Silvermine Motors Wilwood Brake Kit/Disc Conversion, Dual Masters

[Ben280]

Hey HybridZ crew! 

 

So I finally decided that after upgrading nearly every other component on the chassis of my Datsun, and a couple really lack luster performances, it was time to do the brakes! I was suitably frustrated with their lack of grab that I started to look into other options. Since this is primarily an auto-x car, I wasn't too concerned with heat dissipation and brake fade like on a serious wheel to wheel machine, and I was more concerned with keeping my weight down. 

 

Here's the car, zooming around at Nissanfest this year at Evergreen Speedway.

 

 

With those factors in mine I went shopping and settled on the Silvermine Motors "Small" wilwood kit. It has the forged 4 piston Dynalite calipers up front and the billet 2 piston dynalite in the rear and traditional drilled and slotted rotors, rather than 2 piece rotors The kit also comes with all the lines needed to connect to the factory fittings. It even has the little retaining clips that always shoot off and get lost under work benches when you pull the stock lines!

 

Edan at Silvermine was excellent to work with and guided me in the right direction on a couple things. 

 

Fastest shipping I've ever had on a part. Think he put them in the mail Thursday afternoon, and I had them in my hands on a Monday!

 

Boxes contents all laid out!

 

 

Well packaged, and everything in its place! Comes with some awesome 10.9 grade hardware, the only bolts you reuse are the front brake caliper bolts, which hold on the new brackets. Really well made and well thought out kit.

 

The rear install is a breeze, once the drum backing plates are out of the way, and the ebrake cables are gone! Hey, its dead weight right? Since the Silvermine kit uses a 3 bolt rear bracket, I didn't need to pull the whole rear assembly apart, so I just turned the rear drum plates into pizzas! Just cut to the bolt holes and then flex them a few times, and they snap right out. 

 

 

 

The whole rear install probably took about 40 minutes start to finish. For my method, you don't need any really crazy tools or huge breaker bars, just a reasonable quality angle grinder! You could absolutely take the stub axles out (and it would be a perfect time to do rear wheel bearings) if you wanted to keep sparks to a minimum. Part of me wanted thought to see if it was possible without removing the axles, which makes this job MUCH less of an endeavor. 

 

The caliper mounts at the 10 o'clock position, keeping its minimal weight inside the axle line of the car.

 

 

The front kit goes on super nicely. Remove and save the caliper bolts, and then remove the hub/rotor assembly. Why Datsun did it this way is a mystery to me, but oh well. I wire wheeled the mounting surface on the hub and the rotor, as well as chamfered the mounting edge of the bore on the rotor to ensure a solid mount. Bolt the hub back together and then put your new rotor on!

 

 

Bleed and you're done! 

 

Overall impressions, these were really well made, I give them 2 wrenches out of 5 for installing. Depending on how you decide to remove your drum backing plates, it goes up to a 3 or 4 out of 5, particularly for a new to Datsun mechanic. I'm racing the car this weekend, so hopefully I'll have developed an opinion about the brakes this time next week! 

Edited May 18, 2015 by Ben280

[helghast7]

Nice! Looking forwards to your after track opinion on the setup.

[RebekahsZ]

What pads are you going to use?

[terse]

So you you no longer have an ebrake?

[Ben280]

What pads are you going to use?

 

Decided to start with the BP-10's, since they are billed as a low heat threshold pad, and are in theory less aggressive on initial bite. Will see how they work, excited to try out some other compounds once I get this setup dialed in. 

 

So you you no longer have an ebrake?

 

Ebrake is gone! But, my garage is pretty level, and I usually leave it in gear when parked anyways. Not a street driven car anymore so I was fine loosing that functionality. I'll update with if that was a smart move or not!

[str8pipez]

Perfect timing, debating this set up now.

[Ben280]

Post weekend update! First weekend racing with the new setup, and I'm impressed. The kit is awesome for sure, and I my math was in the ballpark for the master cylinders. 

 

If you are going to go through the effort of installing disk brakes, I HIGHLY recommend a dual master setup. These pedal boxes are fairly conducive to the needed modifications, and several users here have already made parts/modified their boxes. 

