Guide to the 190 Upgrade


The standard 340R engine cam timing, engine calibration, catalyst and air intake system, have been developed and tested after many hours of engine dynamometer and vehicle miles, to comply with the stringent European emissions and noise regulations, but also to meet the Lotus criteria of a strong driveable engine with a progressive response. 

This work has produced a performance and legislative compromise which gives engine emission compliance and an engine with good response, and acceptable power.

In standard form the engine has a maximum power of 177PS.

However the majority of Lotus drivers enjoy a little more performance and noise when they use the car on the track  (or on the road) , and for this Lotus  have produced an upgrade kit to boost the engine performance. Collectively this is known as the '190 upgrade' although each component need not be used, maximum benefit will be derived with the full conversion.

Whilst manufacturer's have to comply with European Type Approval regulations when they manufacture a new car, once these have been delivered to owners modifications can be made which do  not render the car illegal to use on the road, but would not be permitted to be fitted as standard under European Type Approval regulations.

Below, we have examine each part of the 190 Upgrade and comment upon it.

190 ECU

Lotus Part Number : A340M6026S  Part List Price (plus VAT) 349ukp (exchange cost)

This consists of a re mapped engine control unit chip. The 190ECU  has a re-mapped spark map, more mid range spark advance, 8000 rpm rev limit, open loop and re mapped fuelling.

Usually supplied on an exchange basis - you give them your standard chip and they give you a replacement 190 chip. The engine control module is located in the electrical compartment behind the seats.

The 190 ECU can supposedly be identified by a blob of yellow paint on the chip although this is not foolproof as a standard chip can be re written to 190 specification by a Lotus field engineer with his Laptop.

Of all the components used in the 190 upgrade the 190 ECU has the greatest effect on increasing horsepower and torque.

When fitted with the 190 ECU the engine has a more aggressive throttle response and seems to run much richer. An increase in lumpyness of  tickover can also be felt.

Both noise and emissions are increased although Lotus say that when fitted with a catalytic converter the engine should pass the MOT test.

101 Degree Inlet Camshaft Pulley

Lotus Part Number : A340E0011S  Part List Price (plus VAT) 34ukp

This replaces the standard camshaft pulley and increases cam overlap by 4 degrees, it has an extra slot machined in it to give a maximum inlet valve opening point of 101 degrees. This optimizes the output of the engine improving mid range torque.

82 Degree Thermostat

Lotus Part Number : A340K6007S  Part List Price (plus VAT) 4ukp

A lower (than standard) water temperature thermostat allows the engine to operate at a cooler temperature.

The 82 Degree Thermostat  will bring the cylinder head temps down, only by a few degrees, but this small drop improves combustion considerably.

An inexpensive part which is recommended for better engine operation when using the increased horsepower of the 190 upgrade.

Engine Breather System

Hose Kit - Lotus Part Number : A340X6013S  Part List Price (plus VAT) 40ukp

Breather Tank  - Lotus Part Number : A340E6011S  Part List Price (plus VAT) 60ukp

Consists of small bore flexible blue silicone  pipework and a remote  1 litre aluminium catch tank. The breather system allows non combustible gasses to vent from the engine into the catch tank which is open to atmosphere. The catch tank catches all the heavy crankcase fumes which are, made up of water, oil residue,
hydrocarbons, soot and loads of nasties.

As well as being a safety measure, in that it increases the in cylinder detonation limit and allows higher cylinder pressures to be run without detonation,  the breather system allows the engine to operate with slightly enhanced output. Crankcase gasses effectively lower the octane rating of the fuel.

In theory the catch tank should be emptied periodically although many owners have found it to fill at a very slow rate.

It is also common practice for the fuel tank breather charcoal canister and plumbing to be removed. Vent the fuel tank breather pipe from the roll-over valve to atmosphere

Removal of Resonator Valve and Second Air Filter

The air intake hose is fitted within the engine bay pointing down over the exhaust manifold, and in turn is fitted to a large resonance valve.  This device is controlled by the engine management system and is switched on and off during Type Approval drive by tests which take place in 2nd or 3rd gear. When the valve is operated the engine performance is reduced along with the noise . (You can hear it operating - the engine goes quieter and the performance feels strangled)

The valve and air inlet routing is required solely to pass type approval noise tests and is counter productive to normal operation of the engine. For this reason it should be removed (or disabled - see below) and the inlet hose redirected  for best engine performance.

