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Originally Posted by RedVee8
Whats the dfference between a dohc family 2 and an ecotec?
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Family II engines went through various minor upgrades over years. Current versions of Family II include variants made by
Holden - E-TEC/D-TEC DOHC, 1.8 to 2.4 L;
Ecotec 2.0 to 2.4 L -
GM Powertrain Europe (previously Opel Powertrain, part of Fiat-GM Powertrain) and
GM Powertrain (USA);
GM do Brasil - 1.8 to 2.0 L.
They differ in the following aspects:
1. US and European Ecotecs feature all-aluminum engine block. Other versions (as well as Family 1 and Family 0 engines) still use cast-iron cylinder block with aluminum cylinder head.
2. US and European Ecotecs feature DOHC valvetrains with timing chain. Holden and GM do Brazil are using timing belts for both DOHC and SOHC configurations.
3. US and European versions employ roller rocker arms.
4. Europeans only get 2.0 Turbo and 2.2 Gasoline Direct Injection, while Holden rebadged versions get 2.2 L multi-point.
5. Engine control systems are different - Delphi for Holden and GM Powertrain (USA), Siemens for GM Europe and GM do Brasil (?!!).
6. Brazillian versions can run on pure ethanol, pure gasoline or mixtures such as E85 (FlexPower technology).
There are also two other families.
Family 1 - newer more compact block developed by Opel in 1990s. Currently used by:
GM Daewoo - D-TEC/E-TEC/Twin-TEC 1.4, 1.6 L, DOHC, toothed belt, 9.5:1 compression, variable intake geometry
GM Europe - Ecotec 1.4, 1.6, 1.8 L; Ecotec TwinPort (variable geometry) 1.4 and 1.6 L - with lighter block, timing chain and roller cams; recent 1.8 L DCVCP (VVT); knock-sout sensors, 10.5:1
GM do Brazil - 1.0 to 1.8 L, SOHC, toothed belt, FlexPower, 9.5:1, SFI
Family 0 - Opel, Ecotec TwinPort 1.0 (3-cyl) and 1.2, chain, rollers, 10.5:1