ECU, Upgrades & Extras

This page has three main sections: 1) ECU Options, 2) Kit Upgrades and 3) Optional Extras.

1) ECU Options

As outlined in the Introduction, the kit contains all the mechanical parts required for the Honda engine conversion.  To get your engine running, there is a decision to be made about the ECU.  Firstly, to overcome the ECU immobiliser and, secondly, to allow the tuning (remap) of the engine for maximum power.

The three main ECU options are:
i) use the factory ECU with an immobiliser bypass unit
ii) convert the factory ECU into a mappable ECU with the Hondata K-Pro upgrade
iii) use another aftermarket ECU of your choice.

The electrical instructions provided with the build manual contain all the information required for ECU options i) and ii).  If you choose a different ECU per iii), then our instructions will help to some degree but it’s a much bigger DIY task.

Pricing for ECU options i) and ii) are as follows:

Option Description £GBP
i) Hondata K-Pro ECU upgrade (latest v4 now available).   Highly recommended to help extract the maximum performance from your engine and our sports exhaust system, the latest Hondata K-Pro ECU package converts the factory ECU into a fully programmable ECU.  The upgrade includes fitting the K-Pro board, installing a USB port so you can hook up your PC/laptop to the ECU and the programming lead. You also get access to various base maps to get your car started, K-Manager software to adjust a multitude of settings (including enabling/disabling the ECU’s built-in immobiliser), onboard data-logging and bluetooth connectivity to name just a few features.  The standard ECU from your donor package will be required on an exchange basis or we can supply a donor ECU.  We recommend your car is mapped on a rolling road (dyno) once the conversion is complete.   The Doctronic option works in the similar way, you lose the Bluetooth connectivity but it is cheaper.

Note: we only supply ECUs with conversion kits, not separately.  If you want to buy separately, please contact your local country’s supplier.

Hondata K-Pro v4 £664 + £18 shipping to/from Hondata.

Doctronic ProEcuK £550.

Donor ECU  (if required) £120.

ii) Honda ECU immobiliser bypass box.  The original Honda ECU usually has a built-in immobiliser, so if you don’t want to go to the expense of a K-Pro or other aftermarket ECU, then you will need one of these “black boxes” to start your engine.  Not recommended for long-term use as your engine will run lean with our kit’s sports exhaust manifold.  £148
iii) Other ECU £You choose

2) Kit Upgrades

As the kit is extremely comprehensive, we offer just a few upgrades alongside a range of optional extras (below).

Option Description £GBP
Sports Cat upgrade Upgrade from the standard decat link pipe to include a sport-spec catalytic converter. Helps to maintain high power while meeting emission test requirements.  £320
Upgraded driveshaft grease For occasional track use and/or high-power conversion, upgraded driveshaft grease (one for the inners, one for the outers) is recommended. For extensive track use, motorsport-spec NEO and OSK greases are recommended, Grease will be dispensed into separate sachets, sufficient for one pair of shafts.  Note, shafts are supplied in kit form for DIY assembly when upgraded grease is requested. Option 1: Upgraded tripode & CV grease £40. Option 2: Motorsport NEO HPCC1 & OKS422 £110.
Custom powdercoat colour Upgrade to a colour of your choice for the fabricated parts (black as standard, no cost option). Colour of your choice £30
Custom hose colour Upgrade to coloured silicone hoses (black as standard, no cost option). Red, blue, yellow, purple, green, orange, white £25

3) Optional Extras

We offer a range of optional extras; some of these are highly recommended, others are simply highly desirable!   They can be supplied alongside our conversion kit or on a standalone basis.

