Sirpent "Z"

[garvice]

Gees, you don't piss around. Suddenly all my work feels very agricultural.

[peter mc]

hahaha lots of hitec farmers in Vic 

[Sirpent]

Gees, you don't piss around. Suddenly all my work feels very agricultural.

 

Yup thats why the render is in C.A.T. color LOL

 

hahaha lots of hitec farmers in Vic 

 

So Pete, are you going to find enough time between jobs to plough the wheat field for the upcoming season?

[peter mc]

yer been work en on a twin turbo tractor so we can plough faster

[Sirpent]

Question,

 

Has anyone with the Arizona rear moustache bar set up which puts the sway bar in a counter position found this a more effective set up?

 

Fine tuning done, and machinest confirmed no issues with file or program, will now produce a cut mock-up for fitting and testing purposes

 

Cheers

 

John

 

[NZeder]

John,

 

I believe the mounting of the sway bar in that way is 2 fold.

 

1. Early shell don't have the factory sway bar mounts on the rear subframe just forward of the lower control arms.

2. When a S30z is lowered the factory mounts cause issues so behind the diff is a better option.

 

There is a sway bar kit from the US that comes with new hanger arms so mount from the rear also. This is the one Beta Motorsports resells (I forget the actual bar supplier)

[Sirpent]

Thanks Mike

 

Reason I asked is because it would be nice to think about this option now while Im working on this set up rather than later. and may assist in cleaning up the frontal area at the diff.

 

Cheers

 

John

[benny]

Quick observation john,

 

 

Aren't the main points that hold the mustache bar a tapered bolt?? Wouldn't it be better to have your new setup follow the taper for a snugger fit??

 

 

Ben

[Six_Shooter]

Just a few things.

 

Spacers between cranks and flywheels not only have been used by people adapting trannies to engines, but by the OEM as well. Nissan used spacers between the flexplates and the cranks on the auto L-series, I have seen some Ford and GM applications that also have had spacers between. Done right, it's a good solution to an indirect connection. Sorry just some some old MOPAR jabbing there, when they used to have "Direct Connection" as part of their advertising.

 

I love the T56 follow through. I plan to use a T56 behind my engine when I swap it in, also an engine that was never bolted to a T56.

 

An idea I'm considering for my adapting duties: http://www.thirdgen.org/techboard/fabrication/615761-homemade-bellhousing.html

 

That looks like a pretty wicked diff mount, can't wait to see it after the aluminium shavings are cleared away.

[Sirpent]

Quick observation john,

Aren't the main points that hold the mustache bar a tapered bolt?? Wouldn't it be better to have your new setup follow the taper for a snugger fit??

 

Ben

 

Hi Ben,

 

Well done good observation, obviously the wire frame gave it away.

 

Just to explain, the dia on those hanger bolts starts at 17.5mm and yes they taper, so as to cut down costs and complexity of producing this unit, the production process will be a 3 step one, let me explain.

 

First the plate will be CNC'd so as to create the web reliefs only not the webbing cut through.

 

Then the plate based on a zero point start point will be water jet cut, the reason for this is simply because CNC'ing the whole lot would mean that a lot of material would end up on the floor, this was I will have a number of sizable pieces left as direct cut aways to uses for other needs I have planned.

 

The mounting wholes or shafts will not be done by either the CNC nor the water jet, however the water jet will cut 6mm pilot holes, later these shafts will be individually machined to requirements.

 

This is why the hanger bolts in the wire frame show a uniform 17.5 mm cavity which was just to gauge overall material penetration at the maximum diameter, prior to cutting these will all be reduced to 6mm pilots only.

 

Just a few things.

 

Spacers between cranks and flywheels not only have been used by people adapting trannies to engines, but by the OEM as well. Nissan used spacers between the flexplates and the cranks on the auto L-series, I have seen some Ford and GM applications that also have had spacers between. Done right, it's a good solution to an indirect connection. Sorry just some some old MOPAR jabbing there, when they used to have "Direct Connection" as part of their advertising.

 

I love the T56 follow through. I plan to use a T56 behind my engine when I swap it in, also an engine that was never bolted to a T56.

 

An idea I'm considering for my adapting duties: http://www.thirdgen.org/techboard/fabrication/615761-homemade-bellhousing.html

 

That looks like a pretty wicked diff mount, can't wait to see it after the aluminium shavings are cleared away.

 

Much appreciated, the link was very interesting but I wont be going to the extreme of fabricating a bellhousing LOL

 

I'm trying to con my brother in-law to take the the parts required to his work, (He works for an aerospace mob I cant mention the name of) and get the required faces laser scanned and digitised into dxf files, then just import them into the CAD program and see if I can come up with an adaptor, failing that, has anyone got a HR photocopier LOL, don't laugh it can actually be done.

 

Cheers

 

John

[benny]

I thought you wouldn't of missed it!! great idea on the water-jetting... material is not cheap!! I assume your getting a mock out of MDF first??

[Six_Shooter]

I thought you wouldn't of missed it!! great idea on the water-jetting... material is not cheap!! I assume your getting a mock out of MDF first??

 

I think I'll do that next time I need to mock up some brackets.

[Sirpent]

I thought you wouldn't of missed it!! great idea on the water-jetting... material is not cheap!! I assume your getting a mock out of MDF first??

