Sebring27

Hi
Looking to put bbk and 18" wheels square on C5 z06 trac only car
I have been considering speedlines or tsw with either brembo or stoptech
I would ideally like to use without spacers
Any advice on bbk and wheels much appreciated!

Charley Hoyt

I can't help with the wheels... But I recently went through the BBK decision. I wanted a balanced front and rear kit but I didn't want full floating rotors. There are lots of great kits out there but I narrowed the search down to Brembo and Stoptech. Brembo's supposedly have a very slight performance edge over the Stoptechs but have considerably higher consumable cost. If I had an unlimited budget I might have gone with the brembos....but, didn't think the slight increase in potential capability was worth the higher cost.

Charley

427ZM

I've been looking at bbk's recently as well, and I really like the AP racing and Alcon kits myself. Any knocks agianst either of these kits? I know stop tech and brembo both have the lions share of bb kits, but I like the rotor technology both Alcon and AP racing use.

http://www.essexparts.com/shop/compl...rake-kits.html

http://www.alconkits.com/index.php/B...rake-Kits.html

troyguitar

Alcons are top quality for sure, they are used on a lot of 4000 lb Audi S4's and stuff like that. Only issue is reduced availability of parts since they are more rare.

Joy of 6

I've got the AP kit and TSW Nurburgring's Pads are 20 mm and inexpensive. +

Sebring27

Hi Are you running 18 x 10.5 square?
Which AP kit?
thanks !

427ZM

I'm currently running Fiske FM5's 18x10 and 19x11. Would I run into figment issues with either the alcons or the AP kit? I agree, it seems like its a big plus that AP has a bunch of pads that'll fit their calipers.

427ZM

Also, if you went completely square (C5Z wheels 18x10.5) would there be any figment issues? I'd want to go 6 piston fronts and 4 piston rears.

0SpeedFreaksUSA

Any BBK you choose will be a huge improvement over stock in terms of raw performance, consistency and running costs.

I have a few questions to help narrow things down if you don't mind answering. Do you just use the car as an HPDE car or are you racing in wheel to wheel series? If so how long are the races? How much does the car weigh and what tires will you be using?

Im currently using the Stoptech kit on the front of my car (stock rears) and my only frustration was not switching sooner. After the first season and a half I had recouped my initial investment in pad savings alone, even without ducting

I chose the Stoptech kit because I still daily drive my car and their kit is designed with street use in mind. Since your car is a track only car I would lean more towards the Essex AP Sprint kit since it should have the lowest consumables and running cost of any kit for the C5. If you are racing the car for longer than 20-30 minutes at a time on slicks then the Essex AP endurance kit may be something to consider.

http://speed-freaks.net/i-13899716-a...tte-c5-c6.html

The Brembo kit is also another option but it (like the stoptech kit) was designed primarily as a trackable street kit, where the AP system above is more of a streetable track system. Like others have mentioned the Brembo kit is more expensive plus pads and especially replacement rotors are much more expensive than other options.

Sebring27

That's great - i really appreciate you taking the time in replying.

Purely a track car - Presently for HPDE/ TT only - not sure what the future holds with regards to wheel to wheel ! Anyway have installed cage, diff, oil and tranny cooler, stripped interior and will weigh in just under 3000llbs
Will run a Nitto NT-01's, R6's or even Conti Scrubs.

I will take your advice and seriously look at the AP offering and see if they have suitable kit for 18" fronts on the C5.

Cheers !

0SpeedFreaksUSA

Thats what we're here for

For sessions less than 20-30 minutes the AP sprint kit using the CP8350 calipers and 325x32mm 70 vane rotors will work very well on your car. They will clear the barrel of 17" wheels and larger. They should also have no problem clearing the face (unless they are some deep dish wheel with a gigantic lip) To double check here is the template: http://www.essexparts.com/media/down...l_template.pdf

The kit was designed around meeting SCCA T1 rules and should comply other organizations rules as well, potentially making the jump into wheel to wheel racing less of a headache or at least freeing up a few more points for your class.

We have access to pretty much every aftermarket brand you could imagine and offer special discounts for our friends here on Corvette Forum so please feel free to PM us if you have any questions or for pricing as you get closer to pulling the trigger on something.

-Matt M.

Joy of 6

I used to run 18X10.5 square Fikse's but got a good deal on the TSW's so running 17 front and 18 rear. Either case the AP's fit just fine. I got one of the first set of AP T-1 calipers which I still have and have no reason to change. However they have ,as mentioned above, the sprint and endurance to give you a more diverse choice. I believe C6R's came with AP's. Anything other than stock will be a great improvement in stopping power and consistency lap after lap. Its just a matter of changing a sliding caliper to a fixed.

Sebring27

Thanks ! Much appreciated !

Hi Volts Z06

I've had great success with StopTech's 6 piston fronts and 4 piston rears. While I run CCW's for my normal race wheels, I do have TSW's for my rain tires and the fitment is perfect without any spacers. Also- the Speedline 10.5's do fit all the way around so they are a cheap alternative.

