 Developments, Real Steel) to bundle VAT.
LS3 crate + install parts (loom, ECU flash, adapter, cooling)
Established GM LS distributor. Will assemble complete swap packages.
LS3 packages incl. E38 ECU calibration + Holley option
Strong on ECU flashing and standalone conversions.
LS-to-LT230 adapter plate + machined input shaft (LSA-LT230)
The de-facto adapter for LS + LT230. Batch machined — plan ahead.
Terminator X Max 550-919 standalone ECU + 4L60E/4L65E trans control
Removes GM VATS/OnStar dependency. Handset tuning included.
LS accessories: pulleys, radiator hoses, oil coolers
Post-swap Defender BCM diagnostics + immobiliser bypass advice
Not GM-side, but you'll need it to keep the Defender dash talking.
Independent shortlist. Defender101 is not affiliated with any listed vendor. Confirm pricing, stock, and shipping to your region on the vendor's own site before ordering — VAT, duties, and lead times shift frequently.