Fresh from creating their brilliant Mini E-Classic electric Mini kit, the boffins at Swindon Powertrain have been turning their attention to the classic 964/993 generation air-cooled Porsche 911 cylinder head. The engine is known as the ‘M64’ in Porsche-land.

It’s a four-valve replacement for the two-valve original complete with two exhaust and two inlet valves. In a nutshell, this lets more air into the engine at higher rpm without compromising the speed of the air entering the engine and leaving via the exhaust at low rpm.

It improves torque greatly at low revs and it redlines higher (12,500rpm rather than 6900rpm) giving a brutal increase in top-end power (circa 450bhp rather than 268bhp). This all opens up the breathing for the Porsche engine and air gas flow is raised by 40 per cent and exhaust gas flow is upped by 60 per cent.

Swindon Power Train reckon that it could produce as much as 125bhp per litre.

CNC-machined from cast from aerospace-grade A356 aluminium alloy the DIY kit costs £35,940 inc VAT.

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