Lotus Exige S or Sport 350 Supercharger upgrade kit
The factory fitted TVS 1320 supercharger is on the limit of it’s operating efficiency window on the V6 Exige. On a 25.7 deg ambient air temperature day we logged the intake air temperatures and pressures of a stock V6 to find they regularly hit over 90 degrees celsius and peaked at 97 deg within 2 laps. Without any provision for a cooling system this means the engine management system is reducing engine power through reductions in ignition timing and addition of extra fuel just to keep everything safe. Any further reduction in pulley size would generate some extra boost pressure but even more heat meaning the performance gain will be very short lived and potentially harmful to the engine.
So to solve this common problem Simply Sports Cars, in conjunction with Harrop Engineering who manufacture the Lotus OEM TVS1320 supercharger, have developed a direct bolt on replacement using the TVS1900 charger. This charger has a significantly higher capacity, allowing us to use a bigger pulley to produce higher pressures and achieve lower intake air temperatures than the OEM set up.
Lotus Evora supercharger upgrade kit
If you are interested in upgrading the supercharger on the engine of your Evora we have variations of our TVS1900 kit that can be adapted to suit. Contact our team directly using the form on this page to talk through the various options available. We will need to know the series, year model & intended application/s to be able to assist providing the right solution for you.
There are two upgrade kits available;
- Non-Charge cooled
- Harrop TVS1900 Supercharger
- CNC machined inlet manifold and throttle body adapters
- Correct length drive Belt
- SSC CNC machined MAF sensor mount
- Optional Air intake with SSC Silicone, Aluminium Pipe & HKS performance air filter
- Optional OBDII Flash tool to update the tune
- Charge cooled
- A housing for the TVS 1900 supercharger, developed and manufactured by Harrop, with fully integrated charge cooler, enabling a superbly packaged installation
- Charge cooler radiator & header tank with all associated installation plumbing & brackets
- Air induction kit featuring a CNC machined and welded MAF sensor mount and high-performance HKS filter in a custom carbon fibre housing, with all associated pipework, brackets and clamps
- New high-grip Gatorback drive belt
- Optional revised engine tune with excellent drive-ability throughout
There are a lot of other available variations of this kit depending on your intended application.
Use the contact form to discuss options & get a quote including installation.
How much power does this supercharger kit make?
It’s the obvious question we get asked over and over and it’s one for which there really shouldn’t be an answer with a single number. We don’t often publish power numbers or dyno plots from our products because the inconvenient truth of the dyno chart is that it rarely represents a real world environment, where your car spends all of it’s time. In order to communicate the real and functional gains our kits provide, we truly believe that to paint the full picture of it’s performance and technical merits of our design, much more than a line on a graph or a single HP number is required. After all: there are any number of dyno conditions which even OEM manufacturers can combine together in order to provide ideal circumstances to produce an impressive number on paper.
What does the performance improvement look like?
Bearing in mind that the image below shows kW at the hubs, the optimist in us would add a generous 20% drive train loss and announce that we have made 263.5kw(353hp) at the hubs into 329.37kw (441.7Hp) at the crank – 28% more than stock. On the other hand, the much more conservative side of us would use a more realistic end of the scale at 15% drive train loss, giving us 309.4kw (415Hp) – 20% more than stock.
But the harsh reality of any supercharger system is ignored all too easy: they all generate significant heat, and with this heat, the peak power output will inevitably drop. The dyno plot below also shows a consecutive run of our TVS1900 kit showing an increase in intake temperature, and a decrease in power and torque. One of the greatest benefits of replacing the TVS1320 with the TVS1900 on the 2GR engine is that this drop in power is significantly minimised through substantial efficiency gains, allowing higher intake pressures at lower intake air temperatures.
Why not run the OEM TVS1320 with a smaller pulley to increase boost?