JRitt@essex

Hi,
Please check out our Essex Designed AP Racing Competition Big Brake Kits. Our kits are designed specifically to handle track abuse, and contain many features unavailable from other manufacturers. We have two different front kits and a rear kit, depending on your needs:

Sprint Kit- Four piston / 325x32mm discs




Endurance Kit- Six piston /355x32mm discs




Rear Kit- Four piston /340x28mm discs


Hi Guys,
I've now had 3-4 forum members message me over the past couple of weeks asking about a direct comparison to the StopTech systems currently on the market. I really appreciate that people don't want to start a mud-slinging brand vs. brand battle in my thread. That said, I'm happy to lay out the facts to those who are interested. I think it's important for people to understand what exactly they're getting when spending thousands of dollars on a brake kit. I don't see any harm in sticking to the facts/specs, and I'll try to leave out conjecture.

I was actually the sales manager at StopTech for roughly five years before taking on my current role at Essex/AP Racing. While at ST I was also involved in just about every part of the process of bringing their products to the market (production, product mgmt., component sourcing, etc.). I doubt there is anyone more uniquely qualified to compare their system to ours. Below is a comparison of the components in our kit vs. those in the StopTech setups, but this info also applies in the same manner to other high performance street big brake kits (painted calipers, aluminum pistons, dust boots, drilled discs, etc.) currently on the market.

Here's the breakdown as I see it comparing our Essex Designed AP Racing Competition Big Brake Kit vs. the StopTech six piston BBK with 14" (355x32mm) discs.

Calipers
Essex version of the AP Racing CP5060 six piston vs. StopTech ST-60 six piston

Anti-knockback springs
AP Racing has them, StopTech does not. People severely underestimate how valuable these springs are. After going through S turns, you'll have a much lower pucker factor in the next brake zone with the AKB springs installed.

Piston type
StopTech= cast aluminum
AP= machined stainless steel, domed back, ventilated
Stainless steel is far superior at keeping heat out of your brake fluid vs. aluminum. The domed back on the AP pistons adds substantial stiffness, which can be felt as a firmer pedal. The ventilation on the piston edges allows for more cooling air circulation. All of these features add up to greater heat rejection around the piston area, ultimately leading to a lower chance of brake fluid boiling and resulting fade.

Weight
StopTech ST-60 is 8.9 lbs.
Our version of the AP Racing CP5060 weighs 6.2 lbs. without pads...approximately 3 lbs. lighter per side than the StopTech ST-60.

Dust Boots
StopTech is a street caliper, and as such uses dust boots. The AP CP5060 has none. If you've ever run dust boots on the track, you'll find that they burn up and cause a big mess almost instantly. Their only value is if you're driving on winter or debris/dirty roads. As soon as they go on track they essentially lose all value.

Seals
Both calipers have quality, high temperature seals.

Pad choice/cost/size
The ST-60 and AP Racing CP5060 use the same basic shape (it was originally an AP Racing shape, implemented many years ago. The D54 radial depth version we use in the CP5060 has an additional 3 mm of surface area along the lower edge, giving a bit more pad volume vs. the D51 pads in the ST-60. Pricing on the two pad shapes is the same.

Stainless Steel hardware
Both calipers have quality stainless steel hardware.

Footprint/size
In addition to weighing much less, the CP5060 has a smaller footprint and tends to offer superior wheel fitment.

Finish
StopTech= painted. Look pretty, but will not look as good after hard use. Red turns maroon/brown, etc. Paint and powdercoat tend to color shift dramatically at track temps. If you're driving through road salt however, they will be better protected than anodized.

AP Racing= anodized. Look 'racier' (like what you see on full-blown race cars like the factory Corvette race cars below) and do not color shift nearly as much. I tell people that they go from grey to ugly grey.

Bracket
Both have high quality anodized aluminum brackets and aircraft quality hardware.

Rebuild Service
Essex offers a lifetime professional reconditioning service. For a $150/caliper you can send your calipers to Essex and have them rebuilt by the same techs who service calipers for NASCAR Sprint Cup and ALMS teams. StopTech can rebuild I believe, but I'm not sure how formalized their procedures, policies, and prices are at this time.

Discs

Design
Discs from both manufacturers are quality castings that are crack resistant and will last a long time under heavy track use. That said, the AP Racing discs are a heavy duty 72 vane internal construction, and patented J hook face slot are the #1 choice at the elite level of motorsports (NASCAR, ALMS, DTM, Super GT, etc.). The StopTech's are only a 48 vane disc with a conventional slot pattern.

Disc hats
Both have a quality design and are made from high grade, anodized aluminum. Both are optimized for weight and airflow.

Weight
Essex/AP Racing hat/disc=17.6 lbs.
StopTech hat/disc= 18.6 lbs.

