Volvo Portal Axles Under My HZJ78 Troopy (1 Viewer)

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Lethbridge? Crikey, you are in the neighbourhood, and i will have to visit. A Pinzgauer? One step closer to heaven...
 
It is neat to witness the off road ambitions of various people. Your interest is good to see, and here's a reminder you don't need: do it your way, come hell or high water.
Thanks, I usually do things my own way, no matter what others say.

The guy in the UK that is replacing my cw&p's and rear axle housing/half shafts is hanging on to them for another 5-7 weeks, to have a gear cutter make up some more 5.99:1 ratio cw&p's using mine as a template.

So, hopefully once that is done, my replacement parts should be on the way.

Will speak to my engineer before then, finalise some details of how I have to do things, and what it will cost, then I'll have to save up to get it all happening.
 
In my HZJ78, the rpm at 110kph (highway cruise/maximum-posted speed here) in 5th gear, based on the Volvo 5.99:1 ratio portal axles + HZJ transmission (standard or with greater overdrive 5th gear) + HZJ transfer (standard or with Marks4WD overdrive high/underdrive low) + 37" tyres are as follows...

- Standard Toyota axles + standard transmission + standard transfer on 32" tyres = 2587rpm @ 110kph in 5th (for comparison of the options below to standard HZJ78 ratios/rpm)

- 5.99:1 Volvo Axles + overdrive 5th transmission + overdrive transfer = 2378rpm @ 110kph in 5th (gives underdriven 1-4 gears, and overdriven 5th, compared to standard)

- 5.99:1 Volvo Axles + higher overdrive 5th gear in transmission + standard transfer on 37" tyres = 2585rpm @ 110kph in 5th (gives underdriven 1-4 gears compared to standard, 5th gear same as standard, higher gap between 4th and 5th)

- 5.99:1 Volvo Axles + standard transmission + overdrive transfer on 37" = 2867rpm @ 110kph in 5th (gives all 5 gears underdriven compared to standard, but with standard spread between gears)


...so, I can get very close to standard gearing at highway speed, with slight compromises in terms of gear spread and overdrive/underdrive amongst the 5 gears depending on which option is chosen.

I am still not sure which is the best option at the moment.


These are the results from the gear ratio spreadsheet I used to calculate the rpm/speed for these 4 options...

VolvoPortalAxleHZJ78gearratiocalc.jpg
 
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Hey Simon of oz!
What's latest on you build?
Am sticking c303 portals under an hzj80. It's hectic as we have an event june 3!

Currently awake at night fearful the. Shafts won't hold up!

Any thoughts on shaft strength?

Landmawe in Kenya
 
Hey Simon of oz!
What's latest on you build?
Am sticking c303 portals under an hzj80. It's hectic as we have an event june 3!

Currently awake at night fearful the. Shafts won't hold up!

Any thoughts on shaft strength?

Landmawe in Kenya
Hi Landmawe,

I am still waiting for replacement 5.99:1 ratio cw&p and right hand offset rear axle housing/half-shafts to come from the UK. The guy that is sending the replacement parts wanted to hold on to them a little while longer to have some aftermarket 5.99:1 cw&p's made up for spares and sale.

Probably a good thing, as I have not really had any spare cash to pay for import/customs/quarantine duty/charges/etc. at the moment, as I sort of got sidetracked in buying this (the car, not the sat dish), which has been sucking my money for the last couple of months...
SimonsSpiritRTidbinbilla.jpg



A set of Volvo portals under a 80 series sounds like a good idea, have you seen the build threads for the 80 series with Volvo portals that are already on these forums?

They are supposed to be pretty tough axles, apparently you just have to make sure the bearings in the portal boxes are adjusted properly.

There are aftermarket half-shafts available, and CV joints, but I have read that some of the aftermarket axle shafts are not as flexible as the factory shafts, so don't absorb the shock as much and transfer it to other components in the driveline.
 
Hi Landmawe,

I am still waiting for replacement 5.99:1 ratio cw&p and right hand offset rear axle housing/half-shafts to come from the UK. The guy that is sending the replacement parts wanted to hold on to them a little while longer to have some aftermarket 5.99:1 cw&p's made up for spares and sale.

Probably a good thing, as I have not really had any spare cash to pay for import/customs/quarantine duty/charges/etc. at the moment, as I sort of got sidetracked in buying this (the car, not the sat dish), which has been sucking my money for the last couple of months..

