Weight reduction

Original Weight (kg)	Aftermarket product and weight (kg)
Brakes
S1 MMC 2.9 kg/each	EBC 6 kg
S2 Drilled 5.9 kg/each	Ali bells 8.9 kg
Exhaust
S1 Standard 20 kg	S1 Eliseparts Sport Exhaust 25 kg
Door
S2 w/o ali beam complete: 15.1kg
S2 window mech.: 1.375kg		S2 window winder: 120g		S2 mirror fixing triangle: 355g		S2 mirror: 405g		S2 seal window: 302g		S2 inner trim (plastic+leather): 705g

Elise Weight Reduction

S1 Alarm Fob 20 grams

Carbon clams are hideous money compared to the weight saved, and don't save much at all unless they are autoclaved or vacuum formed. Benetec CF Front Clam 4.95 kg Vs std at 15 kg but cost £58k :(

Be very wary of polycarbonate side screens. They are very flexible and, with the roof fitted, flare out dramatically at speeds above 60MPH.

Early rear arch liners are 2.8 kg. Later liners are lighter.

Removing the GRP where the reversing light and fog lights are, along with the grilles and the reversing light saves about 1 kg.

The rubber seals around all four wheel arch liners (assuming you haven't ditched the arch liners) are about 200g each, and most of the boot lid seal can be removed with just token parts left in to prevent rattle giving about 1 kg of saving.

Exhaust Exige/111R Catback: 13 kg. Stage 1: 11.8 kg (saves 1.2 kg). Stage 2: 8.2 kg (saves 4.8 kg). Quicksilver Titanium: 5.2 kg (saves 7.8 kg)

S1 Weight Reduction

-12.5 kg Titanium Exhaust system (std 16 kg vs 3.5 kg)

-12.2 kg Carbon fibre track seats (2.4 kg vs 8.5 kg) x2

-11.2 kg MMC discs instead of iron disks (2.7 kg vs 5.5 kg each)

-8.65 kg Race battery (2.7 kg vs 11.35 kg)

-7.25 kg Lexan front window (5 kg vs 12.25 kg)

-6.8 kg Speedline Magnesium instead of std AWI 5 spoke (25 kg vs 31.8 kg)

-6.55 kg Alloy Fuel Tank

-4.4 kg Carbon fibre fixed seat frames(2 kg and 3 kg vs 0.3 kg)

-4.4 kg Remove the door reinforcement on 2 doors

-4 kg Remove radio and speakers (radio ~1.4 kg speakers ~1.6 kg)

-4 kg Elisparts solid 4-2-1 manifold 6 kg v std 10 kg

-3.695 kg Soft top and mountings (Top 1.807 kg, siderails 1.888 kg)

-3.3 kg Lightweight Flywheel

-2.71 kg Cat Replacement Pipe (flexi stainless) (1.587 kg Vs 4.3 kg) mild steel 1.8 kg

-2.55 kg Lightweight alternator (3.35 kg vs 5.9 kg)

-2.2 kg Billet aluminium crankshaft pulley

-2.136 kg Back window

-2 kg Alu boot lit instead of GRP (Glass Reinforced Plastic)

-2 kg Alu top engine mount

-1.994 kg Rollbar cover

-1.697 kg Heat shield baggage compartment

-1.388 kg Dressed baggage compartment

-1 kg Leather sill covers

-1 kg Carbon fibre steering wheel (1.7 kg vs 0.7 kg)

-0.872 kg Alu ball joint mounts (1.308 kg vs 0.436 kg)

-0.8 kg Footwell divider

-0.6 kg Handbrake and gear stick cover

-0.55 kg Passenger footrest

-0.5 kg Front Mud flaps

-0.4 kg Alarm siren

-0.23 kg Inner Rear view mirror

-1/2 of std Lightweight Starter Motor

-2/3 of std Polycarbonate / perspex rear/side/front screen

Other sources of Information

SteveB

http://www.340r.net/technical/weight/weight.htm

http://forums.seloc.org/t/91178

http://www.elisetalk.com/forums/showthread.php?t=27701

Eliseparts Weight Reduction Section