oldmansan

I recently installed StopTech ST-40 calipers and 14” two-piece slotted rotors on the front and rear of my base C6. I also installed a set Quantum Motorsports spindle ducts, hose and Z06 brake ducts.

First, jack up the car and put it on stands. I use the preferred jacking points and use jack stands and a jack.

You need to remove the stock calipers, hoses and rotors. Don’t forget the rotors have little retaining clips on one or two studs. Remove those and trash them. Cap the hardlines and be careful with the fittings on the hardlines (more on that later).

On to the spindle ducts and Z06 ducts. For a C6 you need to enlarge the hole in the fender well liner. You need to remove the lower plastic retainers on the section that holds the C6 brake duct. Remove the ones going up and down and right to left so you can get your hand behind the fender well liner. Contrary to the instructions, the stock brake duct is fastened to the bumper inlet with a single plastic retaining piece. You need to remove it and it’s easiest to do it from inside the fender liner. Pull the stock duct out from behind the fender liner.





Quantum will provide you with a template whether you buy their brake duct or just their spindle duct kit. The template is for the left (driver’s) side. Cut out the template, then trace around it on a piece of cardboard and use that for a template. Label the top of the cardboard “left” and flip it over and lable that side “right”. I found that the template needed a little more cutting at the bottom to keep the duct from hitting up against the fender liner. Quantum’s brake duct might be different.

Mark the fender liner and use your tool of choice to enlarge the hole. I used a dremel with a cutting wheel and then smoothed it out. Once the hole is big enough put the brake duct through the hole and fit it to the bumper inlet. You can stick one hand up in the inlet and feel how the brake duct is fitting with the other hand behind the fender liner. Once you’re satisfied you need to use a punch to mark the spot where you’ll put a hole and fastener into the metal fenderwall to fasten the brake duct. But first you need to secure the hose to the brake duct.

Quantum recommends cutting the Z06 brake ducts to facilitate the larger hose, but I think the flattened section is probably the limiting factor in airflow and just left mine alone. I used 8 zipties instead of 4 because I’m like that. Punch two holes per ziptie in the brake duct and the hose to cinch the hose to the brake ducts. Make sure you’re securing the duct hose via one of the bands, not just the material.





Now you can install the brake ducts. I drilled a pilot hole and used a hex head self-tapping thread cutter screw. Once it is secured the duct isn’t going anywhere.



Next you want cut the metal piece on the front hub that holds a brake sensor for relocation of the sensor. The instructions have a good picture and diagram of where to cut. Instead of using zip ties to relocate the sensor to the back side I took the metal piece that was cut off and trimmed it with aviation shears, drilled a hole in it and mounted it with the top 3/8” bold Quantum supplies for their spindle duct. I like this because it clips on like stock, is suspended in the air and keeps the lines from going anywhere.




I can’t speak for other brakes, but the StopTech brakes necessitate modifying the Quantum spindle ducts. I think I know why. StopTech requires you to grind down a few millimeters of the spindle hub. I think their rotors sit a bit farther inward than others. This being the case the spindle duct opening will hit up against the back of the rotor. You’ll have to file away a few millimeters of aluminum to solve this. This shouldn’t be an issue unless you have StopTechs.




You’ll need to trim the excess hose. I recommend turning the steering wheel to full lock, where the hose will be stretched the most and making the shortest hose possible. Remember, you’re at full suspension droop with the car up in the air and you’re never going to be at full lock and full loop. Also, when you connect the hose to the spindle duct, you have to ensure that the coil that reinforces the hose isn’t protruding farther than the spindle duct or it might rub.

Now it got interesting. I did the rears first and the only issue I had was with one of the fittings. I had to file the outer edge a bit before the threads on one to get it to thread. Installed the rears, bled them and went for a little test drive and no issues. Next were the fronts and I started with the right front. The fitting was tight just to remove and I suspect it was overtorqued as other’s have reported. After I hooked up the caliper and line the fitting leaked. Not good. Bottom line was I had to cut the line and put on a new fitting. The details and a good picture of the brake components are here;

http://forums.corvetteforum.com/sout...formation.html

While I was waiting for the fitting I did the left front corner and no problems. The finished product.






Here are weights of the base C6 and StopTech brakes. C6 base front brakes total 60.4lbs or 30.2lbs per corner. C6 base rear brakes total 42lbs or 21lbs per corner. StopTech front brakes total 59.2lbs or 29.6lbs per corner. The Quantum spindle ducts, hose and Z06 brakes are 2lbs per corner. StopTech rear brakes total 62lbs or 31lbs per corner. So overall I picked up almost 23lbs, almost all of it in the rear. Bear in mind I went from 325X32 to 355X32 for the front rotors and 305X26 to 355X32 for the rear rotors.

I drove the car on a Corvette regional run today and the brakes feel great, but I haven’t bedded the pads yet. I’ll try to bed the pads in the morning if I can find a police-free area.

I’d like to thank Matt Weiss from StopTech and Dave Zeckhausen from Zeckhausen Racing for their help. My “brand new, factory-sealed, in the box” brake kit wasn’t in fact as advertised. It had some issues that Matt and Dave helped me to resolve. Thanks guys.

San

nwc6

Nice write up.. Those are just badazzed..
Be prepared for a brake dust bonanza.. I installed just the Z06 ducts this spring and man do fronts kick the dust out now. My gumby rims will turn almost brown on a 40 mile twisty run...

oldmansan

I guessing bedding them in will produce a fair amount of dust.

