This article is courtesy of MiniWorld – http://miniworld.co.uk/
Author: Rob Hawkins

ZCars Modified Mini Saloon

Fast Minis generally have some level of compromise and the old saying that you dont get something for nothing is certainly relevant. A 1380cc A-series or a big bore turbocharged conversion for instance, will cost around £2,500 – £3000 to build, will produce in the region of 120 or more bhp and can be a handful under hard acceleration when the torque steer kicks in. Reliability, generally, becomes an issue if you push the power output closer to 150bhp or beyond. Popular FWD engine conversions including the Rover K series, Vauxhall XE ‘red top’ and Honda VTEC usually offer better performance than the A-series, and with greater reliability, but costs are similiar and the handling, braking and controllability have to be matched with uprated components. Its not merely a case of dropping a big engine under the bonnet! It is complicated to build a well-balanced Mini with significantly more power than a tuned A-series can offer, and Hull-based ZCars, with its mid engine conversions that cost a minimum of £3,800 for the kit (less engine and gearbox), is evidence of that. With the first Zcars mid-engine conversions using the 999cc Yamaha R1 and more latterly the 1299cc Suzuki Hayabusa motorbike engines, these early cars were targeted at the Mini racing and track day market. Whilst some of these cars could be legally driven on UK roads, they were designed for track use. Even when ZCars started to introduce the more civilised, high-revving Honda VTEC engine, the racing and trackday image stuck, further aided by the launch of the spaceframe Sprint and Monte Carlo kits with GRP bodywork and limited Mini parts. These powerful Minis are well suited to race circuits but we decided to see if such cars really are that straighforward to drive on the public highway. The car in our photographs is an early conversion, completed some seven years ago, and still with the original owner, David Rose. He initially started a Watsons Rally FWD conversion, but switched mid-way to ZCars.

The conversion was completed at ZCars’ East Yorkshire-based workshops and is the only example built in-house with a honda integra 1.8-litre iVTEC engine (also known as the B18) and five-speed manual gearbox. Several customers have completed their own conversions using this engine. In brief, a ZCars mid-engined Mini conversion entails removing the rear subframe, cutting away the boot and rear floor and installing a new tubular framework with trailing arm suspension, coil-overs and suitable engine mounts. At the front, ZCars can supply its own tubular subframe, to replace the Mini’s which features inboard coil-overs and lower wishbones with an upper arm and adjustable tie-rod style upper link. The front hubs can be taken from a post-1984 Mini, allowing a range of Mini brake disc and caliper combinations, or aftermarket components. At the rear, the hubs are made in-house at ZCars and equipped with machined Mazda MX-5 solid discs and Sierra rear brake calipers (including the handbrake mechanism). This particular conversion also has features taken from the New Mini, such as a full-length glass sunroof, which was fitted by David. Inside, the stalk switches on the steering column and the toggle switches on the centre console are all New Mini items, along with the front seats (also fitted by David) and instrument binnacle in the centre of the dashboard. Some parts have been painstakingly handmade.

ZCars Steve McManus explained that he’s particularly proud of the Alpine head unit surround on the passenger side of the dashboard which he carefully made from sections of folded aluminium before it was TIG welded together. Several components have been hidden away, such as the sound systems amplifier and subwoofer, which are housed in the engine bulkhead panel behind the seats. Kent-based car audio specialist, EnigmaCar, has fitted all of the in-car entertainment components inside this Mini and they also fitted the headlining and installed a stalk switch-operated cruise control. Top of the list has got to be the self-opening boot lid, which opens partially at a certain temperature to facilitate ventilation of the hot air in the engine compartment. With the engine in the rear, heat can be a problem, so the lid opens automatically to let the hot air escape. Everywhere you look on this Mini, there are trick features that can be incorporated in many other cars. For example, there’s no ignition key, just a fob to switch off the immobiliser, a kill-switch for the battery and a start button. The indicators are wired up to LEDS on the dashboard that flash at the same time. At the front theres a bank of six lights, some of which are daytime running lights (DRLs). The neat features on this Mini dont detract from the overall classic styling. Twin aluminium tanks have been fitted with just enough space around the engine. Due to heat soak, theyve now been lined in heat shielding. Overall this car looks like a typical retr0-styled Mini with a Mk1 grille, albeit on steroids once you clock the 8×13 inch wheels and rollcage, interestingly the bumpers are fixed to a lip, which is bolted to the shell, so they can be quickly removed for a de-bumpered appearance. Ive driven and been inside several Minis converted by ZCars and, whilst they have been fun to drive and incredibly fast, the harsh ride quality, noise and heat hasn’t made them as practical as any FWD Mini.

