Lotus Exige. Manual

Page 5

Lotus Service Notes

Exige S/C

EXIGE S/C.C - FRONT SUSPENSION - 240R & CUP

Stiffened road springs front and rear are ﬁtted on new Ohlins dampers featuring remote gas reservoirs,

adjustable spring platforms and separate adjustments for compression and rebound damping. The spring plat-

forms allow for lowering of the car to 120/120mm mid-laden ride height for track use, and the 22 compression

and 60 rebound damper settings allow the characteristics to be ﬁne tuned to individual requirements. The gas

reservoir is mounted on the inboard crossbrace of the lower wishbone, and is connected to the damper body

by a steel braided hose.

Compression (bump) damping is adjusted by turning the knob on the end of the gas reservoir canister: Turn

clockwise to increase damping, and couterclockwise to decrease. Recommended settings are as follows:

Road use: 11 clicks from full hard

Track use: 11 clicks from full hard

Rebound damping is adjusted via a ribbed collar below the bottom spring seat: Turn clockwise (as viewed

from below) to increase damping, and counterclockwise to decrease. Recommended settings are as follows:

Road use: 8 clicks from full hard

Track use: 8 clicks from full hard

The motorsport stiffened and 5-position adjustable front anti-roll bar provides further opportunity for ﬁne

tuning. To stiffen the bar, use a more forward hole, and to soften, use a more rearward hole. Recommeded

setting:

Road use: Central hole

Track use: Central hole

Suspension geometry is unchanged - refer to Section TDQ.

EXIGE S/C.D - REAR SUSPENSION - 240R & CUP

Stiffened road springs front and rear are ﬁtted on new Ohlins dampers featuring remote gas reservoirs,

adjustable spring platforms and separate adjustments for compression and rebound damping. The spring

platforms allow for lowering of the car to 120/120mm mid-laden ride height for track use, and the 22 compres-

sion and 60 rebound damper settings allow the characteristics to be ﬁne tuned to individual requirements. On

240R models the gas reservoirs are mounted on the roll over bar backstays, and on Cup cars, on the toe-links.

Each reservoir is connected to its damper body by a steel braided hose.

Compression (bump) damping is adjusted by turning the knob on the end of the gas reservoir canister: Turn

clockwise to increase damping, and couterclockwise to decrease. Recommended settings are as follows:

Road use: 15 clicks from full hard

Track use: 10 clicks from full hard

Rebound damping is adjusted via a ribbed collar below the bottom spring seat: Turn clockwise (as viewed

from below) to increase damping, and counterclockwise to decrease. Recommended settings are as follows:

Road use: 15 clicks from full hard

Track use: 12 clicks from full hard

Suspension geometry is unchanged - refer to Section TDQ. The Track Use Chassis Rear Brace Kit is

ﬁtted as detailed in sub-section DH.5.

EXIGE S/C.E - ENGINE

The 1.8 litre 2ZZ-GE engine with VVTL-i (Variable Valve Timing and Lift - intelligent) of the standard Exige

is ﬁtted with a low pressure Roots type Magnuson MP62 supercharger to provide up to 0.5 bar (7 psi) of boost

pressure. The supercharger is mounted on the left hand side of the block and driven by a lengthened version

of the multirib auxiliary belt. The unit is self contained and features helix twisted rotors to minimise output

pressure variations, and maintenance free gearing and bearings, requiring no externally sourced lubrication.

An integral by pass valve under ECU control, operates to recirculate air from the compressor outlet back to the

inlet under conditions of idle and part throttle to the beneﬁt of economy and quiet operation.

The supercharger is hung off the new intake manifold by two bolts in conjunction with eccentric sleeves in

order to ensure stress free alignment. An alloy bracket supports the nose of the unit to the RH engine mounting

plinth, and a tubular strut braces the intake end of the unit to the clutch slave cylinder mounting point.

