Nismodore Frequently Asked Questions


I get asked a lot of questions about how I did things with the Nismodore. Below are the most common ones. Please read through them before contacting me.

How Long did the conversion take?

From ripping the old motor out to taking it for its first drive, probably about 1 month. Bear in mind that I had to make my own wiring loom. That took many nights work. The actual transplanting of the engines can be done in one day easy. It is all the fiddely work like hooking the electrics up, plumbing the cooling and oil lines and making an exhaust. If your engine came with a loom, that's half the work done.

Do you have a diagram of what to wire up?

No, other than the diagrams listed on the main Nismodore pages I do not have any diagrams. I have the diagram which shows what to connect from the commodore side to the nissan ecu, but I don't actually have the wire colours or numbers to show this. I often get asked what to connect up under the glove box to the black and blue plugs, unfortunately I never documented what I did here.

If you have done a recent conversion, and would like to share your informant ion to help others out, please contact me so we can arrange for a diagram to be made to display on (credit will be given)

Can I wire it myself or do I need to take it to an Auto electrician?

That depends on wether you are comfortable with wiring it yourself. If you can follow diagrams and know the electrical differences between a '+' and a '-' symbol you can probably attempt it. If you can't figure out why your indicator isn't blinking, I suggest you take it to a professional.

What engine mounts did you use?

I used the standard Commodore engine mounts. As in I removed both completely from the old engine and mounted them to the RB25 block. This ensures the engine once located on the cross member mounts is at the correct height and set back correctly.

How did you mount the starter motor?

I used the standard Commodore starter motor as this saved me wiring up the cranking circuit. The standard motor I had was bigger than the one that came on the RB25, and I thought - Bigger must be gruntier!

How did you mount the power steering?

For the power steering I used the standard Holden power steering pump and brackets. This saved making new power steering hoses and ensured compatibility between pump and rack. The only thing I needed to do was cut a small section out of the cam cover for clearance of the Holden bracket.

How did you mount the air con pump?

My Commodore didn't have air con so that wasn't an issue. However if yours does and you want to retain it, I suggest using the standard Holden brackets and pump.

What gearbox did you use?

I used a RB20DET gold top gearbox for my conversion. This is the box you'll find behind any R32 RB20DET skyline. This box is physically the same dimensions as the RB20 or RB30 box for the commodores. The R33 RB25DET gearbox is quite a bit larger and from what I have heard will not be cleared by the transmission tunnel.

This also means I could use the standard Holden gearbox cross member.

How did you connect your speedo up?

The Nissans have an electronic speedo where as the Commodores have a cable driven unit. I just pulled the electronic sensor drive out of the gearbox and fitted the Commodores cable. The problem with doing that is that your speedo calibration will be out depending on your final drive ratio etc. This can be overcome by either finding the correct cable drive gears (not much to choose from) or redesigning your dash to suit.

Perhaps someone local in Wellington let me sniff around their R33 skyline to research making a conversion kit?

How did you connect the clutch up?

I mounted a Holden VL Commodore slave cylinder on the Nissan gearbox. This ensures compatiblity between the master and slave cylinder.

Did you fabricate your own driveshaft?

As I used the RB20DET Gold Top gearbox the standard VL drive shaft slides into the back of the Nissan gearbox. This saves a lot of hassle

How do I connect the exhaust?

Your best bet is to get the dump pipe from an R32 skyline. This follows the contour of the Commodores floor pan nicely at which point you can cut and make the rest of the exhaust up as you see fit.

Did you need to have it Certified?

In New Zealand, when you increase the power of a vehicle by 20% (I might be wrong on that figure) by way of engine transplant, you will need to get your vehicle certified. Any certifier who knows their stuff will realise that once you that this RB25 commodore those standard desert plate front discs and drums on the rear wont cut the mustard and you will need to upgrade your brakes. The Holden VL V8 brakes will suffice, however bigger is always better!

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