As we mentioned above, all superchargers, without exception:
- generate heat when compressing the intake air;
- thus causing an increase in temperature in the fuel/air mixture;
- thereby becoming a major limiting factor in engine performance
The harder a supercharged engine is pushed, the more heat the supercharger will generate. But all superchargers aren’t created equal. The amount of heat generated is directly related to the thermal efficiency of the compressor and how much work it needs to put in to compress the air. Any increase in operating efficiency of the compressor means less heat is generated as an undesirable by-product. Less heat in the intake air means:
- denser air in the combustion chamber, allowing more fuel to be used for a bigger bang which generates more power.
- less tendency for the mixture to pre-ignite in the combustion chamber when it is compressed and heated further by the piston, in which circumstance the ECU will reduce ignition timing to keep the engine safe, reducing power output in the process
Sounds simple enough, in order to determine if more power and more importantly if reliable long-term power was available out of the TVS1320 we needed to determine if fitting a smaller pulley was a good option for generating more boost, and to do that we need to look at the supercharger efficiency map. The image below shows data we collected using extra sensors mounted on a modified inlet manifold fitted to a factory spec Exige S. We have overlaid a scatter of boost pressure (Pressure ratio) VS. Engine/supercharger RPM which shows that the system is operating at the outer limits of it’s thermal efficiency. So although a slightly smaller pulley may be able to produce some more boost pressure to produce more power, the reality is that this is being done at a low efficiency levels meaning that a lot of heat comes along with it. And hence any extra power that it may generate will be even more short lived than the peak power on offer from a factory spec, unmodified Exige S
How does that translate to real world usage?
As the supercharger generates heat through its efficiency losses, the supercharger itself, the inlet manifold and engine rise in temperature, until the system is heat soaked. The data below was taken from a track test of an unmodified Exige S V6 to demonstrate what actually happens out on track where the supercharger is working hard in gear after gear. We can observe that the inlet air temperature peaks at a whopping 95.7 degrees Celcius! At these kinds of temperatures the ECU will be adding extra fuel and retarding ignition timing to keep everything operating safely. Without being able to log engine power out on track, it’s impossible to determine exactly what level of power the car is running at but it’s certainly not close to the advertised peak of 345Hp, and it’s definitely noticeable.
Can a cooler be added?
Cooling the intake air adds even more benefit and adding a cooler to the TVS1900 increases performance even further. We ran the TVS1900 with a cooling system on our Exige Cup R for 2 race seasons. Coupled with the stronger sequential transmission we didn’t explore the upper limits of this set up as the car was built to an endurance specification but suffice to say that with a stronger set of engine internals the performance capable is well above the uncooled TVS1900.
We developed our first TVS 1900 supercharger installation kit for the V6 Exige & Evora more than 5 years ago to give owners huge improvements in power and torque.
Perhaps more significantly, the kit also reduced intake temperatures significantly over the standard TVS 1320, which was already operating at the edges of its efficiency window in the standard car. Cooling the intake air provided even greater benefit, particularly for competition cars in warmer climates. We have successfully run the first evolution of a charge cooled TVS 1900 in our Exige Cup R endurance race car and a number of very high-powered customer cars for the past 4 years, however the 1st generation kit sat the supercharger on top of the cooling system, requiring fitment of the Cup R engine cover and clam mounted rear wing.
In conjunction with Harrop, our long-term partner, we integrated the TVS1900 supercharger with an even larger high density intercooler core which has improved the output of our initial design. An update to our induction kit now also encloses the air filter in a carbon shroud and ducts cool air exclusively from the side air intake giving a further reduction to intake air temperatures.
Significant and consistent power & torque gains over standard on even the hottest day, as shown in the table below
|MODEL|| Power @|
| HP @|
|Factory fitted TVS1320||288||19.79||345||281||6.9||5|
Should you upgrade your supercharger?
At the end of the day you have to do your research and make sure you’re comparing apples with apples when looking at power numbers because anything with forced induction it comes back to managing heat. This is why we believe dyno charts can be misleading and that’s the reason why we don’t like using them. They rarely give the whole story on what temperatures are doing or how the system behaves over time as things get hot. At Simply Sports Cars we endeavour to be as transparent as possible in this regard and design our kits to work in the conditions they will be used in – which is obviously not a dyno environment.