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Lotus Service Notes

Exige S/C

Page 6

Supercharger & Ducting

Connection to chargecooler inlet

Connection to chargecooler outlet

New inlet manifold

Chargecooler

inlet duct

Supercharger outlet connector

Supercharger outlet elbow

Supercharger

outlet adaptor

Mounting lug for

supercharger

Fixing point

Swan neck

Chargecooler

to manifold

adaptor ﬁxings

outlet duct

(supercharger

inlet)

Fixed to engine

mounting plinth

By-pass valve

capsule

pl4207ls/pl4209lr

Strut to clutch

Alternator anchor

slave cylinder mounting

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Lotus Service Notes

Exige S/C

Page 8

Air is drawn from the standard air cleaner through the throttle body and adaptor and into the supercharger

axial intake port. From the outlet port on the compressor top surface, the air is directed through a 'U' bend duct

to the LH end of an air/air chargecooler rubber mounted above the engine, where airﬂow gathered from the roof

duct is used to cool the compressed intake charge. The chargecooler uses four rubber bobbins attached to two

mounting brackets themselves secured to the inlet manifold and cam cover. A charge air temperature sensor

is mounted in the outlet tank of the chargecooler. The cooled air exiting from the RH end of the chargecooler

ﬂows via another 'U' bend duct into a cast alloy intake plenum/manifold. The whole intake tract has been kept

as short as possible, and uses large diameter ducting and generously radiused bends to optimise airﬂow and

efﬁciency to the particular beneﬁt of throttle response and fuel economy.

A re-shaped breather pipe is used to connect the crankcase breather spigot to the cam cover and circum-

navigate the supercharger.

On the 240R and Cup cars, a stainless steel 'level one' sports exhaust mufﬂer (LOTAC05334) is ﬁtted to

provide an acoustic enhancement and features enlarged, slash cut tailpipes and a near 20% weight saving

over the standard system. Exige S models use a stainless mufﬂer with a single, oval shaped, tailpipe design.

240R models use 4 standard port fuel injectors together with an additional 5th injector mounted in the

intake end of the inlet manifold. Cup cars use 4 special high-ﬂow port injectors, and Exige S cars retain stand-

ard injectors. The Lotus engine management system is reprogrammed to suit each engine speciﬁcation and

incorporates additional functions to control the ﬁfth injector (240R) and supercharger by-pass valve. The boost

characteristics have allowed the switching point from low to high lift cam proﬁle to be reduced from 6,000 to

4,000 rpm (at normal running temperature). 240R models use a mechanical cable operated throttle body,

whereas the Cup and Exige S cars use '06 model electronic throttle. Twin front mounted oil/air coolers are

ﬁtted to all supercharged Exige.

Accusump - 240R & Cup 240

To provide protection against the possibility of oil starvation caused by the extreme g-forces possible with

track use on slick tyres, the 240R and Cup cars are ﬁtted with an Accusump oil storage system.

A 2-litre Accusump reservoir is mounted in the rear luggage compartment, plumbed into the LH oil cooler

return hose at the front of the engine bay, with the connecting hose routed over the RH rear wheelarch. The

device comprises an alloy cylinder divided by a sliding piston, one side of which is connected to the engine

oil supply, with the other containing pressurised air. With the engine running, the cylinder is charged with oil

provided by the engine oil pump, but if the pressure should drop for a short period due to oil pump pick up pipe

exposure during extreme braking or cornering events, the accumulator air pressure forces the stored oil into

the engine lubrication system to maintain continuity of oil supply until normal conditions are resumed.

A one-way valve at the oil cooler connection of the 'T'- piece ensures that the oil discharged from the

Accusump is directed into the oil pump and not the cooler. An Electric Pressure Control (EPC) valve ﬁtted at

the connection to the Accusump cylinder, allows cylinder charging when oil pressure is above 35 - 40 psi, and

cylinder discharging at engine oil pressures below 35 - 40 psi. The EPC is also linked to the ignition switch

such that with the ignition switched on the valve is open to allow oil ﬂow, and with ignition off the valve is closed

to retain oil within the reservoir.

Normal Operation

When the ignition is turned on, the EPC valve on the Accusump is opened, allowing the pressurised oil

stored in the reservoir to ﬂow out into the engine and prime the oil galleries and bearings ready for start up.

When the reservoir has been emptied, the pressure gauge on the end of the reservoir will indicate the pre-

charge pressure which should be 7 - 15 psi.

When the engine is started, engine oil pressure will force the reservoir piston back, such that the reservoir

air pressure gauge will indicate engine oil pressure, with the quantity of stored oil dependent on this pressure

at any one time. With cold oil, 80 psi may be seen, but idling at normal running temperature should produce

around 30 - 40 psi.

When the engine is stopped, the EPC valve closes and a quantity of oil pertaining to that oil pressure will

be retained in the Accusump, ready for re-starting.

Routine Checks

Be aware that the indicated oil level on the dipstick will depend on the amount of oil stored in the Accu-

sump, which itself is dependent on the both the Accusump pre-charge air pressure and the engine oil pressure

when the ignition was switched off.

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Lotus Exige. Manual - part 2