how to convert your 1HZ to 1HDT

HomeBloghow to convert your 1HZ to 1HDT
how to convert your 1HZ to 1HDT
Posted on 8 November 2017

Toyota  1HZ are indirect injection –

Which means they have a Precombustion chamber is  in the cylinder head – the injector injects directly into the preco chamber ( this is why it is common for 1HZ cylinder heads to be cracked )

Toyota 1HDT are Direct Injection

Which means the injector squirt directly in the bowl if the piston shown below and the explosion occurs in the piston bowl – preventing the cylinder head from getting so hot and reducies the cyl head from cracking

Unfortunately the 1hdt and the 1hz heads are not interchangeable without changing the complete fuel system and the pistons and con rods the only things you can use on both engines are the block and the crankshaft
  • What you can do is use 1hdt conrods as they are stronger and use the 1hzt piston to get a better stronger 1hz turbo
  • In the direct injection 1hdt the combustion happens in the piston
    Noordeman 1hz 1hdt
  • In the indirect injection 1hz the combustion happens in the combustion chamber in the cylinder head
  • The 1hdt injectors have protruding nozzles and 1hz injectors  are flat  they are totally different also as pictured     

    1HDT Injectors Noordeman

Noordeman 1HZ injectors