The Savvy/Vanco Brake Install: The New Hotness.
You've just avoided death during the grinding of the unit bearings. How do you make sure that you adequately reduced their diameters?
You don't, because mistakes are never made in The Republic of Dave. Trick question.
Call the Psychic Hotline.
Test fit the new rotor.
Correct Answer: B.
I'm lying to you, there...it's A.
Actually, I'm still lying to you...it's D.
I wasn't lying to you that time...you pop the new rotor on and see how well it fits. You could also measure everything if you liked but - due to the chamfer inside the hat - it's much easier to just assign a rotor to a unit bearing and then fit that
rotor to that
bearing flange. Now, checking rotor fitment is usually not difficult at all: if it seats onto the unit bearing it's likely going to bolt up correctly. However, the fitment of these
rotors contains another potential land mine: the interior chamfer on the rotor hats can cause them to feel as if they are seated properly when - in fact - they are not
. Having a rotor solidly bolted when it is not coplanar to the face of the unit bearing can cause lots of damage and can threaten the security of life, limb and sammich.
We'll break the fitment down into two quick segments for those of us that have trouble with long paragraphs. Also: my apologies in advance for everyone having to see another picture of Very Sincerely Yours.
Step 1 - Checking The Diameter of the Unit Bearing:
Easy...bolt up the rotor to the flange. If you've reduced the diameter adequately you'll be able to slide the rotor hat over the unit bearing...if you haven't, you won't. Simple! Secure it with two lug nuts once you're there.
Step 2 - Assuring Coplanar Surfaces:
Easily done, as well. Once the rotor is temporarily bolted on you need to sight down the planes of the rotor faces while you manually rotate the assembly. A non-planar alignment due to the interference at the chamfer area will show up as a slow side-to-side wobble.
Pictured: "Whatever. That's close enough."
Now we're finally ready to assemble some parts, right? WRONG. We've got another
potential pitfall to take care of: the clearance between the lower portion of the saddle and the debris shield, which may be somewhere between "minimal" and "nonexistent." Vanco's instructions direct us to clock the debris shield's lower portion as far forwards
as is possible - the mounting holes in the shield itself are slotted - and here we see why. Although this is not the greatest picture in the world you can see that the shield starts to get really close to the saddle around the area of the lower mount.
It's worth noting that this is a LOT of clearance, comparatively. We were expecting to trim the shield - per Vanco's instructions - in order to make room for the new saddle. Having 1/4" of room was much, much more than we expected. Once the need for additional trimming was dismissed, we could take the saddle off, replace the rotor and then bolt the saddle on in a more permanent fashion with some red Loctite. This is literally the ONLY time I've ever willingly applied red Loctite to anything.
Pictured: The security of life, limb and sammich.
You really don't get an appreciation for the new twin-piston calipers until you see the 12" rotor and caliper saddles assembled next to each other. This was my first real
indication that Greta's braking power was about to radically increase.
Pictured: Mo' betta'.
Pay close attention to the top portion of the saddle: you can see that there is literally less than 1/8" of clearance on either side, between the saddle and the rotor faces. This clearly illustrates the reason you have to be exceptionally careful when deciding to keep or eliminate the debris shield, and it also clearly illustrates that we're finally getting somewhere with this installation. It literally takes more time to make room for the new parts than it does to install them. Here we can see the retaining clips and the new brake pads resting in the saddles. Also, we've got the spacers re-installed and torqued down, and as a bonus: the interesting effect known as "halation."
After this, the caliper slides into place and is bolted down per the instructions. And, holy f***, does it look big...
Wait, I can do better...here's a quick comparison shot on the opposite side. It's almost not even funny. Almost
Once the new calipers were on we reattached the steering linkage and checked the alignment, which turned out to already be at my preferred measurement of 1/16" in, no matter that we were using totally different knuckles. Even more curious: we later found out that the drag link - which had been slightly
off before - was now set at the correct length. Go figure.
At this point we also addressed the last bit of modification work: the alteration of the stock banjo fitting, which until now has remained attached to the stock caliper. The fitting needs to be ground flat on one side in order to fit the new caliper, and when you look at it in juxtaposition to the new caliper it's easy to see what you need to do. To perform the modification we detached the fitting, wrapped a piece of duct tape around the opening to prevent metal/debris contamination, clamped it in a pair of locking pliers and ground one side flat with the flap wheel on the handheld grinder.
If you look carefully at the picture below you can actually see the projection that we're removing: all we're doing, here, is completing the flattening of the half-notch that's already present in the factory fitting. The notch is barely visible above the edge of the flap wheel. We're just going to continue that notch across the rest of the body of the fitting...
...until it looks like this. See? More shiny metal, just like I promised.
This grinding operation takes about...oh, a minute and a half, should you go very slowly, but it would be much
easier to do this if you had the line off and a bench grinder to work with. I'm planning to swap out brake lines in the future and I'd like to think I can find a line that has the proper fitting already in place, but - failing that - I'll make my life simple by completing this modification before the new lines get installed. Either way, all that's left to do at this point is to attach the fitting to the new caliper...which, from this angle, looks even bigger
. How delicious.
Since I spent a LOT of money on these parts I decided to go ahead and spend the extra few dollars that a full bleed-out and fluid replacement would require. And it's a good thing that I did that, because this is what Greta's brake fluid looked like - totally f****** horrific. Note: We don't think that the container shown below actually contains brake fluid. We're honestly not sure what this liquid is, but what we DO know is that it really doesn't seem to have any similarity to brake fluid at all. In fact, it resembles nothing so much as thin, discolored epoxy resin. Other guesses as to its identity included partially-fermented molasses, out-of-date turpentine, and that weird substance that was secreted from the creature that killed Tasha Yar on Vagra II.
The full brake bleed is easy: you start at the furthest caliper and work your way back, bleeding old fluid out at each corner. When new, clear liquid starts showing, you're good to go. This is much more similar to what brake fluid should look like.
Valuable Information: Throw a vertical loop into the tube you use to drain your brake fluid. This allows 1) the bleeder valve to remain open and 2) the person operating the brake pedal to simply pump it up and down at their own pace, without the time-consuming start-stop pattern that bleeding normally requires. The vertical loop prevents air from sliding back into the caliper once the brake pedal is released and pressure comes off the system. We used this method on each of Greta's calipers and got no sponginess at all when we applied the brakes for the first time.
After the tires are back on, it's easy to see why you can only fit this system into a 16" wheel: there's plenty of room for the rotor, and very, very little for the caliper. Here's the finished look through the wheel.
By this time it was right after 5:00...the total installation took less than a day. It's really no more than a half-day job but since we took well over three hundred pictures and a long lunch the time drug out a bit further than was truly needed. Even with all the pauses and narrowly-avoided beard-carnage, the end result was so entirely worth the effort: after backing Greta of the garage out we went on a quick test drive and could hardly believe what we were experiencing. Before you even ask: yes, the details and analysis are forthcoming. To whet your appetite, let's just say that I'm going to do everything possible to show you just how well this system works.