San

66yellowstingray

Nice rims! What are those? Lightweight?

oldmansan

Yeah. CCW C10s. One-piece forged. 18X10.5 in the front and 18X13 in the rear. They're done in what's called Hyper Black. In low-light they look black or nearly black. In the sun they look like a charcoal grey or silver metallic.



San

C6400hp

Looks great San, glad to see you finally got it all together. Let us know your impressions after some "spirited" use.

oldmansan

Will do. They actually got some spirited use today, enough to slightly bed the pads, but not properly.

San

aTX427

Is it typical to run the same size calipers and rotors in the front and rear? i would think that would throw off the bias front to rear. How about adding 20lbs of unsprung weight to the rear - seems like a lot. Not trying to be an azz, just have not spent a whole lot of itme researching brake systems.

oldmansan

The front and rear calipers utilize different sized pistons to properly proportion the clamping force and braking distribution. Brembo uses a slightly smaller rear rotor but uses the same rear setup whether you use the 14" or 15" fronts. Stoptech does the same thing in that they offer one size rear rotor. It's all in the design of the front piston sizes.
I would have considered going with a front kit only and moving the fronts to the rear, as many here have done but the kit I bought was a four-wheel kit.

The unsprung weight added with the brakes doesn't take into account the weight I saved with the CCW wheels, Toyo tires and lugs. Even with the spindle ducts I gained 1.4 lbs per front corner of unsprung weight and 5 pounds per rear corner of unsprung weight. But you have to look at all the details to gain some perspective.

Stock tires were 245/18 front and 285/19 rear. Stock wheels were 18X8.5 front and 19X10 rear. Toyo tires are 295/18 front and 335/19 rear. CCW wheels are 18X10.5 front and 18X13 rear. Rotor sizes increased from 325X32 to 355X32 for the front rotors and 305X26 to 355X32 for the rear rotors.

Braking is directly related to the contact patch and stickiness of your tires. The big brakes and ducts are utilized to withstand multiple stops without fade and to increase overall thermal capacity. If you've ever gone to brake at the end of a long straightaway at the track just to find your pedal goes to the floor you can appreciate this.

Everything has a cost, and the 12.8 pounds pounds of total unsprung weight added is very small when compared to the increased handling and braking capabilities. I've actually reduced the weight of my car by 7 pounds with all of the upgrades. I still have suspension and sway bars to do which will take more weight off and I haven't really gotten serious about weight reduction yet.

San

aTX427

Thanks for the detailed explaination. Heard nothing but good things about StopTech. I would really like a set, but since I don't track my car, it would just be expensive jewlery.

oldmansan

No problem. It really all depends on what you're going to do with the car. You knew when you added a supercharger you'd be adding weight to the car but the overall outcome was more important to you. You obviously saved some weight with other modifcations as stock parts are usually heavy. Freakin outrageous numbers by the way.

I knew as small as the stock rear rotors and calipers were I'd probably take a small hit on weight with the brake upgrade there. I'll make up the overall weight somewhere else, but unsprung weight is king and there aren't a lot of options left to reduce unsprung weight unless I want to get rid of the rear parking brake, which I can't justify. Brake ducts are almost a no-brainer if you're going to be doing agressive braking and the weight there is neglibable.

San

aTX427

Yup, there is always give and take. Not sure what Toyo's you are running. I have A6's all around, which are much lighter (and stickier) than the pilot sports I had previously.

oldmansan

Sorry, Toyo R888s.

San

NYC6

About time! You should have went with Z06 Brakes.



Good write up. They look great, especially like the duct work. Z06 ducts and spindle kit are on my short list. Looking forward to your road test report. Do you track the car? Now all you have to do is add some more gittyup now you have that extra whoah. Enjoy

LTC Z06

Nice, I'll be doing the same thing soon, and with CCW C140s also. I like your set up, the ST-4 caliper is really all you need for a C6 the only reason I have the ST-6 for the fronts is I found a used kit here for only $2,800.

mvcrash

Great job, looks nice. did you install stainless steel brake lines? Removing the rubber from the system does a lot for the feel and function of the brakes.

YLOFEVR

San--I'm about 5 clicks away from doing a big brake job myself. I like the bling factor of crossdrilling, but I don't track the car. Quarter mile runs are probably in the future after the mods I want finally come together. Some of the verbiage you use comes straight out of Car Tech "High-Performance Brake Systems"--I read it also and it really is educational. Great write-up and a nice job--congrats! Please keep me posted on you observations and experience with the Stop Tech--It's a great system and designed well.

oldmansan

I've never read Car Tech "High-Performance Brake Systems". Everything I've posted is just my own opinion on the purpose of big brakes and ducting. If you're only going to drag race, you don't need a big brake kit. It really won't make a difference for one or two stops but rather multiple stops where the thermal capacity of the stock system is exceeded causing the brakes to fade and/or fail (boiled fluid, etc).

San

oldmansan

Yes. Stainless lines came with the kit. I actually have a spare set of front lines.

San

oldmansan

I remember that deal you got. I considered selling the ST-40 fronts to go with the ST-60 fronts but even StopTech said there would be no performance advantage. The ST-60s do have a larger pad so they will last longer if you're doing really long track sessions. The pads are a bit pricier and of course the pads and caliper are heavier do to the increased size. I couldn't justify the additional cost and decided to stay with the ST-40s.

I went with the CCW C10s as they are slightly lighter and a little easier to clean than the 140s. I also prefer the almost symmetrical design. Either wheel is a great choice.

San