Sliding into the New Mini Seats and wrapping an inertia-reel seatbelt around me was the first major difference I noticed over previous ZCars conversions. Most of them are equipped with bucket seats, harnesses and a removable steering wheel. Such a racing set-up is essential for track use but an everyday road car can have normal seats and a retractable belt although this one does have additional mounts for harnesses. After running through the start sequences, which involved flicking the kill switch, pressing the key fob into position and then pressing the star button, the 200bhp integra engine was ticking over behind me, A blip of the throttle produced a civilised growl with a slightly tappet like rattle that instantly made me think of a A-series. I’d been warned the gear change on this car was a little sloppy. It is controlled via two cables and, whilst is felt like stirring soup when I waggeld the gear lever, there was nothing wrong with each selection, precise and positive. Setting off, the clutch was relatively light and the engine sufficiently tolerant to not need a specific level of revs to avoid stalling. The car drive train used here delivers far better tickover torque than a sports bike engine. This in turn, deals with low-rev starts more smoothly and with lower rpm.

There seemed to be nothing challenging about this car, so far, so good. Out on the open road, I had the opportunity to work through the gears and get to grips with this Mini. Steve had warned me that the non-servo assisted Wilwood four-pot front and Sierra rear calipers feel a little wooden, but seem to work well. He wasn’t wrong. The rearward weight shift under acceleration improves traction at the driven rear wheels – the opposite to a front-drive car, which lightens at the front and loses traction capacity under acceleration. At one point I was driving slowly through a village when the open road appeared ahead, along with a national speed limit sign. In my rear view mirror were two motorbikes, waiting patiently, I was in second gear and eagerly awaiting the chance to floor the accelerator pedal. When it was safe to do so I planted it hard to the floor. The VTEC responded in an instant and I kept my eye on the road, whilst glancing in my rear-view mirror and at the tacho in the center of the dashboard. At 8,000rpm I grabbed the third gear and glanced in my rear view mirror. The motorbikes had kept up but, as I approached the crest of a hill, I knew there were several corners awaiting me and I would be no match for them, so I waved them through. After a few minutes driving this Mini, my confidence was growing. With a mid-engined layout. I was aware I couldnt drive through a corner in the same manner as a FWD Mini. A short wheelbase like the Mini’s can exaggerate the symptoms of over or understeer. I decided to wait until the wheels were straight before accelerating hard again and realised I had negotiated each corner at a faster speed than most FWD Mini but with less drama.

“Had I been in my old 1975 Clubman, I would have approached the corner in a similiar manner, but chosen a gear with higher revs to allow me to feather the throttle and find the point where the car stars to understeer. At the point of winding out the steering, I would be back on the throttle and anticipating understeer. I returned to ZCars having discovered several points about this mid-engined Mini. The ride quality is good enough for it to be driven regularly on the road. Its undeniably fast, but its also civilised enough to cruise along in fifth with a mere 3,000rpm on the tacho at 60mph. Owner David Rose explains his reason for the build: “Im getting too old for raw, uncompromising baseball-cap-wearing nonsense. I wanted a refined Mini and nobody was going to say it couldnt be done”

Technical Specification

Engine:

200bhp Honda 1.8-litre B18 iVTEC from Honda Integra, standard multi-point fuel injection, electric fuel pump, in-line filter. K&N 57i induction kit, stainless steel exhaust manifold, single silencer system, front-mounted aluminium radiator, mechanical water pump, Honda ECU.

Gearbox:

Honda Integra five speed manual box, custom ratios, cable change, Fidenza steel flywheel. Exedy clutch, Honda Integra LSD

Brake:

Dual-circuit non-servo assisted, single brake master cylinder, copper pipes, braided steel flexi-hoses. Wilwood 4-pot front calipers, 258mm vented, drilled front discs. Mazda MX-5 machined solid rear discs. Sierra rear calipers, handbrake mechanism.

Suspension:

ZCars front, rear solid mounted tubular steel subframes. Front post-1984 Mini hubs, ZCars inboard coil-overs, lower wishbone, adjustable upper arm and tie-rod. Rear: ZCars trailing arms, outboard mounted coil-overs.

Wheels/Tyres:

8×13-inch Minilite-style alloys. Continental 195/45×13 tyres.

Interior:

New Mini front seats, inertia-reel seatbelts, MSA-compliant Zcars integrated rollcage as part of rear engine conversion, black carpets, Sparco three-spoke suede-trimmed steering wheel, New Mini stalk, toggle switches, steering-column-mounted Koso digital speedo, Pro-Comp 10,000 rpm tacho/coolant temperature gauge, ATL fuel gauge, steel centre console/race tunnel. Mini vinyl covered door cards, electric window conversion, Alpine head unit, bulkhead-mounted amplifier, subwoofer-footwell-mounted speakers.

Exterior:

Replacement Mini saloon bodyshell, paint two-pack Old English White (WT3), gloss black roof, Curley Specialised Mouldings Miglia-style carbon fibre wheel arch extensions. New Mini full-length glass sunroof, twin custom alloy petrol tanks, filters. thermostatically controlled partially-opening boot lit for engine cooling, halogen deadlights, four additional spotlights, clear front indicator lenses, Mk1 chrome front grille, bumpers, chrome-door mirrors.