1000's don't have a larger auto tunnel

Thats right Neil yet we could still use an auto tunnel
from something else or from scratch thats for sure.

The thing is with the cut, shut and glue or durafix braze
is that we can tilt it a tad to suit bigger manifolding.
Its cheap and easy to implement with the right jig.
Hopefully Simons jig is available to Jmac and I soon ;)

Im now leaning to using durafix cause Ive used it a bit for
repairs and its stronger than my ex-mother in laws burps! :)




The durafix ise a good alternative for lower heat stress.
Its basically alloy brazing with the brushing of the alloy
to create more porosity to make sure the stuff sticks well
These links show its pretty amazing...hts2000 same stuff

http://www.youtube.com/watch?v=N-cv3R4fWZc&feature=related

http://www.youtube.com/watch?v=843jjv58BCA&feature=related

Does it handle vibration well though?

It's hardly going to be that simple or easy an allignment. between the 2 cases. I hope it is.

I honestly don't think the glue and bolt method would ever be able to get it perfect. It needs to be held/locked solid in perfect alignment, and as we all know, tensioning those bolts down can easily pull it a few thou in any direction. When it's a game of thousandths of an inch of runout being the difference between 'works well' and 'destroyed clutch, input shaft bearings, main/input shaft spigot bearing, then related synchros' it just can't be done like that.

The durafix stuff will 'work' and is stronger than some people might suspect, it's still only (mostly) zinc and it's a solder/brazing type job not a weld as such (i.e. the two halves of the job aren't ever melted/welded. On top of that strength issue, if you find that the durafix doesn't work, good luck getting it all off there so you can weld it properly. If any of the durafix is left behind, it has a melting point about half the temperature of the alloy in the bellhousing and gearbox (and similarly that in the tig filler rod you use)

On that front, without a doubt, in my opinion, whichever way one goes - cutting 2 belljhousings and welding an a series bell to a ca 71b case, or doing the crush tube welds and add ons I suggested, or whatever - it'll all be variations on the main theme - which is it'll have to be tig welded on there.

Although I wouldn't choose it from the get go, I think, relatively, that if you cut out the ca starter 'bubble' and placed a curved 'plate' over it and attached it to cover the hole (just so bellhousing didn't have that extra lump to potentially hit the floorpan or trans tunnel) - well the attachment of that small cover plate could certainly be safely done with durafix.

On the durafix stuff - it's actually not bad stuff. Getting closer to 10 years ago (somewhere between 5 and 10) I was being an idiot and defrosting the fridge using a chisel to chip away large chunks of ice around the ice chest section. And I pierced the refrigerant lines in the ice chest. Well I patched it up with durafix (I figured for the $70 odd it cost me for a set of rods, I might as well try it, what did I have to lose, still cheaper than a new fridge) and I then did a diy re-gas using lpg from small bottles (did my own jerry rigged filling device, and the back of the fridge listed the amt of r12 to fill it with, and you can actually do the math and work out the equivalent charge of a butane/propane mix by weight and weigh the bottle before and after till it is spot on.

Anyway, long story short, the fridge is still going strong to this day, (and it was well over 30 years old to begin with when i first punctured the hole in it!)

Point being, yes the durafix has some potential indeed, but I'd not use it on the 'main' join between bell and gearbox casing

That's a much nicer way of putting it Jmac than I was going to. I couldn't bring myself to put it into a 'Don Phrase' so I left it all out. Although the durafix has given me a couple of ideas for the CR conversion.

Don wrote
"It's hardly going to be that simple or easy an allignment. between the 2 cases. I hope it is."

Alignment contraption/toolt Simon made is perfect he made it to be used for the same method of cut, shut the 2 bells.
Not one bell inside other but flush edges, still requires from
6 or more hours of tigging. Still need to heat an attached
A series block on a cooking element for some time before hand
to attain the right temp for welding and later letting it cool overnight all attached together. As far as I remember.

Jmac, Totally forgot think about the tension on the timeserts warping the whole lot!

If I drilled the 71 bell section with larger holes on the outside to expose the smaller bell underneath it could be a
good way to add material in it using durafix or tig it for
starters then progress by doing all the cut edges both
inside and out for extra strength.
Still believe due to the melting point of these brazing rods
that grinding cleaning surfaces with strong wire attachment(s)
where soldering is to be made will make durafix at halve the
temp a better way to avoid any distortion or weakening of the
already soft alloy these bellhousings are cast with.