Remove the inlet trunking from its current position drawing air from the exhaust area and move it to the left hand-side of the engine bay taking the air from behind the cold air inlet duct on the side of the car. The roll bar strut is in the way but secure it to this with tie wraps pointing at the cold air inlet.

Also to maximise the engine performance one of the two air filters fitted should be removed (we recommend leaving the one on the airbox on). The airbox and resonator valve locations can be seen in the Technical Service Bulletin section of

A quick alternative to removing the resonator valve is to disable it  as follows (although full removal is preferable for both weight saving and performance) :

Deactivate the resonance valve:  On top of the valve there is a vacuum operated solenoid.  Into the top of this there is a black and white rubber hose.  Disconnect this hose and blank it off (a small greased pop rivet works well as a plug).

The above modifications should be carried out on all cars weather fitted with 190 upgrades or not in order to improve performance.

Cat Replacement Pipe

Lotus Part Number : LOTAC05066S  Part List Price (plus VAT) 54ukp

This is a small section of stainless steel exhaust pipe which allows you to remove the catalytic converter. Removing the standard cat reduces exhaust back pressure.

Benefits of catalytic converter removal are :

  • Reduced weight

  • Increased power and torque

  • Better throttle response

  • More aggressive engine noise

If you remove your catalytic converter be sure to store it in an airtight plastic bag to avoid deterioration  as you may well wish to re fit it when the car is MOT tested.

In other parts of Europe where regulations forbid the use of cars without catalytic converters a Motorsport Cat (Lotus Part Number : A340S6010S  Part List Price (plus VAT) 599ukp ) is available from Lotus.

Sports Exhaust

Titanium Sports exhaust - Lotus Part Number : A340S6011S  Part List Price (plus VAT) 799ukp

SS Competition exhaust - Lotus Part Number : A340S6008S  Part List Price (plus VAT) 379ukp

The standard exhaust is designed to meet Type Approval noise regulations and is both restrictive and heavy (it has a carbon fire effect casing with a heavy noise absorbing needlemat beneath).

To reduce weight, increase power and improve engine sound two sports exhausts are available.

Both sports exhausts have the same  resistance and backpressure with a longer tuned length than the standard exhaust. Both have identical performance and a single outlet pipe.

When used without catalytic converter the exhausts give up to 10BHP advantage at 5500 rpm over the standard exhaust configuration, although peak power remains largely unchanged.

Stainless steel competition exhaust

This is the noisier of the two exhausts and has a round cross section on the silencer. The exhaust is available with increased length connection which negates the need for the use of a cat replacement pipe. A drawback of this exhaust is that its smaller size looks odd when fitted as an increased area of chassis is exposed, also the noise level produced may exceed the maximum allowed at the more sensitive venues.

Titanium sports exhaust

This exhaust is marginally quieter than the competition (but still a lot noisier than standard) This exhaust is very light and has an unusual 'flamed' finish which is a multi coloured bloom which changes with temperature. It has a larger oval cross section silencer and therefore looks more attractive when fitted as is is a similar size to the standard exhaust. A cat replacement pipe is required for those wishing to remove their cat. The only drawback of this exhaust is it's cost (ouch), however it is a real talking point with the public.

Relative weights of exhausts are :

Titanium - 5.65kg

Competition - 6.05kg

Standard - 10.25kg

Also it should be noted that the catalytic converter  weighs around 3kg

Oil Cooler

Lotus Part Number : A340E6009S  Part List Price (plus VAT) 279ukp

With all  this increased power and the prospect of lots of thrashing the car round the track, Lotus recommend the fitment of an oil cooler.

Anyone pushing their car hard should not hesitate to get an oil cooler fitted, the engine is much happier as a result.

This will increase the life of the engine and avoid overheating.