 

Yep that's the next step, but in plywood for strength, then hang it all off the car and see how the diff sits followed by some bracket design work and finalising the rear diff mount point of the cradle before cutting.

[FLEXZED]

hey mate

 

That some awesome work, will be following this closely

 

Loui

[Sirpent]

Thanks Loui

 

As I mentioned before, I will have some material left from the plate, and I had plans to use it rather than it ending up as expensive waste on the shop floor, so I sat down and did some measurements and have decided that I will cut 2 rose joint mounted and adjustable lower front control arms out of the 2 remaining pieces and came up with this universal design using the original geomentry of the OEM arms.

 

Each arm has a mount point either side for an adjustable tension rod meaning they can be fitted either right hand or left hand side therefore making them universal.

 

See how they go, nothing ventured nothing lost.

 

Cheers

 

John

 

[peter mc]

hi sirpent

mate make sure that rear mount for the diff is a ford mount as the rear plate on the diff is weak and prone to braking with after market bushes i have changed 2 this week  ,,,

[Sirpent]

Pete

 

Will do after I bench the diff this weekend for alignment and get the correct geometry, what I have in the carrier at the moment is just speculative and will modify once Ive measured it all up.

 

Cheers

[benny]

looking good... cant wait to see all this shiny stuff cut out!!

[Sirpent]

Today's effort

 

So, in order to determine the rear mounting position for the diff on the cradle, I had to first determine where in space the original Z diff sat so as to determine first and foremost the position of the axles within a horizontal and vertical vector.

 

Rather than trying to hang the diff in empty space and attempting to eyeball its position, I decided to bench measure both diffs critical dimensions and central yoke and axle positions.

 

Because I know exactly where in space the old diff mounts on the old moustache bar, I could use these bolt point to determine the position of the diff in space aligned to the same fixed points on the new cradle, have I lost you guys yet?

 

So, here is the short abridged conclusion.

 

 

                                                        Z Diff                  M86

Width                                              250mm              240mm

Height                                            245mm              260mm

Yoke offset to axle flanges              50mm                45mm

 

What this all means is that the M86 sits within the same space of air on the original diff axis points with very small differences (millimeters)

 

Obviously the nose is shorter however that's the reason for the cradle.

 

The only stumbling point is that the M86 diff hat mount sits outside the cradle face, this became a concern as the spare wheel well and then fuel tank may have impeded furnishing a bolt on support which would connect it to the cradle on the rearward side.

 

However after doing some more measurements there is enough room to drive a Kenworth through.

 

Took a total of 5 hours to create a level surface, postion the diffs one at a time square and leveled and then jot down 4 pages of measurements but the results were great, I will now transfer them to CAD so I can align the carrier mount point and the forward supports positions into the design.

 

Cheers

 

John

 

Pics show diffs side by side after measurements where taken, I have lined up the axle heights and alignments by eye to give some idea of the proportions and positioning.

 

 

 

 

[luvemfast]

Jeebus John.

Once again, making us all look bad.

You spent 5 hours measuring all that and I can't find the time to get into the garage at the moment.

[Sirpent]

Yeah I know Simon,

 

Seems a bit of time overkill, but important in the scheme of things for me anyhow, objective is to get this diff sitting in the same geometry as the R180 as far as yoke alignment first and foremost and axle output symmetry.

 

After some plotting last night, using the Yoke center lines as the absolute, this is how it pans out, the M86 axle centers sit 5mm higher on the centre line, at the rear you will notice the relative positioning of the diff caps to one and other, the M86 is some 55 mm further aft.

 

Cheers

 

John

[PeterAllen]

John - Don't you need to consider the diff in a 'whole of drivetrain' approach? If you cannot achieve a direct alignment for jurid couplings won't you have to pitch the diff at the same angle as the engine/gearbox for the yoke/spider universals? I didn't finalise the diff until I had the engine and gearbox installed and I made the gearbox and diff mounts at the same time.

[Sirpent]

Hi Peter,

 

The M86 will be able to be pitched by adjustment height of the forward brackets, however I will retain the yoke center line, this will mean that the diff will be offset more so to one side resulting in unequal length axles but this will be marginal also.

 

The rear carrier therefore requires a diff mounting coordinate, this wont change neither will the axle positions apart from their height within the cradle due to pitching the diff, nor the the lower cradle beams or forward control arm mount.

 

So end result is the cradle can be fabricated as long as that rear diff mount point can be set.

 

Hope my insanity makes sense.

 

 

[PeterAllen]

John - I'm raising these points as much for my own curiosity as anything.

 

Why, if you are not having a direct alignment are you bothering to align the diff in one plane (with the associated unequal length driveshafts) but not the other.

[Sirpent]

OK,

 

I think we need to be on the same page first.

 

I have attached a diagram of the positioning, you will see that the driveshaft representing the diff yoke is placed in the same plane as far as height within the cradle as was the R180 meaning that the axles although unequal length will sit 5mm higher than the R180's.

 

The yoke is centralised relative to the cradle or perpendicular along the entire cars centerline.

 

Therefore I am maintaining the diff yoke height positioning, along with the axle heights within the cradle but trying to avert the problem you faced with your diff almost skimming the tunnel side wall.

 

Now if I am wrong in my thinking, for God sake, someone come out and mallet me, that includes you too Pete LOL