Any errors using durafix the angle grinder with a number of
attachments will be easy to rectify if needed to clean up.

Out of the 2 methods above the tigging is better if you have
the patience, time and practice yet the durafix should be less
effort and will have the less heat advantages.

David - take it from me, durafix (or the superalloy stuff from muggyweld for guys outside of Aus or NZ) is about being useful for 'certain' types of repairs, and it works very well within that context, but believe me - if you think you'll be able to clear it away with a grinder, or much less a wire brush, you are in for a hell of a tough time. What happens is it will (usually a bit of each every single time) melt and clog the grindng wheel, or the carbide cutter, or it'll melt and keep 're-attaching' to the newly exposed alloy surface you've ground down to. and it'll always be in the way.

The so called 'capillary' action of certain soldering/brazing materials (or whatever the action is called) is quite incredible. For things like soldering electrical wires (for example, and the same applies to durafix) - the way it 'flows' over the workpiece (with just a little bit of practice/experience) - it almost looks like some sort of magic - like the liquid metal cyborg in terminator 2 - it just seems to flow exactly where it needs to go. You'll be chasing contaminants for ages. It's a bit like some cancers - they spread with tentacle like ends all over the place, and the surgeons have to cut out a hell of a lot of healthy tissue just to get it all (or in some cases can't do the surgery as the 'healthy tissue' surrounding the tumour is too vital and they would kill the patient if it was removed from them

It's also definitely no good for tacking something together so it can be welded, as they'd have to remove it all first to begin to weld. Or if they hypothetically then did their own tacking with a tig welder in other locations, and then removed the durafix, well the heat from tigging those spot/tack welds would potentially be enough to cause a small movement of the work piece.

One of the 'features' of this alloy soldering rod stuff (of whatever brand) is that it has some malleability - I think is the term - but basically it has the ability to flex/bend a little without cracking. This makes it fantastic for things like repairs of alloy tube/pipes, and is certainly necessary for it to 'work' on the stuff it is intended to do. But it also means the potential for the work piece to move.

Whichever way you approach it, sadly (and if it weren't the case i can tell you categorically that I'd be using it right now to adapt the gearbox for mine) the durafix, or nuts and bolts just isn't going to 'cut it' for a bellhousing swap. If you had to avoid a bellhousing cut and shut, then the only way forward is a sandwich plate/adapter plate to mount the gearbox to. This is not that hard, though it will mean even more trans tunnel clearance issues, sinc ethe full bell is retained and it is spaced back about 1 inch (and on that note, it's worth going thicker than 12-13mm (or half an inch) with an adapter plate so it won't flex). That's going to add a few kg too, (not that that would phase me).

Then you need to spin up a hub on a lathe, so it bolts to the back of the crank (or sits there) and sits perfectly centred, the same thickness as the adapter plate, and with a lip on the other side, so the flywheel sits on the back of it, and remains fully centred. Then you get custom longer flywheel bolts (the strongest you can get) and locktite and tension them, and run lockwires or locktabs as well. And you'd better make sure there isn't much clearance between bolt shanks and the holes in the flywheel or it will tear itself loose. You could certainly dowel it. And then a custom spigot bush - maybe due to the trans sitting back 1 inch, you could run a 'stepped' spigot bush that fits into the crank tail, but then has a larger i.d. from the tail of the crank rearward.

But what I'm getting at here is that that is - realistically there's probably not any 'lucky break' to be had going with an adapter plate either - either way you are in for some time with lathes/mills/welders.

It's just what it takes I guess. Don't get me wrong, I'm far from a millionaire, and just putting aside enough dough to get the boxes, and even a fairly modest lathe/mill/tig welder can take some doing. Until then it's basically a case of trying to grab all the overtime I can, and 'waiting it out' so to speak. If there were simpler ways, believe me, you'd be seeing them in the real world, as there's plenty of very cluey people into early datsuns, and they'd certainly have weighed it up and tried it if it had even a little bit of promise to it.

I think Ill stick with the cut and shut as Simon has done it and its been spinning well in his setup. However I would like to avoid 4-6 hours of tigging if possible but if the durafix and Loctite like Devcon products are not enough then there is not much else left to but the very hard to align adaptor plate. Which will cause some fitment issues.
Ah if only nissan made them all removable bellH 5 speeds!

ah swap to l series, then no more dramas