Just to chuck it out there the Z series gearbox has the same pattern as the L series ( I think ) but the engine leans a different way and the rotation of the stud pattern on the gearbox is changed.

May be the solution for the dowel alignment and also give a common low demand bell housing ( plenty of warn out Navara's )that swaps to the correct size gearbox ( i have swapped the z front on to an L box )

I might even have a backing plate to check might wander out the shed later see if I can see one

Only issue I could see is that the Z leans to the passenger side and the reason I didnt consider the Z or L is that its around 37cm wide while the CA is 34cm and the A series around 32.5cm. The L has more chance of causing headaches due to its width.

What I like about the CA boxes is that the ratios are good while some Navarra boxes
are 3.85 or even worse. The CA donk is also an upgrade option later with stock input shaft put back in then all the work of fitting the box is complimentary :)

Also when the day comes that someone wants sequential shift action there is a kit from Japan that converts the 71C to sequential.

For $1500 US&A I'd rather put my money elsewhere. Those seq mechanisms have been around for a while and have so little demand they're made to order. Tickford played with a T5 version 12 years ago or more and they cannot be made reliable. For daily road use at least. It's a novelty That's about it. Pay another $12K and buy a real one.

It is exxy for road fun but for 12k full Busa running gear is better datsun value

Can anyone seen on the photo album under engine if there are any engine rear face pics and bolt face pics to let Ben work out the dowell positions? Otherwise will have to take pics of those things this weekend sometime under the house.

David I have a couple of a15 engines here that can be utilised. I also have a ca20 spec 71b box so pics can be taken of all relevant meeting faces. With a few bits of wood etc, we could also 'dummy' mount the motor and box together and centre it (within a few mm or so) and take some pics to show the overlap etc.

I've also got a bunch of paper/thick glossy cardboard that could be used to trace the various items (or with judicious use of a ball peen hammer, hit around the corners which will highlight the exact sizes, and could be used to start the adapter plate measuring/design.

PMd John

In order to press on with this project I will need a couple of things. A bare A12 block with main caps and backing plate, as well as a CA18 RWD block and if possible a backing plate. My boss has agreed to take a look at it and do some measuring when time is available.

Engine blocks are the best to use as they can be set on the CMM much easier and you will know exactly where the thing is sitting. Also, the cast iron is much stronger, heavier and much less likely to distort Whereas the alloy can distort over time. So the most acurate way is to use the block to make the adaptor plate. As for the bacing plates, I have an idea on how to work out if it will work by spigoting the 2 together and drawing a few lines first. If it is obvious that it won't work then there is no point wasting valuable time.

Backing plates for A series and Ca. Who's willing to donate?

I can lend an a series gearbox if that helps? Probably not from what you've just said.

Edit: As it happens I have a W5x gearbox sitting next to the a series 56 4 speed hoping they'll get the picture and sort it out for me

I have an A-series backing plate and bare blocks if required..