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Mini Classic Mini Mk1-Mk7
Power hp
Torque Nm
Displacement L
Layout
Swap overview with verified parts, part numbers and sources.
K20A in Classic Mini.
Documented from 32 recorded sources: 4 of the ten mandatory blocks are carried by two independent publishers, 4 remain open, 1 does not apply. Internal confidence 64%.
2.0 l inline-four, "double overhead cams, four valves per cylinder, variable valve timing". Published output figures differ by variant and by state of tune and must not be read as one number: 200 hp at 7,400 rpm for the UK-spec Civic Type R K20A2, 217 hp for the 2001-2006 Integra Type-R in the Mini Tec parts list, approximately 180 hp for the K20A3 in Mini Tec's own package, 215 hp for the Civic Type R engine in the Z Cars rear-engined car, 240 hp for the modified EP3 engine in a Clubman, and 250 bhp with 225 Nm for one Z Cars competition car.
Status: SUPPORTED · Confidence 72%
Naturally aspirated in every documented installation. The Z Cars mid-engined car is quoted at "200 hp in standard tune", the Mini Tec package engine at approximately 180 hp, and one heavily built Clubman is described as "naturally aspirated" at 240 h
The Mini Tec manual points at the 2001-2006 Integra Type-R (1998 cc, 217 hp) and the 2002-2006 Accord Euro-R. Mini Tec's own complete package is built on a used K20A3 with, in the vendor's words, a "good, used, low-mileage (usually less than 65K miles) engine". Documented cars use a "2.0 L K20A inline-four from a JDM Integra Type R", a "UK-spec 2002 Honda Civic Type R" K20A2, a "2.0 L K20 inline-four from a Civic Type R" and an "Ep3 K20". The donor has to supply more than the engine: Mini Tec lists "Honda engine, ECU, and dash wiring harness" as parts the customer provides, and the inner CV joints come from the Honda side while the outer ones stay Mini.
Engine and transaxle as one unit from a 2001-2006 Integra Type-R, a 2002-2006 Accord Euro-R or a Civic Type R, plus - in Mini Tec's own wording - the "Honda engine, ECU, and dash wiring harness". Hondata adds the specific harness needed: the K20A engine wiring harness, which plugs straight into the ECU A and B connectors. The kit makers supply the rest: Mini Tec the subframe, mounts, arms, extended steering arms and hybrid axle shafts with Honda inner and Mini outer CV joints, Potential Motorsport the subframe, mounts, arms, uprights, coilovers, brakes, driveshafts, radiator, manifold, pedal box and shifter - explicitly "minus engine, gearbox and no electronics/wiring". Additionally required from the Mini side or the aftermarket: an electronic speedometer, a fuel pump of 32-48 psi with a return line and an inline regulator, coil-over shocks and a front disc brake conversion. For the all-wheel-drive route Mini Tec requires a complete 1996-2001 CR-V AWD manual five-speed drivetrain including shifter cables, propshafts and rear differential, plus 1990-1997 Mazda Miata rear hubs, outer CV joints and disc brake parts.
Status: VERIFIED · Confidence 80%
Two independent kit makers on two continents, with different and openly stated trade-offs. Mini Tec supplies an MTK subframe with "Engine Mounting Bracket", "Engine Mounting Spacer (2)", "Transmission Adaptor Bracket", "Rear Transmission Stabilizer" and "Front Stabilizer Bar", and states plainly that "All of the K series kits will need an extended front end" - its package page quantifies that as approximately 90 mm. Potential Motorsport takes the opposite route: a "Wider track aircraft grade T45 Tubular Subframe" with a "4x K-series Billet engine mount kit 70A rating (fast road)" that "fits inside a stock length front end" for a round nose shell, at the price of "extensive modification" to the bulkhead. These are not contradictory statements but the two ends of one trade-off, and a forum member states it in a single sentence: "unless you are going to cut and modify the firewall it would require an extended front end". A second member in the same thread gives the same figure from the other side - "without moving the fire wall you will require a 90mm extended front" - and a third describes the alternative as moving the firewall four inches back, which a fourth calls "quite drastic".
No reliable combination-specific information found on oil pan, oil pickup and steering-rack clearance in this combination.
