Right its been discussed heaps but would like my own
thread for an A series box conversion that is strictly
using 71 series box using some kind of adapter plate.
The plate so far that Im thinking of is something like this

oops forgot the pic, thanks Big V
Im also looking for the 1983 bellhousing of the fairlady turbo 280zx
that uses the old non WC T5 for my L16 conversion.

Here is the Adapter in mind must first be bolted onto the A series
yes it will need the input shaft machined to suit a series spigot
but .........
HOW FRIGGIN COOL IS THIS!!!!!

We are waiting for the gearbox GURU 2 start a group buy! U know who you R!

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  a series adapter.jpg (137.48 KB)

If no box gurus are interested Im going to ask a Kiwi who makes adaptors like the one above for a quote.

looks too easy..

That one looks great. An A series one would have to have provision for bolting the starter to. The tunnel clearance will be a problem when doing it this way and the clutch plate and clutch activation would still have to be worked out.

Simple way of doing multiples tho.

Sample image just for reference definitely needs starter hole as for tunnel mods/bashing :) its a prerequisite with big box. Space/time could be saved if we can possibly use something like a Gm hydraulic release bearing, which are quite affordable these days from different place like summit and this place as an example, what do you guys think?
http://www.ramclutches.com/zen-cart/i ... ?main_page=index&cPath=63

http://www.ramclutches.com/zen-cart/i ... 25f638a00f8458c6797bf1c67

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  gm unit.jpg (65.95 KB)

Better and cheaper in 8mm steel plate to replace the stock backing plate?

Need some views got Master gbox adapter dude's response

Quote:

I guess I will need Simons or Donalds input.

would it be best to send him the backing plates or the bellhousings?

Im thinking the A15 flywheel and clutch will to use stock starter?

I`d guess backing plates should be fine for a template. The length of the gearbox input shaft should be what determinds the thickness of the plate. Remember threads will be cut in the outer holes. Thread engagement probably should be 1.5 times bolt diameter. The bellhousing bolts are 8mm, Threads for the starter bolts are 10mm or 12mm. I would think 15mm should give enough bolt engagement.

If they are going to be milled out, ally will be cheaper to make.

I wouldn`t be ordering anything until you have at least made sure you have all things covered in full.
Things like, Hydraulic clutch activation(master and slave), where and how the input shaft will spigot, Clutch and pressure plates and if it will fit the tunnel without major surgery.
Tailshafts and gearbox crossmember have to get made aswell, but they can be sorted later.

With the spigot bush location, it can be also be put in the flywheel insead of the crank. So if the adator plate makes the input shaft not reach the crank, its not the end of the world. This may also mean that the 71b input shaft may not have to be machined to fit the original spigot bush.
So either the shaft will have to be modified or a new bush made or maybe both.
The other thing is ensuring the shaft spline is in the right place for the clutch plate once its all bolted together.

The adaptor plate is probably the easy bit.

At Holinger, we also have a CMM. The measuring is the easy part. To measure the co-ordinates of just the bell housing would take half a day. It can also be done with a mill. It comes down to more than just a few things. The dowell positions of the block govern the position of the gearbox as well as the starter motor spigot. If dowell positions arent a perfect match between the new gearbox and the block then there must be sufficient clearance that they will not interfere with one another or the adaptor plate will need to be thick enough to compensate for the two sets of dowells sitting almost on top of each other. As the A series dowells are at the wide as point it makes it a bit difficult as they do interfere with L series bell housings. This can be overcome. But not with offset (eccentric) dowell pins. You need to make the adaptor thick enough to clear both pairs of dowell which brings your adaptor plate to a minimum thickness of 22mm.

So the trick is to find a bell pattern that the dowell do not interfere. Then you can achieve a 10mm plate.

I would find out how much it would cost to get your plates and housings CMM'd before starting as this would have to be calculated into the price of the adaptor.

There are more things but I don't have the time right now but good luck. If it can be done cheap I'm on board for sure, in fact I'll even see if I can con my boss into doing the CMM work for free.

Thanks for the input shaft so far :)

In all honesty I prefer you Don to be in charge of the project rather
than someone in NZ which is where this fella Ben is and makes adaptors for
suzuki vehicles but Ill be happy if you dont have the time to work with
him if you cant convince your boss for the nitty gritty.
If you can just discuss what we need once we come to some ratification then
in can remain in concept only until we get the numbers of interested in such
a venture but seen how peeps are quickly running out of 5 speed choices for
a boosted A series or a 5 speed in general, it must be considered.

Some points to make things easier accessible for everyone as we will need
numbers to make it possible to cover costs and peoples time.

1. Only set it up for the CA series bellhousings (more common)

2. A piece of CA bell has to be taken out to allow starter (1st picture below)

3. Thickness will be an issue but 10mm would be enough for the circular
torque/force all in one direction. Maybe a step is needed but could also
factor as Simon has mentioned whether the length of the input shaft can
be factored into the flywheel or other means.

4. Hydraulic release bearing or conventional Hydraulic CA setup?

5. Make use of A15,14 or a12 flywheel diameter to avoild starter issues.

6. Even if it cost more than a Dellows bellhousing for the T50 peeps must
remember the 71 series has better first gear for lightweight powerful cars
like datsuns and a stronger box that can take almost anything dished at it.

7. Group buy of required numbers with money upfront to make it worthwhile.

The last pic ask Don specifically if I wrong to think that we could get away
with 4 well placed bolt locations to secure the plate to the CA bellhousing?
I put 5 possible locations in green outline maybe 5 is better anyway.

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  A series on top of Ca bellhousing 2.jpg (92.49 KB)