Hey guys,
When doing a s13 Silvia NA brake conversion do you have to remove the 1200 disc hubs and fit drum hubs or can you get away with just using the 1200 disc hubs? I noticed this on the S13 Page under steps:

1. Get 1200 disc struts
2. Obtain hubs from 1200 drum struts
3. Fit longer wheel studs to the hubs
4. Remove the 1200 disc hubs & fit the drum hubs
5. Obtain matched set of S13 rotors & calipers & caliper adapter
6. Machine rotor centers from 68 mm out to 70 mm to clear the 1200 hub center
7. Bolt on the caliper adapter, slip on the rotor and bolt on the caliper
8. Fit a new lower half brake hose and bleed the brakes

Cheers

Drum hubs are recommended, but later on it says:

Quote:

Also if you use the drum hubs you have to space the caliper back. If you use the disc hubs then you don't but you have to machine the O.D down to fit inside the S13 disc. One issue I found with the drum hub setup was that there is no spigot location to centralise the disc either.

No spigot? Looks like it has it to me?

Drum hub vs disc hub

The O.D of the hub register is smaller than the I.D of the S13 rotor. I was going to make up a tapered ring to locate the I.D of the rotor but I went a different way all together. You can see in this pic that there is clearance on the ID.

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Great info. How'd you solve it? And are those early or late drum-brake hubs?

Drum brake hubs
* 1970-1975 small spindle
* 1976-1985 large spindle

The early drum hubs should have 68mm hub reg, same as the S13 rotor hub reg. It doesn't matter for most wheels, because they center on the tapered lug nuts, but the slip-on rotors need a good fit.

I didn't solve it I decided to use S13 struts instead. I think the hubs are actually 120y because the struts had the mounts for under the tower, they were small spindle. In answer to WackDatto's question I think it is easier to use disc hubs and machine the O.D to clear the rotor.

I have built a few sets of s13 brake conversions on drum hubs a few times. I machined the old drums into spacers disks to correct the offset issue. It worked a treat. The drums are the correct thickness and locate on the hub just right.

Using a hub/wheel spacer creates an issue
* Original offset is preserved by using drum hubs
* spacer reduces amount of dish in the wheel you can get away with

However using a 5mm spacer on the hub, or a 5mm spacer on the caliper bracket, is needed for the Kev Rowley S13 Brake adapters which are designed for the fatter disc hubs

Thanks guys,
Also when using 1200 drum hubs on 1200 disc struts do you have to use a caliper spacer aswell as a bracket? I'm planning on using a Kev Rowley bracket. Also do you have to use longer wheel studs ie s13's? The car have 15inch wheels at the moment.
Cheers