A set of Volvo portals under a 80 series sounds like a good idea, have you seen the build threads for the 80 series with Volvo portals that are already on these forums?

They are supposed to be pretty tough axles, apparently you just have to make sure the bearings in the portal boxes are adjusted properly.

There are aftermarket half-shafts available, and CV joints, but I have read that some of the aftermarket axle shafts are not as flexible as the factory shafts, so don't absorb the shock as much and transfer it to other components in the driveline.

This LC80 (TDI) has had the Volvo portals and 46" tires for two years with no problems at all, much tougher axels than I thought. It has custom diskbrake conversion.
DeliverFile.aspx
 
This LC80 (TDI) has had the Volvo portals and 46" tires for two years with no problems at all, much tougher axels than I thought. It has custom diskbrake conversion.
DeliverFile.aspx

That is a tough looking 80 series, very nice!

I notice that you are in Iceland, do you have any idea where I can buy some Artic Truck style flares for the 70 series?

Artic Trucks will not sell them unless they are fitting the flares to the truck themselves.
 
HI @SimonInAustralia not sure if thread is still going like yo know how you went with all your portal axle set up on 75 series as I have brought a Volvo C304 myself and am chasing some portal pasts myself thanks Justian
 
Might be good news for these boys that Northwestfab has a low range adapter or high range adapter that can turn portals at highway speeds... Although I think the overdrive has not been developed I would contact the guys..

So you guys could be running the over drive withportals for better highways gears...JUST SAYING...

My friends at NWF for over ten years...


NWF BLACKBOX UNDERDRIVE
BlackBoxLogo.png

The Blackbox Series is NorthWest FabWorks premier line of shiftable, underdrive gearboxes.Typically mounted between the transmission and transfer case, the BlackBox is a gear reduction unit that has the ability to shift from a 2.72:1 low range back to 1:1 for existing operation.

Original%20Black%20Box%20Cropped.jpg


Released in 2005, our original Blackbox set the benchmark for advanced planetary technology. Since then, the original BlackBox has evolved into a complete product line with dozens of application combinations. The BlackBox offers a gearing solution for everyone; from the weekend warrior, to a top truck challenger.




What Advantages Does The BlackBox Low Gearing Offer?
Going from a vehicle with a stock, or single transfer case will see a massive improvement when adding the BlackBox.Remember the control and traction you gained from that first locker, or set of new M/T tires when you first started out?That is the type of substantial increase in capability you can expect after installing a BlackBox.

Operating a vehicle with the right gearing, and thus RPM and wheel speed for the terrain at hand is key; too low of a crawl ratio and your engine is revving high, but the reduction is too deep and you may not build enough momentum to pop up over that rock face or ledge.Too tall, or not enough gear reduction, and the lack of control leaves you with no choice but to try to bounce off obstacles at speed.

Having an extremely low crawl ratio isn’t the key goal; the ideal 4x4 has not only low gears, but gearing OPTIONS.Let’s dive into that next...

Having the right gear, at the right time:

There are a few ways to add gearing to your 4x4:
1) Lower Differential gears:
re-gearing your axles for larger tires can be necessity for driveability, however installing an axle ratio too low for your engine/tire size can leave your engine screaming on the highway to the trail, however still not offering any real substantial gear reduction.

New Transfer case gears:

You may consider a lower aftermarket gearset for your existing transfer case.There are quite a few kits out there to re-gear your current transfer case into a deeper low range, or install an aftermarket transfer case like the Atlas II. While generally good kits, this option leaves you with only one low range, and no gear selection.
The final choice, the BlackBox:

Black%20Box%20Split%20Thumb.jpg
Gear selection of multiple low range ratios will give your rig the control to tackle any terrain with the precise level of power required.You will have the ability to decide exactly how fast (or slow) to approach obstacles, applying torque smoothly, with less stress and shock loads placed on your drivetrain. This means more trails tackled, with less repairs.


How does the BlackBox offer so many ratios?

Adding the blackbox not only offers the 2.72:1 low range, but has the ability to multiply against your existing transfer case low range offering 4 total low range options. Lets use a NP205 for a gear ratio example below:

BlackBox & Transfer Case in High range: 1:1, no reduction.

