Tuning Guide to the Lotus Elise

LOTUS ELISEIt’s difficult to imagine the performance car scene without the Elise. Go to any track-day and you’ll see swarms of them buzzing around, darting in and out of tin-tops as they mix it with the inevitable Se7ens; Se7ens that owe their design to Lotus. For the second time in the twentieth century, Lotus went back to what they knew and created the blueprint for a driving machine in its purest form.

No trickery, just an ultra-stiff, ultra-light aluminium chassis, a pretty plastic body and the fruit of Lotus’ labours in the suspension set up, making that humdrum Rover lump’s 118bhp perform like a Grand National winner. Yet the

Elise had far broader appeal than its predecessor; it suited those who wanted something that actually looked like a car, and those who wanted a roof that didn’t require a troop of scouts’ tent erecting skills. Now the earliest Elise is past its 10th birthday, prices have tumbled to a more affordable level, putting it slap bang in the price bracket for many people looking to buy a second car for track-day frolics.

Obviously for your £10k you won’t be driving into the sunset with an all singing all dancing 111R or Exige. And 118bhp hardly gets close to making full use of the Elise’s reserve of prowess. There’s so much room for improvement, and there’s

so much temptation from the tuning industry that’s built up around the Elise that you won’t have finished your first track-day before your mind’s bubbling with ideas for more power, bigger brakes and sharper suspension. Or you might have bigger, bolder plans.

Lotus chose the Rover K-series but that doesn’t mean you have to. There are a number of alternative engine, all capable of producing superbike worrying performance. But with so many possibilities, how do you choose? We spoke to experts and owners to bring you all the information you need to make your Elise go faster, handle better and stop quicker than the rest.

THE ELISE WAS BRED FOR THE TRACK, BUT BUILT FOR THE ROAD – FEW CARS ARE AS FOCUSED AS THE NIMBLE LOTUS. ED HALL FINDS OUT HOW TO CREATE THE ULTIMATE TRACK-DAY TOY

TUNING GUIDE

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BrakesUpgrades start here, predictably with higher temperature pads. For fast road and the occasional track-day use the Mintex 1144, for half road and half track use the Pagid RS42, and for mainly track use fi t Pagid’s RS14. Unfortunately if you own an early car with aluminium brake discs you’ll need to make

TransmissionOften overlooked, a better set of gear ratios can make more of a difference than a tuned engine – the closer ratio gearbox from the 111S is the one to go for. AP do a mildly upgraded clutch that makes sense too. And for over 160bhp, a Quaife ATB will stop wheelspin out of corners.

the retrograde step to steel discs – you can’t buy original pads and the available ones aren’t great.

AP discs are the next stage, followed by an AP four-pot kit, though that’s often a bit of an expensive overkill for the road. As usual, braided lines and top spec fl uid are musts.

SuspensionThe handling prowess of the Elise is something that’s often taken for granted – after all, that’s why you buy the car. But more often than not a ten year-old Elise can be a long way from its prime. Spending time and money on the suspension will make you go much faster on the track than engine mods.

Geometry is absolutely critical to how they drive and needs professionally setting up, even if the car’s just rolled out of the factory. The most common failing of an ageing Elise is knackered dampers. Graham of Plans Motorsport fi nds it astonishing

how many Elise owners will spend a fortune on induction kits etc yet drive around with shot suspension. To transform your S1, throw away those clunky Konis and upgrade to an S2 Sports Bilstein springs, dampers and top mounts. Don’t bother with the cheaper kits, the Lotus/Bilstein package only costs £5-600 and is perfect for fast road and occasional track-day use.

The next mid-budget upgrade is a set of Nitrons. They’re popular with good reason – they really work. For £1146 you get single adjustable aluminium monotube dampers and springs, but you need

to consider fi tting Nitrons as part of a package with upgraded anti-roll bars to make the best of them. Lotus or Plans can both help here.

