General Requirements for L67 conversion into factory 5 speed manual (T5/getrag) commodore

• Mirror balance flywheel to flexplate (balance pressure plate to FW for added security)
• Get the crankshaft drilled for flywheel dowels to fit flywheel
• If running the factory loom then several wires must be extended including:
• Fuel injectors
• Crank angle sensor
• Temperature sensor
• High flow fuel pump (walbro 255LPH EFP-057/GSS-342)
• PCM/memcal must be recalibrated.
• These following steps regarding wiring only apply if your undertaking a complete conversion (meaning Ecotec/Buick V6 and automatic transmission swapped with an L67 and manual transmission)
  - bridge neutral/park safety switch permanently for the car to start
  - wire up the manual speed sensor to the dash (3 wires)
  - wire the manual reverse switch to the reverse lights (2 wires)
  
  

General Requirements for L67 conversion into factory 4 speed auto commodore

• If running the factory loom then several wires must be extended including:
• Fuel injectors
• Crank angle sensor
• Temperature sensor
• High flow fuel pump (walbro 255LPH EFP-057/GSS-342)
• PCM/memcal must be recalibrated
• Make sure you retain the L67 flexplate when purchasing the motor as the ecotec and L67 have dissimilar rotational harmonies
• These following steps regarding wiring only apply if your undertaking a complete conversion (meaning Ecotec/Buick V6 and automatic transmission swapped with an L67 and manual transmission)
  - bridge neutral/park safety switch permanently for the car to start
  - wire up the manual speed sensor to the dash (3 wires)
  - wire the manual reverse switch to the reverse lights (2 wires)
  
  

General Requirements to turn an L36 (ecotec) into an L67 (top swap)

• L67 cylinder heads
• L67 lower inlet manifold
• L67 blower and intake
• L67 tensioners and pulleys
• L67 alloy coolant pipe
• L67 harmonic balancer (mirror-balanced to suit ecotec bottom end)
• L67 vacuum hoses or can be purchased from auto parts stores in different lengths/diameters
• L67 fuel rails
• L67 36lb injectors
• L67 Alternator
• If running the factory loom then several wires must be extended including:
• Fuel injectors
• Crank angle sensor
• Temperature sensor
• High flow fuel pump (walbro 255LPH EFP-057/GSS-342)
• PCM/memcal must be recalibrated

 
Due to the asking price and rarity of VS L67 looms you'd be best to use a VS ecotec engine harness and PCM. To do this you need to have an L67 tune burnt to your memcal and the wiring harness will need to be extended approx. 150mm on each plug on the driver’s side (canister purge solenoid, 3 injectors, earth, oil pressure sensor and knock sensor). By using the ecotec harness you also bypass the dual stage fuel pressure reg and the boost control solenoid as the loom will not contain the necessary plugs (a good thing in my opinion). The only wiring to be modified on the driver’s side is the plugs to the coolant temp sender and sensor which need to be extended to the rear of the motor to suit an L67 or you can unwrap some of the harness. The alternative to this is to source a factory VS L67 engine harness and PCM which are becoming rare and pricey. It’ll probably be easiest to buy another stock VS ecotec loom so this way you can modify it up front before you're ready to swap motors and you can fit it to your l67 whilst extending etc. to get all the lengths correct.

Just a note on terminology, the coolant temp 'sender' is the small brass fitting which works the cluster temp gauge, whereas the larger coolant temp 'sensor' provides operating temp info to the PCM. A coolant temp sender and sensor is used in a VS, whereas later models run just run sensor and the cluster gauge is therefore signaled via the PCM.

Regarding the temp sender, the thread is 1/8npt. It is a tapered pipe thread, not parallel, and therefore gets tighter the further the sender is inserted. If you look at the back of your l67 on the passenger side, locate the coolant temp sensor in the back on the lower inlet manifold under the thermostat housing. You want to add your VS coolant temp sender on the front side of this, between the temp sensor and the back of the passenger side cylinder head (this is only the case if you’ve purchased a post-VS L67). Alternatively, picking up one of the adapters shown in the picture on the right is also ideal.

On the left image you'll see a post-VS L67 with no temp sender adapter and on the right you'll see an L67 fitted with a temp sender adapter for VN-VS applications.

VS ecotec throttle and cruise cables can be used, but are different to factory VS l67 items. In particular the throttle cable is much longer and runs under the driver’s side front guard, across the top of the top radiator support and then round to the throttle body. This is to give a much smoother curve in the cable so the bends are not as tight as they are when using the ecotec cable which runs across the firewall.

The VS air-conditioning pump (compressor) and passenger’s side engine mount bracket are different from later models. (The VS engine mount bracket also supports the VS compressor so reuse the VS compressor and the VS passengers’ side engine mount bracket).

Use the VS drivers’ side exhaust manifold.

If installing an L67 with the factory 4L60e auto that came with it into earlier commodores like the VN-VR, a portion of the box will need to be shaved in order for it to sit comfortably inside the transmission tunnel. This will be a case of trial and error until the right amount has been removed.

In most cases Mace Engineering will be able to provide a memcal or PCM/ECU recalibration for you to be able to run the L67 without any worries. Please refer to the hyperlink below and submit to us a report thoroughly listing all specifications of your vehicle including any current modifications prior to making a purchase.

VS commodore running the L67 with factory VS ECU
(select set-up from drop down menu)