The first engines in this family, the EF7 series, were designed jointly by Iran Khodro Powertrain Company (IPCO) and F.E.V GmbH of Germany.

[1][2][3] The first phase of the IKCO EF Engines project, the EF7 Dual-Fuel, had an estimated cost of US$80,000,000[4] and aimed to supply 800,000 powertrains by 2010.

Some prominent suppliers for EF engines are INA for critical variable valve timing (VVT) and other mechanical parts; MAHLE, which supplies some integral components of the engine family such as pistons; and Bosch, which supplies the ECU, electrically controlled pedal (Drive-by-wire), and many other sensitive electronic parts.

The EF7s' general structure is similar to the PSA Group's Peugeot TU5JP4, having a 16-valve engine incorporating CVVT technology on its intake valves (IPS type) with a displacement of 1648cc, a bore of 78.560mm, and a stroke of 85mm.

IKCO states that if the engine runs only on CNG, it will not need any special maintenance until 250,000 km (on average).

[8] Alternatively, if the engine runs on both CNG and gasoline, timing belt mileage will increase to more than 250,000 km.

In late 2009, IKCO wanted IPCO to start a project to remove CNG-necessary engine parts.

In September 2010, IKCO announced the design and production of a modified EF7 engine with reduced fuel consumption and air pollution.

To resist the high temperature of engine combustion, about 35 kg of nickel is used in the cylinder block alloy.

[17] 16-valve, DOHC, HLA Tappets, CVVT, MPFI, Catalytic converter 16-valve, DOHC, HLA Tappets, MPFI, Turbocharger, Catalytic converter Dena Plus The EF4 has displacement of 1397 cc with a bore of TBD mm and a stroke of TBD mm.

[21] NIOPDC has been the main sponsor of the EFD engine since it began in mid 2008[21][22] and has poured as much as US$20,000,000 into its development.

[24] Because EFD engines are the first from the EF family to use alternative fuel, they feature many unique, original parts.Iran Khodro and the IP-Co have partnered with AVL to learn to manufacture many of these new technologies.

16-valve, DOHC, HLA Tappets, Direct Injection, Common Rail, Turbodiesel, VGT, InterCooler, Glow Plug, EGR, DPF, DOC 16-valve, DOHC, HLA Tappets, Direct Injection, Common Rail, 2 x Turbodiesel, VGT, InterCooler, Glow Plug, EGR, DPF, DOC