If money is no object then Ohlins are the ultimate package. The two-way kits, including springs, are available in 36mm and 46mm, costing up to £2.5k.

Bush upgrades are well advised; particularly at the rear where compliance allows toe changes. Avoid solid Nylatron bushes as they wear pivots and fulcrums. Instead go for Powerfl ex black.Contact: plansmotorsport.com, 01483 548545.


TUNING GUIDE: LOTUS ELISEPPC TECHNICAL


EngineDespite getting a tough time from everyone because of head gasket failures, the K-series can be a tough, reliable engine that’s easily tuned for power. An induction kit and noisy exhaust are always the first modifications owners do; they sound good but only really start to become necessary once you’ve got busy inside the engine.

If you’re planning further work make sure you buy a 4-2-1 manifold to match the exhaust as the stock part is pretty awful. 4-1 manifolds are available but tend to move the power rather high in the rev range. Of the manifolds available, EBD and Janspeed are both recommended, though it’s the Eliseparts one that comes out top as it’s slip jointed to the system rather than solidly jointed which stops it cracking.

Changing the standard 48mm throttle body with a larger one is the next change most make. The benefits are twofold; changing to a 52mm body will release 2/3bhp on a standard engine and maybe 5bhp or more if it’s had cams and headwork, secondly the bigger

throttle will not have the part hemisphere that obstructs airflow at low throttle openings. It’s there so your gran could drive it through town without kangarooing, and although removing it doesn’t actually give any more power, subjectively it makes the car feel snappier with a sharper response. Don’t go above 52mm though – rolling road tests have shown that this will actually reduce power at the top end.

Camshafts are the next stage as they’re quite soft, however changing the cams without any head work or bigger valves will only serve to move the power band up the rev range, losing torque lower down. A set of Piper BP270 cams will set you back around £440, which should bring 135bhp. Dave Andrews of DVA Power can’t emphasise enough the need to buy vernier pulleys and time the cam in when changing cams; they can be as much as 16˚ or one tooth out.

To gain further power throughout the rev range and crucially claw back that low down torque you need to improve the volumetric

efficiency of the head by porting and ultimately fitting bigger valves. Apart for the big of port and large of valve VVC engine the porting and, to some extent, the valves were originally designed for a 1400cc capacity so become a real limiting factor. Standard valve sizes can be enlarged from 27.5mm (inlet) and 24mm (exhaust) to 29.5/26mm using the standard head inserts and Paul Ivey valves.

Interestingly, up to this point, which should be in the region of 150bhp, the standard ECU should cope, compensating to suit the engine’s new characteristics. It’s best to get a air/fuel ratio meter and get the car on a rolling road to make sure it doesn’t lean out at higher revs – if it does, the trick is to remove the fuel pressure regulator and squeeze the spring in a vice between two sockets to give half a bar extra fuel pressure.

What you can’t do is run any wilder cams than a 270 because the valve overlap would cause pressure pulses within the inlet manifold, fooling the MAP sensor

Top right: The K-series is light and can be powerful and reliable.

Middle right: For over 170bhp rebuild with forged pistons.

Bottom right: Lotus offered the K-series with 118-190bhp.

Main image: The Elise was everything Lotus does brilliantly.



into telling the ECU the throttle was being blipped when in fact it was trying to idle. In short, it’d run like a bag of shit.

Much beyond 150bhp programmable management is necessary, allowing EP285 cams, which together with a VVC inlet manifold will give a reliable 165bhp. This is a nice figure to stop at – beyond this everything starts to become expensive and long-term reliability is called into question. Over 170bhp will break the pistons’ ring lands, so you’ll need forged ones.

Rods, although very strong (the earlier rods are the strongest), will need their little ends bushing for a fully floating, circlipped gudgeon pin. Then there’s the considerable expense of throttle bodies, and as Dave Andrews says, once you’ve spend all that money for 170bhp, you might as well go for 220bhp.

