Anyone know if and how much a Wilwood hub (for ventilated discs) changes the tracking width (compared to say stock discbrakes)?

I'm looking at changing my current homemade discbrake system to a Wilwood system for weight savings mostly.
But since there is nothing useful made as a kit from Wilwood, I'm piecing together a setup that fits my '73 Dart.

I already have a pair of Forged light 4-piston calipers with 1.38" pistons, and a pair of 12.2" rotors:
https://www.wilwood.com/Rotors/RotorProd?itemno=160-0277

This is what I'm looking at:
Hub:
https://www.summitracing.com/int/parts/wil-270-8775

Adapter:
https://www.summitracing.com/int/parts/wil-300-3099/overview/

Still need to find/make the caliper-bracket from the stock '73 Spindle to the Wilwood brake caliper if I proceed with this.

I don't want the wheels to be moved to the outside if possible.
My current discbrake setup is using '73 Chrysler rotors and calipers.
When I installed this system some years ago, I was pleasantly surprised the tracking width had narrowed by about 3/8" per side I recall. This made tire/wheel-fitting a tiny bit easier.

I have these installed on my 'Cuda. Are there any measurements I can get you with them installed?

They are on an e-body drum brake spindle.

Good question on how to measure with everything mounted.
Although there are a few differences which I think could all mess with backspacing.
I already have discbrake ('73 A-body) spindles on the car, and the Wilwood setup I'm looking at seems to mount and position the adapter (to which the rotor mounts to) 'behind' the hub.
On your setup the adapter, I think is called a 'hat' and mounts 'over' the hub from the front. This alone would increase the trackwidth by the thickness of the hat.

I'll shoot an email to Wilwood to see if they provide any spacing info compared to a stock setup.

Google and little 2nd grade math= +.21"

Wilwood Drag kit uses hub 8777 and they state that kit reduces track to .23" using the 73 spindle

So using that info, we can figure it out

So the rear bearing to hub flange difference between 8777(2.09") and 8775(2.31") is 0.22", .44" total,,so your 8777 hub done ate up all the reduce track that the 8775 was giving x2.

Wilwood calls out +1/8" in track on their site for the e-body kit.

Thanks for the help guys.
Piecing all this together and seeing the costs add up very quickly makes me hesistant to pull the trigger, and all for 'just' some weight savings and possibly ending up with an even little bit wider track-width on my car.
As for brake-performance this will hardly any to no improvement over the current 11.75" C-body rotors and 2.75" diameter calipers I already have on the car.

Wilwood Hub 270-11533 has the shortest rear bearing to hub flange distance(2.06") that still fits that spindle, to give a track reduction

https://www.wilwood.com/Hubs/HubProd?itemno=270-11533

The 8775(2.31") being the widest.

The weight savings is significant in terms of sprung weight, weight distribution and moment of inertia.

Compared to my 10" drums(34.4lb with knuckle and LBJ), [which are feather light compared to your boat anchors] the Wilwood are 10 POUNDS lighter,, PER WHEEL.

For you it'd have to be closer to 20lb per wheel savings,,,which will make acceleration, braking and motion control that much easier.

The 11533 hubs are what I used on my custom build up.

What dia rotors and thickness are you running?

What calipers are you running ?

The weightsavings are still very interesting and something I really want to pursue.

I've decided to keep the '73 C-body rotors (1.25"/11.75") and find a suitable lightweight (street) caliper and bracket that can be used with these.

Since this forum hasn't changed since 1997, its a pain to post pics

10.75" x .81" vented

Forged Dynalite Internal

24.4lb, knuckle, LBJ, Rotor, Caliper

post 213 for pics
https://www.forabodiesonly.com/mopar/thr...post-1972081637

It's not a pain to post pictures.

It is if you don't have somewhere to host ur pics!

Im using the 11533 hubs along with 13"×1.25" spec 37 rotors, aluminum hats and wilwood grand national III 6 piston calipers trailing mounted with custom mounts.

And those weigh more than Willwood’s smallest street rotor 10.75 x .81” caliper combo.

Those two Willwood brake setups placed side by side would br quite a difference.

My setup weighed 41.8lbs...thats with spindle, hub w/ 3" arp studs and lug nuts, bearings, lower bj and steering arm, camber spacers, rotor and hat, calipers and pads and all associated fasteners.

It is heavier than the previous setup posted...i kinda missed the OP asking to lose weight, i wanted a max braking setup! However I do run 18×9.5 wheels that only weigh 19lbs each so that helps balace it out lol

I'm building my Swinger for light weight, sprung AND unsprung.
Its mostly an Autox car so giant brakes are not a priority.

Even the 10" drum spindle is lighter

I think i got this super simple procedure to attach a picture

[file manager,,choose a file,,,add a file,,,,3min later,,What the??ERROR?!?!2mb max?? but its 2018 not 1997 and my pic is 4mb??,,UGH!,,,open pic,,,resize,,,save,,,file manager,,choose a file,,,add a file,,,done adding file]

---Oh Yeah so much easier than CUT,,,PASTE,,,lol

Why not just use the E body drum spindles on an A body with 73+ upper a arms and use the off the shelf Wilwood Cuda kit?

I've been looking around at the Wilwood site and found that if I wanted to keep my 1.25" thick rotors and maintain the current 2.75" (5.94 sq.in) caliper piston diameter, there seems only one caliper that fits the bill, which is a single piston GM replacement-version;
https://www.wilwood.com/Calipers/CaliperProd?itemno=120-5289

I wonder if that GM piston will mount to the stock caliper bracket, even though I would rather have fixed calipers so I could get rid of the heavy stock bracket too.

My current brake system (1973 C-body rotors, calipers & brackets);