125 Stub axles, Whoa brakes and a 124 Spider

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ITA124
Posts: 128
Joined: Wed Nov 12, 2008 1:51 am
Your car is a: 1976 Fiat 124 Spider
Location: Sydney, Australia

125 Stub axles, Whoa brakes and a 124 Spider

Post by ITA124 »

Hi All,

Thought I'd take the time to give you some information on replacing 124 stub axles with 125 items, in addition to WHOA brakes.

I haver a 124 spider with WHOA brakes. They're great. Easy installation and great performance. They've been on the car for a couple of years now. With the Fiat Nationals coming up, I though I would upgrade the front end to thicker 125 stub axles to handle the greater loads of sprinting and also lower the car.

So I've sourced a set of 125 units and given them an overhaul (Thanks Sideways), jacked the car up and ripped apart the front suspension. Installed all the new equipment. Eveything was going well until it came time to mounting the caliper. Guess what, it didn't fit. Wilwoods, being fixed calipers, need to align to the rotor. The 125 stb axles being wider, increases the gap between the rotor and the caliper mount. This isn't a problem with standard calipers as the offset is taken up by the floating caliper.

So I could put a spacer between the caliper carrier and the stub axle to take up the slack. This won't work as the 125 hub is a larger diameter than the 124 unit and the carrier will snag on the hub.

So in summary. If you've got Whoa brakes to fit a 124, you can't fit 125 stub axles. Refer photos

Here are some dimensions that I have measured between 124 and 124 stb axles. All measurements are in mm

.............................................124..........125
Hub Dia....................................65...........67
Spindle centre to lower ball joint.......66...........72........lower the car by 6mm
Stub axle height........................144.4.......162.2......this raises the upper control arm closer to the bump stop
Larger journal............................26.16.......31.78
Small journal.............................19............19........Same axle bolt and dust cap
Disk to carrier face.......................63............67.30...misalignment dimension
Disk to carrier............................1.8...........6.5......misalignment dimension

Image
..............Whoa carrier on a 124.......................Whoa carrier on a 125


Image
Last edited by ITA124 on Thu Dec 10, 2009 7:12 pm, edited 1 time in total.
Paul


Fiat 124 Spider (Big Red Car. So my son tells me)
Toyota Corolla AE86 (Fiat as a daily driver? Not)
Fiat 128 Rally (Why did I sell this car?)
Fiat 124 AC (An iron ore waffle shaped like a 124. Donated to Sims)
Fiat 128 SL (First fiat)
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manoa matt
Posts: 3442
Joined: Thu Oct 26, 2006 4:28 pm
Your car is a: 1978 Fiat 124 Spider 1800
Location: Honolulu, Hawaii

Re: 125 Stub axles, Whoa brakes and a 124 Spider

Post by manoa matt »

Paul,

I saw your post over on Turbo124.com and I wanted to reply, but I'm not a member of that forum yet. Anyway, regarding the specifications, Does it only lower the car by 6mm? 125 stub axles are hard to come by here in the states. Seams like a lot of parts searching for just 6mm. Raising the upper control arm closer to the bump stop does not sound like a good idea.

I'd be nice if someone made true drop spindles for the 124, instead of cutting springs to lower the car.
User avatar
ITA124
Posts: 128
Joined: Wed Nov 12, 2008 1:51 am
Your car is a: 1976 Fiat 124 Spider
Location: Sydney, Australia

Re: 125 Stub axles, Whoa brakes and a 124 Spider

Post by ITA124 »

I like to share the love on both forums.

The main benefit of 125 stub axles is the beefier spindles. This comes at a cost though. The taller height does make the upper control arm closer to the bump stop. To the point where you either cut your bump stop or drill out the spot welds and relocate the assembly. Further to this, the increased angle on the upper control arm changes the geometry as the suspension compresses. There are many good posts on this.

As for lowering the car. There are many posts on the variation the car is lowered. I don't know where these come from. I went over the two stub axles with a vernier and what you see from the measurements, this represents a delta of 6mm.

Drop spindles? There may be a market
Paul


Fiat 124 Spider (Big Red Car. So my son tells me)
Toyota Corolla AE86 (Fiat as a daily driver? Not)
Fiat 128 Rally (Why did I sell this car?)
Fiat 124 AC (An iron ore waffle shaped like a 124. Donated to Sims)
Fiat 128 SL (First fiat)
RicambiStorici

Re: 125 Stub axles, Whoa brakes and a 124 Spider

Post by RicambiStorici »

Hi there,

we have at the shop the kit to transform your Fiat 124 hub/spindles to Fiat 125. We have NOS parts and a kit of used part in very good condition ready to be installed at your car.

Please see the photo of the USED kit (very very good condition quite NEW):

- All the parts in the photo 1 (complete kit), weight is 12kg. Price of the kit is 220,00 euro.

- Only the parts with green cross in the photo 2, weight is about 9 kg, price of kit 195,00.

You can see the photos (photo 1 and photo 2) at this link:

http://www.ricambistorici.com

choose photogallery then Fiat 125 and you'll find Photo1 and photo2 with the complete kit.

We can supply the same parts NEW but price are higher, you can ask me for that by email, our company is in Italy and we have a big warehouse with more than 40'000 part numbers Fiat Original for all the brand of Fiat Group, Fiat Auto - Lancia - Alfa - Autobianchi - IVECO and so on...

I'm trying (in the spare time) to classify the spare parts car by car but it's huge work, I made some photos of the parts we regularly sell to our customers in US - Europe and Australia, but you can ask me everything and I'll verify what we have in the warehouse (first of all mechanical parts, but we have also body parts and engines) from 60s to 2000.

Writeme an email at ricambistorici@gmail.com
sydh70

Re: 125 Stub axles, Whoa brakes and a 124 Spider

Post by sydh70 »

Hello,

I am changing my 124 spindles for 125 ones on my 124 CC1.
Everything was going well too until it came time to fix the caliper bracket.

ITA124 wrote:Hi All,

The 125 stb axles being wider, increases the gap between the rotor and the caliper mount. This isn't a problem with standard calipers as the offset is taken up by the floating caliper.
In fact it is a problem (maybe in a lesser degree) as the caliper bracket will be in collision with the disc...
So what could be the solution ? To ad some washers (and longer screws) in order to offset the caliper bracket ?

And it seems that 125 spindles increase track width..?!
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