Fiat 124 Spider with Argenta hubs

[Sandro]

Guys

there has been a few posts recently on this and I am considering this modification as part of a restoration. I just wanted to know what the benefits are for a car that will only be used on the road , not race or rally..just so I can work out wether or not its worth doing.


thanks

Sandro

[Guy Croft]

There is nothing wrong with Fiat Spider hubs as far as I know, but there certainly have been serious problems with the knuckle (or ball joint) parts. Is this the reason for the conversion?

Dunno..

Re failures here is a very informative post from Thad Kirk in the USA which is very well illustrated and has some good contacts in it.

http://www.mirafiori.com/~thad/balljoints/bj.html

G

[Sandro]

Hi Guy

thanks for the reply...the reason for the converson is I have read the Argenta/132 hubs are taller between the mounting points, lower the car and give better handling... I just want to know if these performance is worth it on a std road car...

The ball joint issue I have read about, I have ordered the Federal Mogul (Moog) ball joints as we still make them, they seem good quality....

thanks again

sandro

[Guy Croft]

Oh, OK

G

[Guy Croft]

SP - Is this the same topic?


http://guy-croft.com/viewtopic.php?f=14&t=2538

G

[Simon]

TR-Spider explained this in my build thread with some pictures of the two parts. I think the main advantages are bigger bearings and improved camber control throughout the arc of movement due to the altered wishbone angles.

viewtopic.php?f=5&t=2141&p=13917#p11178

[cstorry]

FYI - the volumex spider also used the 132 front hubs (and rear diff as well - more or less but that's a different story).

The volumex spider also extended the front and rear track and had different springs/shocks.

Chuck

[tmvolumex]

Chuck,
Since you mentioned the Fiat 132 rear diff was used on the Fiat 124 Volumex spider I have a question. Was the entire rear end the 132 or just the internals of the diff 132 components? I assume the 132 diff was used on the Volumex spider because it is stronger. The 131 diff is notorious for being weak. Do you know if the 132 internals (ring, pinion carrier) fit in a 124 / 131 diff housing?
Tom

[ace124]

There are 2 types of 132 differential.
Put simply, one that pulls out the front, or one that has a plate with access thru the back of the diff.
Neither type can have its internals transfered to an early 124 type diff housing.
Both types of complete axle can however be modifyed to fit into a 124.
You will need to cut and reposition the brackets. 132's did not run a panhard rod, so they had angled track rods which were parallel in a 124.
If you have them both side by side you can easily see what needs to be cut and rewelded.
Ive done it on both types when i couldnt get 124 differentials and its pretty straight forward.
The down side is the weight, both 132 types are a lot heavier.
There is no need for a 132 diff in a 124, even on a circuit car. I know of a 16v RWD twincam sports sedan with 275HP that ran a 124 crown and pinion for many seasons without any issues. Set it up right and it will be fine.
If your drag racing then consider something different again.
Most 124 diffs fail because the front pinion nut looses its preload on the pinion bearings, thus allowing the meshing backlash and alignment between crown and pinion to wander. When this happens its just a matter of time before the tolerences increase to the point that unbearable stress is placed on the components and they give. Mostly it will be the pinion gear. Have this crack tested if rebuilding your original. Star gears can also fail, but lets face it, these things are 40 years old now!
I recently rebuilt 3x 124 type differentials with LSD's. All had a story to tell inside, be it wear, lack of oil, or loose bearings.

[TR-Spider]

Ace, I agree on what you said about the diff geometries,
however I diagree on this

There is no need for a 132 diff in a 124, even on a circuit car. I know of a 16v RWD twincam sports sedan with 275HP that ran a 124 crown and pinion for many seasons without any issues. Set it up right and it will be fine.

I used an early "Banjo" type 124 diff (from 1600/1800) as I could get a LSD-insert for these. And I went through an alarming rate of the side bearings with trackday driving with sticky yokohama semi-slicks (4 within 1.5 years, if I remember correctly). It was not oil temperature (checked that). The bearings were apparently just squeezed to death from the load peaks which the combination of LSD and semi-slicks apply into the diff. Opposed to running an open diff and street tires, where load peaks are sliped away at the wheel.

The 132 axle with its substancially bigger bearings is a good choice here. Beside the panhard rod connector also the 2 inner arms connectors need to be fitted.

Thomas

[ace124]

Thomas, i totally agree about the bearings being bigger. It makes perfect sense they will be more durable allround.
I base my response on the 124 coupe sports sedan everyone knows down here in Australia.
In fact there are 3 similar spec cars running on and off, with the said differential with a lot of power, slick tyres and LSD.
Infact i know one actually runs a locked 124 differential with no issues.
The car i refer to with 275HP has never had a diff issue either.
If your side bearings are being 'squeezed to death' and its not an oil quality or temp issue then im at a loss on that one, unless the diff is being set up with already too much bearing preload/cap spread. I cannot remember the spread specs off hand,(if my DTI is correct in that pic then 0.17mm). They are as per the Fiat manual, and measured with a DTI off the top of the cap housing as per my pic. I dont think anyone has the original Fiat tool used for this anyway.
Ive also seen 124 differentials fitted with crude cooling fins.
Are you using VAZ/Lada bearings? or is there something else available in your country?
Maybe someone else can comment. Id like to know more also.

[cstorry]

Tom

... as has already been stated. Basically the whole 132 unit with the additional brackets.

I believe that the track is wider than the stock 124, the axles and bearings larger and the ring and pinion are different ratio from any Argenta/132 that I am aware of.

Chuck

[TR-Spider]

Ace,

I got the diffs from 2 different shops (both specialized on older Fiat) , with new bearings every time.
I never did any adjustment myself. Always used best quality oil and checked temperature, which was never bigger than 85°C. Maybe once the failure was related to a bad quality (probably Lada) crown+pinion set, which was rather noisy.

I just got annoyed after the 3rd time, and modified me a 132 axle, and that was it.

Sorry, but can't tell much more.

Thomas