Option Description £GBP
Engine preparation kit Get your donor engine into good shape before it’s fitted to your Lotus with the following parts:  Genuine Honda timing chain tensioner, timing chain, HAMP oil filter, set of 4 x NGK Iridium long-life spark plugs and a thermal exhaust manifold gasket.  From Jul 20, this package also includes a new water pump.  £328. See below for clutch and flywheel options.
Uprated fuel pump This pump is a direct plug & play replacement utilising modern pump technology and supports power outputs up to 400bhp. Bear in mind the standard pump will be running at its maximum to fuel the Honda engine (and will be up to 20 years old). S1 (as pictured) £234, S2 £247.
Refurb’d valve cover A refurbished valve cover will help to show off your newly installed Honda VTEC engine.  Various colours and finishes available including bright red crinkle as shown. From £140 exchange (your old cover required or surcharge £80).
ITG Intake ITG ARAB airbox and ITG Maxogen filter, to fit the Stark intake pipe.  £162
PLX wideband kit The PLX unit is our recommended wideband kit for Hondata K-Pro users.  Comes complete with the AFR unit, a 52mm high-contrast OLED display gauge and the latest Bosch LSU 4.9 O2 sensor.  £196
K-Tuned parts The full range of K-Tuned parts for tuning and dressing up your K20 installation.  Too many to list here, please ask for a competitive price.  £ask
Uprated rear toe link kit Strength for strength the lightest, stiffest, and easily the most durable kit available with unsurpassed bearing reliability. The rest of the kit is designed to last the life of the car. Comes fully assembled and pre-set with the correct bump steer shims where this information has been supplied by the customer, otherwise the Lotus recommended settings will be used. Detailed fitting instructions are supplied. S1 with steel uprights £335, S1 Ali £499, all S2 £335.
MFactory LSD MFactory limited slip differentials (LSD): helical and plate versions available.  Available with or without new diff carrier bearings and the correct gearbox oil. Helical: £606,  Racepack £692.
Plate: £778. Carrier bearings £48/pair.  2L Torco MTF £26 or RTF £48
Quaife LSD Quaife limited slip differential (LSD). This is another helical/torsion (not plate) diff which has been optimised for RWD so ideally suited to Honda-Elise conversions. £715. Carrier bearings £48/pair.  2L Torco MTF £26 or RTF £48
Clutch kits Clutch kits.  We can supply Genuine Honda, Exedy and Competition Clutch Stage 1, 2 & 3 clutch kits at competitive prices. Genuine Honda £226, Stg1 £239, Stg1 Ceramic £246, Stg 2 £315, Stg 3 £330.  Others £ask.
Lightweight flywheel Ultra-lightweight flywheel, approx 4kg.  We recommend using new Genuine Honda studs (x8 required) when fitting. Flywheel £236, studs £37
Wishbone bushes Powerflex suspension bushes, full set of 16 bushes to cover all wishbones. Purple £270 (road series), Black £280 (track series)
Nitron dampers Nitron sports suspension for road, track or race use. £ASK for the NTR40  – road version (spring rates 400fr / 475re) or track version (450fr/525re).
Alloy Rad


Upgraded alloy radiator (recommended for trackday and race cars).  Also does away with the plastic end caps of the OEM radiator which are prone to leakage.  Available with or without a pair of new silicone hoses, one with air bleed screw, and matching clips. £228 for rad, £90 for hoses, £318 in total
Mount Rubbers New Rover rubber engine mounts (engine & gearbox side). £96 for the pair
TTS Supercharger Kit TTS Performance has developed this superb supercharger conversion to give you a 100%+ power gain and better drivability then the standard car. It enables the engine to pull hard through its entire power band with no glitches or fuss, no throttle lag, just seamless power.  This conversion requires very little maintenance, utilising the genuine Honda belt tensioning system means OEM reliability. The chargecooler/pre-rad system enhances the performance by keeping the intake charge temperature at a less than 55 deg C. C30-94 ​Kit Price (300-400BHP) £4145. C38-81 Kit Price (400-550BHP) £4300.
CPL Supercharger Kit CPL Supercharger Kit for Honda-converted Elise/Exige.  This all-new kit has been designed to considerably outperform the JR kit and provide further upgrade paths for those who desire the ultimate in supercharged performance.  Includes:
– Supercharger unit
– Gear drive assembly
– Inlet manifold
– Throttle body adaptor
– Bypass valve
– 7 rib pulley and belt
– Map sensor relocator
– Fixings and O ring seals
– One year/20,000 km warrantyThe new CPL Racing supercharger kit will product 350 hp straight out of the box, this is 50bhp more than the previous Jackson.
£TBC (currently back in R&D)
RBC Intake Manifold Genuine Honda RBC intake manifold kit, CNC-machined so it’s a direct fit to the K20 head and proven to give good gains (+10-15bhp with a remap), complete with the required throttle-body adaptor plate for fitment of the K20 throttle body.  Fitting note: you may need to rework the bulkhead in order to fit this manifold as it’s longer than the standard version, see our FAQ for more info. Manifold £480, throttle adaptor plate (standard or 70mm version) £50
Skunk2 70mm Throttle Body Designed to be used with Skunk2 Pro Series Intake Manifolds as well as OEM and other aftermarket intake manifolds for bolt-on horsepower and torque gains by maximizing engine airflow.  Skunk2 throttle bodies undergo an extensive design and testing process to produce a throttle body that doesn’t just provide more flow but retains smooth drivability and OEM throttle characteristics. £280
Skunk2 cams Skunk2 Tuner drop-in camshafts.  Offer  +12-15 hp gains with no other valvetrain mods required.  Designed to optimise mid-range and top-end horsepower and torque, with peak power moved up the RPM band. As a result, VTEC crossover is seamless, allowing for the broadest powerband possible. £820 / pair
Skunk2 valve train Available now.  Details follow.  £ask
Honda FD Genuine Honda 5.1 final drive kit.  Effectively, it shortens all the gearbox ratios meaning more acceleration through the gears and less of a gap between the gears (whilst reducing top speed).   £498
Rebuild K20A/K20A2 engine rebuild parts – piston rings, conrod bearings, main bearings, timing chains, tensioners etc etc.   Get your conversion off to the best possible start with an engine refresh.  Huge range of parts in stock for fast delivery. Please ask for a quote

How to Order

See How to Order to obtain a personalised quotation.

Prices are in £GBP and exclude delivery.

Pricing effective 1st February 2024.

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