The Honda transaxle stays with the engine and is not part of either kit - both makers sell without a gearbox, Potential Motorsport in the words "complete kit minus engine, gearbox and no electronics/wiring", Mini Tec by listing "Honda K series engine/transmission" among the parts the customer supplies. What the kit provides instead is the mounting: Mini Tec supplies a "Transmission Adaptor Bracket", "Transmission Mounting Brackets" and a "Rear Transmission Stabilizer". On the entirely separate Z Cars rear-engine route the same engine is used with a "six-speed manual transaxle" driving the rear wheels; one competition car is described as having a "6 speed LSD gearbox kit", and a front-engined Clubman as having a "six-speed transmission".
Mini Tec mounts the transaxle with a "Transmission Adaptor Bracket" plus "Transmission Mounting Brackets", and steadies it with a "Rear Transmission Stabilizer" and a "Front Stabilizer Bar". Potential Motorsport does not separate engine and gearbox mounting at all but supplies a "4x K-series Billet engine mount kit 70A rating (fast road)" for the whole transverse unit; the 70A figure is the rubber hardness of the road specification.
Status: SUPPORTED · Confidence 66%
The shift mechanism has to be rebuilt. Mini Tec names the shift mechanism as one of the areas every Honda kit requires modification to. Potential Motorsport sells a purpose-built answer, the K Series Billet Shifter at GBP 380, described as "the go-to shifter for our K swap Minis", designed "to work with both factory and aftermarket shifter cables", with an integrated billet arm for adjusting gear spacing, a stainless steel lever with the ball seated in a spring-loaded brass socket, and full adjustment in height and rotation. Nothing was found on the tunnel opening, on cable routing through the bulkhead or on the pedal box relationship for the front-transverse route.
Status: SUPPORTED · Confidence 68%
No reliable combination-specific information found on clutch, flywheel and release actuation in this combination.
Status: OPEN
No combination-specific automatic transmission solution documented.
Status: NOT_APPLICABLE
No combination-specific automatic transmission solution documented.
Status: NOT_APPLICABLE
No combination-specific automatic transmission solution documented.
Status: NOT_APPLICABLE
No combination-specific automatic transmission solution documented.
Status: NOT_APPLICABLE
No combination-specific automatic transmission solution documented.
Status: NOT_APPLICABLE
Both kits include purpose-made driveshafts, and both makers rate them at 400 hp. Mini Tec supplies "2 Custom Hybrid Chromoly 400hp Axle Shafts", installed with "Complete Inner Honda CV Joint Assemblies, and Complete Outer Mini CV Joint Assemblies" - i.e. the Honda joint at the gearbox and the Mini joint at the hub. Potential Motorsport supplies "Billet one piece drive shafts" with "Heavy duty outer CV joints" and advertises "beefy 400hp rated drive shafts". The same maker's own site publishes a customer statement about earlier kits from elsewhere - "drive shafts popping out, CV boots tearing apart" - which places driveshafts among the known weak points of this conversion.
In the front-transverse layout the differential is inside the Honda transaxle and no source names a separate differential part - consistent with both kits being sold without a gearbox. A limited-slip differential appears only in individual builds: one Clubman is described as having a "limited-slip standard box" and one Z Cars car as having a "6 speed LSD gearbox kit". A separate differential exists only on the all-wheel-drive route, and that route is transferred rather than documented for the K-series: Mini Tec's AWD subframe kit MT361000 uses the rear differential and propshafts of a 1996-2001 Honda CR-V and the maker's own compatibility sentence is "Any Honda B-Series engine will fit the CR-V transmission". The one documented AWD Mini with a K20A is built on "Mini Tec AWD B-Series front and rear subframes", so the K-series case rests on a B-series product - uebertragen, not proven.
Status: SUPPORTED · Confidence 60%
Only one publisher documents this. The Mini Tec manual requires: "Change your fuel pump to one that ranges from 32 to 48 PSI. A return line will be needed on certain models that do not have them. An inline fuel pressure regulator will also be required to set your system at 45psi." The same maker lists the fuel system among the areas that have to be modified for every Honda kit (1Q).
Status: SINGLE_SOURCE · Confidence 46%
Two documented solutions and one clear warning. Mini Tec accepts either a "Modified Honda Civic radiator or Mini Tec's MTK aluminum radiator kit (#511400)" (1Q for the part number). Potential Motorsport includes a "Custom Aluminium Radiator" in its kit. That the radiator is the real bottleneck rather than a detail is stated by a forum member: "you would struggle with room for a radiator. It's really tight to fit a radiator with a b series engine so it would be a lot harder with a k series engine".
