We often are asked about upgrades to increase the power of Lotus Elises with the K series engine.
The exhaust is probably the first item to change. The benefits of a stainless steel sports systems include: not rusting, should sound better; some will produce power increases particularly when combined with other mods. Janspeed exhausts have a good reputation.
Some owners do away with the catalytic convertors. The problem is without a cat an Elise will fail an MOT. To keep things legal, a sports cat is a better route to go - the Janspeed one is meant to release an extra 5 - 6 bhp.
On the induction side, improvements to the air filter and induction box can bring worthwhile benefits. ITG is a well regarded manufacturer and their Maxogen system is reputedly worth an extra 8 bhp.
For Elises with the standard head (i.e. not a 111s with a VVC engine), there are benefits to be gained from making changes to the camshafts, fitting a larger (52mm) throttle body and a gas flowed inlet manifold and/or head.
For VVC engined cars, a Janspeed exhaust manifold, in addition to changes to the exhaust, cat and air induction system can bring good results.
ECU upgrades or re-mapping can produce good results. This is a potentially complex area, depending on the type of upgrade chosen and what's been done to the rest of the engine, and may need rolling road sessions to set the car up correctly.
Our key criteria when recommending upgrades for Lotus Elises, or any other car, are: worthwhile power increases at sensible cost; reliability; proven packages that work first time. A company whose upgrade items and packages meet these criteria are PTP (Power Train Projects). This company has a long history of working with the Rover K series engine and they used to supply the engines to Lotus, developing along the way engine and gearbox packages for the 135 sport, Exige and 340.
We are happy to supply and fit any of the PTP products.