Turbo Conversion Information

If you're after more power for your R31 Skyline and naturally aspirated just isn't cutting it, the decision to go turbo is a simple one.  You have 2 main choices if you want to go turbo:

1: Keep your old engine and turbocharge it
2: Get a manufactured turbo engine

Obviously the first option is going to be cheaper (as long as you're prepared to do the labour yourself) but the second option is usually safer.  Properly done, the conversion is even better than a manufactured turbo engine.  To do it yourself you will need the following:

• Exhaust manifold from turbo engine (get one from a wrecked VL turbo or have one made up)

• Turbo itself (Garrett T03 was a stock unit, accept this as a minimum)

• Turbo injectors (approx $98 from your local spare parts store)

• VL Turbo ECU - you NEED this to run the turbo injectors, they use a different pulsewidth to the NA engine injectors

• Intake pipes - from turbo to intake manifold, stories circulate how the NA plastic ones tend to explode under boost, metal ones are needed

• Dump pipe from turbo to catalytic converter (you'll probably want a bigger exhaust system as well)

• Exhaust manifold gasket and turbo to dump pipe gaskets

• Oil and water lines to run to turbo, these are essential to your new turbo to prevent it exploding!

• Knock sensor: detonation can be a problem if there is too much boost or not enough octane in the fuel.  This wires up to the VL turbo engine computer

(OPTIONAL)
- Blow off valve
- Intercooler
- Turbo engine oil pump (it was bigger on the turbo motor)

If you're building an RB30ET and use a VL series 1 engine block, you need to put a T-piece in the oil pressure sender hole in the block and use one of those for the turbo oil feed line.

Armed with that gear, the right tools and decent mechanical skills you're away.  Keep in mind the turbo engine had a compression ratio of 7.8:1 (from 9.0:1 of the NA engine) so be careful, higher compression ratio means you can't run as high boost without detonation.  If you leave the compression at 9.0:1 DON'T run over 7psi of boost without an intercooler or detonation will result.  The turbo engine has a different camshaft for 5° more duration and 5° more lift (gives more exhaust to the turbo and lets more intake in), the NA one has better midrange torque and less lag.

You will need to swap the timing belts and spark plugs as well, a small but worthwhile effort.

   Engine Swap

For a complete VL Turbo (RB30ET) engine swap you will need the following:

• RB30ET complete engine

• Original RB30E engine for parts leeching (mainly the rocker cover - who wants Holden on a Nissan engine!)

• RB30ET ECU (without this the entire crusade is useless!)

The swap is a fairly simple one, the engines being almost identical.  You will have to run the knock sensor wire back to the ECU as well as change the pin for the fuel pump (pin 22).  The VLs used 2 fuel pumps both outside the tank; one for low pumping, another for high volume pumping.  The R31 has 1 fuel pump inside the tank that can vary it's speed.  There are numerous explanations on how to wire up the fuel pump, some being quite complicated.  The mechanic who set mine up however 'simply swapped the pin' on the VL turbo ECU and it's worked perfectly.  I am in the process of getting more details and a diagram.

Note that after the engine upgrade is done, you will need bigger brakes and an engineers certificate in order to change your registration to show correct details.  Different states have different requirements however so check first.  Note also insurance will probably be unavailable through most companies due to a modified vehicle.  (Just Car Insurance will insure almost anyone driving anything, but be prepared to pay for it!)