Hilux 4x4

 

 

 

Engine differences 2.7 Pre-Facelift & Facelift Toyota Hilux models - Willem Grimsell

The attached pictures shows the two different head and intake runner configurations for the pre-facelift (8 port) and the facelift (4 port) heads on the 2.7 Hiluxes, pre-facelift being from about 99-2002 and the facelift 2003-2005. From my research it looks like the 8 port head provides more torque low down and responds better to a gasflow and mild cams as well as having better fuel consumption. I am currently contemplating fitting an 8 port head to my 2004 model. Some of the other differences are the airflow meters, the pre-facelift models uses a MAF with the facelift models using a MAP sensor, valve timing and exhaust manifolds

4 Port Inlet Manifold of the Facelift Hilux (2003-2005)

Hilux inlet manifold

8 Port Inlet Manifold of the Facelift Hilux (1998-2002)

Hilux inlet manifold

The changes were done to comply with the California emissions control standards as can be seen from the extract below from the attached file, click here

NEW FEATURES - 2RZ-FE AND 3RZ-FE ENGINE
1. Description

  • The generator has been changed from 70 A to 80 A for both engines.
  • On the California specification model, both engines comply with the LEV (Low Emission Vehicle) requirements.
  • The EGR (Exhaust Gas Recirculation) system has been discontinued for the 2RZ-FE engine.

2. LEV Compliance
General - To comply with the LEV requirements, the following changes have been made:

  • The shape of the intake port of the cylinder head has been changed.
  • Valve timing has been changed.
  • Along with the change in the shape of the intake port of the cylinder head, the intake manifold has been changed.
  • A compact, 1-coil type IAC valve has been adopted.
  • An exhaust manifold made of stainless steel has been adopted.
  • WU-TWC (Warm Up Three-Way Catalytic Converter) is used.
  • Compact, fine-atomization, 12-hole type fuel injectors have been adopted.
  • The DIS (Direct Ignition System) that provides one ignition coil for every cylinder has been adopted.
  • Air-fuel ratio sensor is used.

Cylinder Head - A Siamese port configuration has been adopted for the intake port of the cylinder head.

UPDATE - 23 Sept 2008
I picked up another difference between the 8 port/4 port pre-facelift/Faclift hiluxes while going through the part no's. I thought it was only the cam timing that was different but it looks like there are two different cams being used in the two models. The exhaust cam on all the 3RZ-FE enigines are the same Toyota part no 13502-75010, the cam sprocket is also the same Toyota part no 13523-75010. On the intake cams there are two part no's 13501-75030 and 13501-75040, the first one seems to have been used on the 8 port/pre-facelift models and the latter on the 4-port/Facelift models. I will be visiting my local Toyota dealer to try and confirm this and if this is the case I will be getting the 8 port intake cam for mine to try out. This could be one of the major reasons for the difference in fuel consumption.

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