No reliable combination-specific information found on intercooler and charge piping in this combination.
Potential Motorsport includes a "Potential Motorsport custom stainless exhaust manifold with 2.5" V-Band collector" in its K-series kit. Mini Tec does not supply an exhaust and names it as one of the areas the customer has to modify: "all the Honda engine kits require modifications to the inner fenders, exhaust, fuel system, shift mechanism, wiring, firewall, steering, brakes". No source describes the routing behind the manifold - past the subframe, through or around the inner wing, or the position of the silencer.
The engine keeps Honda control. Mini Tec lists "Modified Honda ECU or engine management system" and "Honda engine, ECU, and dash wiring harness" as parts the customer supplies, and names wiring as one of the areas requiring modification. Potential Motorsport explicitly excludes it: the kit is sold "minus engine, gearbox and no electronics/wiring". On the harness itself the K-series specialist Hondata documents the general swap wiring: "you need to K20A engine wiring harness. This harness plugs straight into the ECU A and B connectors, leaving only the ECU E connector and the engine harness 20 pin connector for you to wire in", with power required at pins 9, 14 and 20, and four warnings that apply to any K swap - a main relay must be used, power must never be wired to the ECU's E1 fuel pump relay output, the ground from the engine harness to the intake manifold is critical, and OBDII and the multiplexer functions have to be switched off.
Only one publisher says anything here: Mini Tec lists an "Electronic speedometer" among the parts required for the conversion, which means the mechanical Mini speedometer drive is not carried over (1Q). Nothing was found on the immobiliser, on the transponder in the Honda key, on the rev counter signal or on the remaining warning lights.
Status: SINGLE_SOURCE · Confidence 40%
Both kits replace the front suspension rather than adapt it. Mini Tec supplies "Upper Suspension Arms", "Adjustable Lower Suspension Arms", "Extended Steering Arms" - the maker's stated reason is "better control at high speeds" - and a "Lower Cross Member" described as a detachable bar for extra strength; the manual additionally requires coil-over shocks (#511200), a front disc brake system "such as; Mini Tec's Superbrakes, Mini 8.4" disc brakes", and wheels with a -7 mm offset to the outside or 1 inch spacers for turning clearance (1Q for the part number). Potential Motorsport's kit contains "2x custom top arms", "T45 on-board adjustable bottom arms (rose joint)", a "Heavy duty pre built complete Upright pair", "Custom made compression and rebound adjustable coilover pair with springs", "252mm directional cooling vented and grooved discs and 4 piston billet big brake kit" and a "Wider track steering rack with UJ - Stock ratio". The Z Cars cars are braked differently again: 256 mm grooved and vented discs with Wilwood calipers front and Ford Sierra Cosworth calipers at the rear.
Status: VERIFIED · Confidence 82%
The recurring theme in every source is that this is not a bolt-in conversion. Mini Tec states it plainly: "The K series installs are quite extensive - all the Honda engine kits require modifications to the inner fenders, exhaust, fuel system, shift mechanism, wiring, firewall, steering, brakes", and right-hand-drive cars need additional firewall work to clear the steering rack. Space is the concrete problem. A forum member warns "you would struggle with room for a radiator. It's really tight to fit a radiator with a b series engine so it would be a lot harder with a k series engine", and the same thread shows the two ways out - a 90 mm extended front end, or moving the firewall, which one member proposes as four inches back and another calls "quite drastic", with the consequence that pedals have to be replaced and the steering repositioned. Kit quality has been an issue: one builder on a US forum warns about quality control problems he experienced with kit manufacturers, and one UK maker's own site publishes a customer account of earlier kits with "drive shafts popping out, CV boots tearing apart". Cost is repeatedly named as the reason conversions fail before they start - "Christ those subframes are expensive!", the observation that finished cars sell for USD 20,000 plus, and the advice that "there are plenty of cars already done with the vtec conversion be cheaper just to buy one". No source in this run reports a completed conversion that was abandoned or reversed.
Status: SUPPORTED · Confidence 74%
No reliable combination-specific information found on the approval prospects for this combination in Germany.
