Strengthening of Rear end components in *Z1*/MA61??

[Forcefed6]

Well I had a pretty disapointing venture back to Willowbank raceway on Saturday night... It seems that I have now found more weak links in the rear of my Z10 Soarer.

I have previously broken the output splines in the diff (both at once), and was full well intending (if that is the word I am looking for) on seeing some more broken this time round.... but no... This time it snapped the spline of the outer stub axle (MS123).

I know 450-500 bhp is alot to ask from these little shafts, let alone the shock from a transbrake, but are there any stronger aftermarket options available out there.

I see a few cars in the build, that could by means themselves find the limits of the tine rear end these cars have. One car that comes to mind is whatthe?'s MA61...

Will billet parts be stronger?

I will get some photos of the broken bits tomorrow, which might explain more

Thanks in advance

Jamie

[CrUZida]

Sounds like it might be time for a complete MA70 rear end swap.

[Forcefed6]

Yeah, but I don't really want to increase the track at all.

After talking with some people, I may have a look, and see if I can re-engineer the whole rear end to run 30 splines instead of the standard 27. This may involve making new stubs and a full spool, but I don't think it will ever break again.

Anyones thoughts on the above?

Anyway, these are the first set of diff axles that I broke a while back...


And the most recent breakage of the MS123 stub axle.




Cheers
Jamie

[wilbo666]

Hmm..

What's the OD of the bearings used in ma70, jzz30 etc in the rear...

Possible to look at using those rear hubs?

And then getting billets that go into the diff? Changing the spline sounds quite annoying...

Cheers
Wilbo

[Forcefed6]

Hmm..

What's the OD of the bearings used in ma70, jzz30 etc in the rear...

Possible to look at using those rear hubs?

And then getting billets that go into the diff? Changing the spline sounds quite annoying...

Cheers
Wilbo

Which bearings?

If someone had some parts they would let go of for a bit, so I could work out if they could be made to work or not, I would look at it.

Changing the spline might sound annoying, but not as annoying as having it break something everytime it goes back to the track. I was intending to convert to a GTR diff if I ever broke the diff shaft again, but I never really expected to break the outers like this, so that kinda throws a spanner in the works.

We are also toying with the idea of maybe converting to a live axle rear with a hilux diff and triangulated 4 link setup and coil-overs.

Surely their has been someone that has got these this to run a good time in Japan or elsewhere.

[wilbo666]

I think ma70 etc uses a large single bearing? And the hub pulls it tight?

I was having a quick look on the EPC, I've never actually had one apart tho...

The more I think about it tho, the more I think billets would fix the issue.

I recall the stock outer hubs at least being very soft...

Cheers
Wilbo

[Forcefed6]

Well pending a chat with Linden tomorrow, I may have a solution for the diff, and some replacement MS123 stubs. But I think getting some billets made would be a good option.

I know there could be a market for copies of an MS123 stub axle, but I'm not sure most people would really like to spend that much on a set of hubs. I know there getting harder to get and all, but there not gonna be cheap.

I should have a price on the material to make up a set tomorrow, and this will help me decide if I proceed to have a set made or not. I'm not made of money, but I can only imagine what a 400mm piece of 165mm billet Cro-Moly 4340 is gonna cost, then the machining and splining.

[Norbie]

If this is a drag weapon there is a lot of merit in a solid axle conversion. Hilux diffs are cheap and plentiful...

[driftedmz20]

Time for chrome alloy custom jobs.....prob cost you the best part of a grand but will be worth it as they will full rotate 3 times before they snap

had to do this on a R30 as was always snapping them with rb20

just a thought but i guess depends on where you want too go

[VA61DETT]

Hi,

That’s a real worry about the axels breaking!!
I just finished my commodore to ma61 diff conversion,
after snapping the diff splines in the same way.
Was just thinking ‘the next weakest point is the axels’.
Will see how it all holds up, but if they break I may look
at getting the swing arms from a commodore IRS, carve out the bearing holders
and attach to the Toyota arms, or just make my own new ones based on the Toyota geometry.

Too hard basket, mmh probably, I do like the idea of the MA70 rear end, better handling and wheel offset etc…
But if just going to the drags, can't go past a good’ol (shortened) 9inch. grin

BTW How many torques are you throwing at it?