BlackBox in high, Transfer case in low,ex:1.96:1 (NP205)

BlackBox in Low, Transfer Case in High, 2.72:1

Blackbox and Transfer case in Low5.33:1 compound low. (2.72:1 x 1.96:1)

As you can see, adding the Blackbox to your drivetrain not only gives you a lower ultimate ratio, but additional ratios along the way. It is this gear selection that the Black Box provides that makes it the clear cut choice and gives the ultimate flexibility. Gear selection is #1 when it comes to building a vehicle that can conquer all types of situations and terrain.
Competitive Advantage.

At NorthWest FabWorks, we're not going to produce a product unless we're sure that we have the best available. The Black Box is no exception, holding a strong competitive advantage over all other underdrive units on the market today:
Black%20Box%20Output%20Bearing%20Thumb.jpg
Heavy Duty Roller Bearing Shaft Support:
The Black Box is the original planetary gear box to have a bearing support at both the input and output of the mainshaft. Our competitors rely on the input splines and bearing of your transfer case to both center and support all the output load of the gearbox. Not here. We use a massive 80mm roller bearing at the output of the Black Box.
Adjustable Shifter Assembly:
The Blackbox utilizes a versatile shifter mechanism that allows the user to infinitley adjust detent pressure for hi/lo shift. This shifter features hardened detent locks, shifter fork, and serviceable shift fork pads.
Hard Anodized Black:
All of our Black Box Gear Boxes are hard anodized black, giving a lasting consistent surface finish.
Output%20Stack%20Thumb.jpg



The BlackBox uses a 8620 Mainshaft that has been case-hardened and hard turned for the ultimate in shaft strength and precision. Looking for a weak link? Look elsewhere.










Billet Input Retainers:
The Black Box includes a billet input retainer with quad oiling ports. We do not re-use factory cast NVG231/241 retainers. Our retainers parts are purpose built specifically for the Black Box.
BlackBox%20Shifter%20Thumb.jpg
Cable Shifter:
The Blackbox includes a rugged cable shifter for easy operation from hi to low. Couple the Blackbox with one of our dual cable shifter kits and we can provide a triple shift box for an extremely clean setup.


360 Degree Clocking:
The Black Box Will allow you to rotate your transfer case 360 degrees. There is no limitations on orientation with the Black Box. No need to buy a clocking or flip ring, its built in.
Knowledge:
We've been in the underdrive business for ten years, and we manufacture the vast majority of the BlackBox parts in our manufacturing facility. Our expert employees have the experience and knowledge to guide you from application fitment to trouble shooting. You can rest assured we here for our customers.

The Evolution:

BlackBox%20Group%20Thumb.jpg


Since conception, we have continuously grown and improved on the technology. We now have the shortest, strongest, and most diverse underdrive line available on the market today.
The BlackBox line has expanded into these diverse lines, each offering a key innovation:
BlackBox – Original, The classic that started it all.

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Eco-Crawl: A DIY builder version.BlackBox technology on a budget.



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Rob:cheers:
 
I believe Rob's post speculated on development of a version of the Black Box that would function as an overdrive:

"Might be good news for these boys that Northwestfab has a low range adapter or high range adapter that can turn portals at highway speeds... Although I think the overdrive has not been developed I would contact the guys.. So you guys could be running the over drive with portals for better highways gears...JUST SAYING..."
 
I just don't understand why you would spend money on portals like this for a relatively low return on the investment. If the goal is to not sink in snow why not just get a set on mattracks that bolt right up in place of your wheels and call it good? We had them on many of our trucks in Antarctica and they worked great...
 
I just don't understand why you would spend money on portals like this for a relatively low return on the investment. If the goal is to not sink in snow why not just get a set on mattracks that bolt right up in place of your wheels and call it good? We had them on many of our trucks in Antarctica and they worked great...
How many hwy miles did you do with those mattracks getting to the sno/ice In Antarctica? He is making an all round expedition rig. Not an Antarctic rig.
 
Hi.
Nice build!

How this project is progressing?


I have two Toyota Land cruisers with volvo portal axles.

80-series with 1HD-T engine and manual transmission, 38,5" mickey thompson

60-series with 12H-T engine and manual transmission, now days 40" Maxxis competition trepadors



Sorry for messing your build topic

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Hi.
Nice build!

How this project is progressing?


I have two Toyota Land cruisers with volvo portal axles.

80-series with 1HD-T engine and manual transmission, 38,5" mickey thompson

60-series with 12H-T engine and manual transmission, now days 40" Maxxis competition trepadors



Sorry for messing your build topic

View attachment 1299652

View attachment 1299655
Wow, got some specs on the 60, it looks bobbed front and rear...?
 

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