Status: OPEN
Germany, as of July 2026. No German source was found for exactly this combination - K20 or K24 in the Classic Mini; the following information is general and comes from two inspection institutions. TUV SUD states that the Betriebserlaubnis may lapse if modifications have been made "that may be expected to endanger other road users", and that a modification report under § 19 StVZO "may be required even" where an ABE, EC marking or Teilegutachten exists; engine tuning is expressly named as requiring inspection. TUV Rheinland describes individual approval (Einzelabnahme) under § 21 StVZO as the route for "vehicles with conversions for special purposes" and points out that the expert must "carry out all necessary tests and examinations himself" and that no registration is possible without a positive report. On the German conversion scene: there are businesses that get Honda engines registered in the Classic Mini - one German supplier advertises "All our conversions are TUV approved!" - but that supplier works exclusively with D16, B16 and B18, i.e. a different engine family. A German-language Mini forum notes that registration has become more expensive because nowadays "everything is only registered (if at all) with a road test by the inspector"; that thread also deals with B16 and B18 and does not mention K20 or K24.
Status: SUPPORTED · Confidence 56%
https://www.minimania.com/part/MT510000/Vtec-K-Series-Honda-Engine-Conversion-Kit-For-Mini-Cooper | https://www.minimania.com/part/MTK20A3-2/Vtec-Honda-Mtk-Engine-Package | https://www.minimania.com/part/MT361000/Vtec-Mini-All-Wheel-Drive-awd-Subframe-Kit | https://potentialmotorsport.com/shop/conversion-kits/k-series-kit/ | https://potentialmotorsport.com/package-lineup/ | https://potentialmotorsport.com/shop/short-shifters/k-series-billet-shifter/ | https://www.gracing.de/mini-tuning/
https://www.youtube.com/watch?v=-KFfOHdH5w0 | https://www.youtube.com/watch?v=MAPjehW7hdM
https://www.minimania.com/Honda_K_Series_Engine_Conversion_for_Classic_Mini | https://www.theminiforum.co.uk/forums/topic/271224-k20a2-mini/ | https://www.theminiforum.co.uk/forums/topic/323200-k20-or-b18c/ | https://grassrootsmotorsports.com/forum/grm/how-difficult-is-a-honda-swap-in-a-classic-mini/179798/page1/ | https://engineswapdepot.com/?p=22863 | https://engineswapdepot.com/?p=65086 | https://silodrome.com/mid-engined-mini/ | https://www.ukminis.co.uk/competition/1998cc-z-cars-k20-vtec-mini-flash | https://www.thatsclassic.co.uk/for-sale/mini-k20-powered/ | https://www.autoevolution.com/news/insane-1971-k-swapped-mini-clubman-is-an-absolute-corner-ripper-174742.html | https://www.hondata.com/tech-k20-swap-wiring | https://www.mini-forum.de/threads/55452-Kosten-Umbau-auf-Honda-Vtec | https://www.tuvsud.com/de-de/branchen/mobilitaet-und-automotive/tuning-eintragungen-und-aenderungsabnahmen | https://www.tuv.com/germany/de/einzelabnahme.html
32 findings from 21 hosts, of which 27 reachable and 5 unreachable (16vminiclub.com twice 403, k20a.org twice 402, pistonheads.com returned an empty page). 22 findings are used in substance and cited in fields; they are spread across 13 publisher keys. The record is carried by two mutually independent kit manufacturers on two continents - Mini Tec, distributed via minimania.com in the USA, and Potential Motorsport in the United Kingdom - supplemented by two build-report portals (engineswapdepot.com, silodrome.com), one Mini forum, two British scene sites, one engine management manufacturer (hondata.com) and four German-language findings from four German publishers (tuvsud.com, tuv.com, gracing.de, mini-forum.de), all four reachable, none of them combination-specific. Two notes on the counting, so that the figure in the check report is not misread. First, the checker normalises host names to the last two name components, which is why theminiforum.co.uk, ukminis.co.uk and thatsclassic.co.uk all collapse to the key co.uk - three genuinely different operators appear there as a single publisher. Twenty-one hosts thus become 19 publisher keys. No field with status VERIFIED or SUPPORTED rests on those three pages alone. Second, manualslib.com is not to be read as a second publisher: it holds the same Mini Tec installation manual as minimania.com, is to be counted once as a document, and is used solely for one part number, which is marked (1Q) in the field text. Ten findings remain uncited: the five unreachable ones, the two YouTube links (per § 5 not technical evidence), stevestonmotorco.com and carscoops.com (both deal with the D and B series respectively, i.e. a different engine family) and thatsclassic.co.uk, whose statements are covered by more reliable findings on the same Z-Cars conversion. Sixteen search runs; every finding used was opened and read.
Type
Power
Torque
ECU