The negative points are an increase in weight and the fact that to fit the oil cooler, which is located behind the front air inlet)  requires the body to be removed to enable routing of the hoses to the engine. Hence fitting is expensive.

All left hand drive vehicles were factory fitted with oil coolers as standard.

Blue Silicone Water Hoses

Lotus Part Number : A340X0001S  Part List Price (plus VAT) 249ukp

These may have increased resistance to high temperature operation (and also look good). Expensive and not essential - mainly cosmetic value.


When fitted with the full upgrade the character of the car changes both from a power and torque point of view (click here to see comparison charts) .

From a auditory point of view there are improvements and drivability is enhanced.

Most owners will find the upgrade an enjoyable experience but, as always, must not be mislead into thinking that this will allow the cars to walk all over a standard vehicle, the better driver may still be able to pilot his standard car quicker round the track, however in a like for like situation the upgraded cars will have the edge particularly on the straights.

Our approximate estimates of additional horsepower available from the 190 upgrade components is as follows:

Item Increase (PS)
190 ECU 13
101 Degree pulley 2
Sports Exhaust with Cat Pipe 4
Breather System 1

Whilst not strictly part of the 190 upgrade some owners may wish to consider fitting the following parts, particularly whilst the body is off for fitment of oil cooler :

Race Battery

Lotus Part Number : A111M6078S  Part List Price (plus VAT) 123ukp

This is a smaller lighter battery also used on racing Elise's. The race battery weighs 6kg against the standard battery's 11kg.

An additional benefit of the race battery's smaller size is the fact that it can be removed via the front access panel should this be required. The standard battery requires the body to be taken off making this an expensive job.

Whilst the race battery's electrical capacity is less than the standard battery, in normal practice this proves not to be a problem. However it is recommended that for vehicles subject to intermittent use (ie most 340R's) a battery trickle charger should be used. A trickle charge socket is fitted to all 340R's for this purpose. (Click  here for trickle charger information)

Alloy Track Use Fuel Tank

Lotus Part Number : A340L0015S  Part List Price (plus VAT) 299ukp

This is a smaller lighter fuel tank.

Capacity is 6 gal (27 litre) compared with 8 gal (36 litre) for the standard steel tank.

Weight is 3.45kg compared with 10 kg for the standard steel tank.

Particularly suitable for track use this tank saves 16kg over the standard tank when full, its capacity is adequate for all but the most excessively long track sessions. However its lower capacity does mean  increased frequency of refuelling making it not very suitable for those using the car without support vehicle.

Goodridge Braided steel Brake Hose Set

Hoses - Lotus Part Number : A340J6000S  Part List Price (plus VAT) 49ukp

Fluid (1 ltr) - Lotus Part Number : A340J6001S  Part List Price (plus VAT) 35ukp

These stainless steel braided brake hoses give reduced brake pedal travel and increased pedal feel.

The Castrol racing brake fluid has increased resistance to boiling and is highly recommended for track use to prevent brake fade. (The editor has used these hoses and fluid with the standard 340R brake pads for 12 months hard track use and never once experienced brake fade)



We reproduce below a list of owners comments on the upgrades, anyone wishing to add their comments please email 











Table of owner's comments




Worth it ?

Glen Harman

"Superior performance...more flexible power output, improved mid-range torque "

"Tendency to burn standard clutch in some circumstances. Increased fuel consumption. Increased emissions"

"Yes, very much so"

Roger Clark

"More midrange torque & a nicer noise,"

"Fuel consumption  seems to be disproportionately worse"

"If it had been fitted at the time that the cars were built as  per Exige option it's worth the money, but now I've got a box of redundant parts".

Mark Spall

"More noise, more responsive, just rips!. Awesome!"


"Tick over was a bit too low - easily remedied though"


"Can't remember how much it was but the answer is yes!."


Peter Crook

"The throttle response is much more aggressive, the engine noise barks like a race car. Like having a different engine"

"Likes a drop of super unleaded, in standing traffic engine fumes are pungent!"

"Yes, makes a great car even better - this is how the car would have been if not for rules and regulations"


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