Im considering building a 7th gen for track days, since the 3GFE 6th gen cant be found here. Ive heard that the 7th gen has had bad engineproblems - does this just apply to the 2zz engine or the 1zz engine too?
The 2ZZ was designed for racing with peak torque at high RPM, above 6000 up to 8600.
Lotus tested all small I4 engines and decided to use the 2ZZ engine and xmission for the Elise and Exige. They said it's the most reliable and durable I4, especially for high rev abuses. They added supercharge to boost HP.
I have a GTS 2ZZ auto with 320K miles with years of abuses. It still runs perfect with mostly original OEM components. never had problems. Still cruises fine at 90-100 MPH on long trips.. My friends who drive Porsche, Ferrari, BMW, MBZ all prefer to cruise fast in this car to their own expensive wheels. They say the car runs fast but feels slow and stable.
There was a few cars here in Australia that ran 2ZZ engines very successfully. Osborne Motor Sport ran a pair of them at heaps of events including the Bathurst 24 hour and various other endurance events.