Alternatively you could plough your cash into a different engine – one with far more power potential. If you fancy that, read on ...Contact : dvapower.com, 01908 322652.



Engine TransplantsAudi – these days it’s hard to find a car that someone hasn’t shoehorned a VAG 1.8T into and the Elise is no exception. AutoTeknix is the company who’ve pioneered this swap, and for big power figures this is the way to go. Though they’ve supplied parts for this conversion their preferred method is to complete it entirely in house, supplying the engine and box as part of the package.

They use the later 225bhp derivative due its stronger bottom end and offer two power levels; 260bhp and 305bhp at a cost of £11,370 and £14,970 respectively. That seems quite a lot of dosh, however the conversion is quite involved, necessitating minor chassis and subframe modifications, custom made driveshafts and engine mounts.

The VAG management’s junked for an Emerald unit, the gear linkage is custom made and the plumbing is a nightmare.

However, the plus side to spending over 10k is supercar performance figures – using an IHI turbo to give over 300bhp 0-60mph comes up in under 4 secs, 100mph in 8.5 secs and on to a top speed of 170mph. Though the 1.8T is 40kg heavier than the K-series, overall weight distribution changes by only 2%, which, with care paid to spring and damper selection, should be undetectable.

Added to which low lag turbos are used and the ECU’s software combats lag to give an effortless sweep of power without the nasty, laggy delivery reminiscent of turbos from yesteryear that make fast track work tricky and unsatisfying.

As one customer raves, ‘I’ve owned TVRs, 220bhp Sevens and Yamaha R1s, so I’m no stranger to ballistic acceleration, but this is instant warp speed – nothing like I’ve experienced on four wheels.’Contact : auto-teknix.co.uk, 01933 224330.



Honda – Many would argue that this is the engine that always should have gone in the Elise. The VTEC is ideal for track work, being naturally aspirated, revving to 9k rpm and producing 200bhp. Blink Motorsport decided this was the case after seeing numerous 190bhp K-Series engines go bang. They don’t sell a kit but for £9982 they’ll convert your car over 7-10 days.

It’s a completely reversible swap requiring no chassis modifi cations, just new engine mounts, driveshafts, gear change linkage and wiring harness. They source the engines and their six-speed box from UK spec Civic Type Rs. These don’t have the LSD of the Japanese domestic market cars but those units are scarce and the LSD is a little tight for the lighter Elise. Blink use the Honda’s ECU but have it remapped by Hondata to win another 20bhp.

Like the Audi swap, the Honda engine adds a little weight, but

Duratec – New boy on the block of Elise engine conversions, the Duratec has much going for it. Light, reliable and very tunable; a brand new, complete Duratec from Ford costs just £1600. Specialists Raceco (01394 383499) offer a real 210bhp from a standard engine with H/D rod bolts, a ported head, cams and throttle bodies. Bigger cams can be used with pocketed pistons to achieve a reliable 250bhp. You can go up to 300bhp but it gets expensive.

As for fi tting, there’s no one selling a package yet. Steve Williams of SW Lotus has converted his own car that he races in the Elise Trophy. His conversion uses the Elise’s PG1 gearbox with an adapter plate. Steve might consider marketing the conversion if enough people are seriously interested so watch this space...Contact: swlotus.com, 01628 770066·

only 15kg. As the engine’s mounted further forward and lower weight distribution remains the same.

As for performance, 60mph will come up in around four seconds and 100mph in 9.5. Opinion is very much divided over whether the Honda or the Audi make the better conversion; some preferring the rev-happy Honda over the torque-monster Audi for the track.Contact: blinkmotorsport.com, 0870 7417626.

Above: For a reliable, screaming 220bhp, try the VTEC conversion.

Above left & left: A VAG 1.8T in an Elise makes for superbike beating acceleration.


TUNING GUIDE: LOTUS ELISEPPC TECHNICAL


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Tuning Guide to the Lotus Elise