 

 

Parts I used, Wilwood Balance bar 340-1757, a 3/4" and 7/8" masters 260-3374 and 260-3376 respectively and the remote adjuster, cause I could! (340-4990). Wilwood does a really nice job providing all the measurements/drawings for their products, so all that is really required is some figuring on the bias bar! I moved the center pivot point on the pedal up 1/2" to get a better motion ratio on the pedal. That is to say, longer throw, but more pressure! 

 

The bias bar extends through the pedal box, so you need to cut the sides out. This was a little trial and error for me, figureing out where it was binding or not. 

 

 

I used a hole saw to make each end, and then connected them with an angle grinder. I should have made the cutout follow a more angled path, so the hole isn't as pretty as it could be. 

 

 

After the cutouts were made, I drilled the holes for the masters (another hole saw) and welded some bolts onto the backside, and then drilled the firewall for to accept some the new studs! I also had to measure and add some additional thrust washers on either side of the balance bar. Its important to keep everything even on the bar so its easy to adjust. The thrust washers keep everything aligned and free of binding. I decided to keep the setup fully bolted together and go into the car as a unit. 

 

 

Got everything in (had to make a larger hole, again, more hole saw!) and then bolted up the clutch master. 

 

 

Mounted up the remote masters and a local hydraulic shop got my lines sorted out.

 

Bleeding Wilwood calipers is a little weird since they have 4 bleed screws. The top two are the ones that matter, outer screw first then the inner. Always bleed a new master cylinder first! 

 

Once it was in the car, I had to fiddle with the bias bar. In the neutral position, the ratio is VERY rear heavy. I fiddled with it for a bit and got it just about perfect! Hooked up the adjuster knob and project done!

 

Final thoughts on the kit. Very good performance, ratio of front to back grab is great. The BP-10 pads have a very predictable grab characteristic and stop quickly without being too wild. Compared to stock pedal feel, the transition is very good and feedback is great even at the limit. The whole kit is easily installed and well thought out. 

 

Perfect timing, debating this set up now.

 

Its a great setup for sure! Nice and light, and after messing with them this weekend, PLENTY of stopping power. 

[Ben280]

Ok, thought after about a year of running this kit, I'd come back for a follow up, particularly for all you track guys out there! I've done a full season and a half of auto-x, and 3 track days (two at Oregon Raceway Park, one at Portland International) and I've been able to further develop the setup for the car.

 

First off was adjusting the brake bias. Even with a small rear caliper, I had to adjust the bias forward to keep the back from locking well before the front. With my dual master setup this was super easy, just a few twists of a knob. If you were doing this on stock power brake system, I imagine you would want to remove as much of the distribution and proportioning blocks as you can, and then install an inline proportioning valve.

 

Easy way to tune brake bias, just take runs at the track/auto-x area and have someone watch as you drop the hammer on your brakes. You want them to lock at about the same time, and dial your adjuster in the appropriate direction. Video is very useful if you are a solo operation. 

 

Second off was tuning for the pads. Originally I got the BP-10 that came with the kit, which were fine for most of the auto-x stuff, and held up through 1.5 track days before glazing and becoming 100% useless. Useless to the point that I was bleeding and flushing the brakes mid event trying to solve my weak brakes. I realized that I had probably cooked the pads at the ORP day and swapped them out for some Hawk Black pads. These pads with this brake kit will stop a freight train. After a full day at the track with 0 fade in pedal feel or initial bite (running 40 min sessions) I can get behind these! I will say they are VERY dusty, and when the dust gets wet, well, don't let it get wet. 

[Leon]

Love the car and setup, thanks for the feedback!

[JMortensen]

I'm running Black pads too on Coffey's recommendation. He said they were OK for autox after the first application. I just dragged the brakes up to the starting line, never had a problem.

[RebekahsZ]

What happens if the dust gets wet?

[Leon]

[Ben280]

What happens if the dust gets wet?

 

It turns into this really odd rust/krypton coating that is really tough to remove and fairly corrosive to aluminum wheels. I've been having to deep clean my wheels after each event since they have polished aluminum lips. Need to try out various wheel wax strategies!