When you combine the caliper and disc weights, our system weighs 4-5 lbs. less per side vs. StopTech or 10 more lbs. off the nose of the car.

Spare Disc Price
Even though the AP discs offer far more features, pricing is almost the same as StopTech's recently increased price per disc. Replacement iron prices per disc are as follows:

$359 Essex/AP Racing Sprint Kit (355x32mm)
$335 for the StopTech 355x32

Other Items

Wheel Fitment
I believe our Essex Comp kits sit inboard of the StopTech setup a bit, offering superior clearance. I'd need to check to find the specific difference.

Brake Lines
Both systems came with a high quality set of brake lines. The Spiegler lines in our setup use all stainless steel fittings made in Switzerland (assembled and tested in Ohio). The fittings on the ST lines are not quite to the same spec.

StopTech Trophy Kit
The other option to go with for a StopTech six piston on a 14" disc would be their Trophy system. The differences in that system vs. their standard setup are: Caliper weighs about a pound less than the standard ST-60 roughly 7.9 lbs...it has more material removed during the machining process, caliper is anodized, available with no dust boots, washers can be flipped on discs to offer more float, disc hats are anodized. AKB springs are available at an additional charge.

Overall Kit Prices
StopTech ST-60 Trophy= $4145
Essex Designed AP Racing Competition Big Brake Kit= $3,599
StopTech ST-60 BBK= $2795

Our complete kit pricing falls between the two StopTech kits with similar sized components.

Racing Pedigree and Brand Equity
While I'm far from a brand snob, I'd say it's safe to say that AP Racing gets the nod in terms of brand equity, racing heritage, and pedigree. StopTech has had good success in the lower ranks of racing (World Challenge, Grand Am, etc.), but AP dominates at the elite level. Virtually all of the factory BMW race cars use AP Racing (as noted earlier in this thread), DTM, etc. Not to mention AP dominates many of the 'money-no-object' markets when teams have a brake choice (non-spec) such as NASCAR Sprint Cup, Super GT, ALMS etc. (which btw are extraordinarily tough on brakes, even though they're typically going in a circle!).

Which Kit to Choose?
Compared to the ST Trophy kit, I'd call it a no-contest. The Trophy Kits are modified street components designed to work better on track. They have more 'race-like' features, but they are still limited in their capacity by the aluminum pistons, a low disc vane count, and heavier weight vs. our purpose built race caliper and disc. The Trophy base price is over $500 more than our kit, and the specification on the components aren't as high as they are in our kit. As such, I don't expect the components will last quite as long at track temperature vs. the ones in our kit (pads, discs, etc.). I believe our system is a significantly better value.

While our system is a bit more expensive than the standard StopTech ST-60 kit, you're getting a lot more technology for your money. If you peruse the list above, you'll see that every component in our kit meets or exceeds their specification, and is more closely aligned with professional-level race components. That is intentional. When you factor in the fact that the higher specification components will need fewer replacements, the running costs over a year or two will balance out quickly, essentially negating the initial price difference. You'll also be saving about 4-5 lbs. unsprung weight per front corner with our kit!

Summary
Ultimately both companies make a great product. I had an ST-60/ST-40 14" BBK on my Z06 while I worked at StopTech (and an ST-40 kit on my 350Z). Both were solid products made by good people. I'm also still friends with a number of their employees (since I hired and trained most of their current sales staff). When we put our Essex Competition Kits together however, I tried to look at every piece of the StopTech system and produce something that eclipsed its performance, all while keeping the costs at a level that the average enthusiast could afford. My past employment there put me in a perfect position to accomplish this task, and I believe we have succeeded...more technology borrowed from pro racing, higher specification, lower running costs, better fitment, etc. I believe what we're doing is taking things to the next level for the average club racer, HPDE student, and autoX'r, and giving them access to previously unobtainable technology and performance.

Finally, notice any commonalities behind the wheels on the cars below? The C5R, C6R, C7R and Corvette Daytona Prototypes have all run/are running AP Racing brakes for a reason. We are using technology from those programs and bringing them to the average enthusiast. It's rather tough to argue with the success these cars have seen on the track using AP Racing brakes.




Action Express Corvette Daytona Prototype

troyguitar

JRitt or anyone else: How do you address brake bias with all these different front and rear brakes?

The car (C5Z in my case) feels kind of like it has a lot of front brake already stock, will adding a sprint kit vs endurance kit affect this either way? What about the rear kit either by itself or with either of the front kits?

spazegun2213

most, if not all, aftermarket BBK's should not address bias at all. The OEM Master cylinder is fixed and thus most BBK's just add pistons, but dont change the overall piston area. Changing the piston sizes would require you to ditch the OEM master cylinder and go with something different. I'm sure there is a better way of explaining this, and I'm not a brake engineer.

That being said, a great way to adjust bias is with the pads. I run DTC70's up front and DTC60's in the rear. I dont need/want the bite of the 70's in the rear.

Hi Volts Z06

When you purchase a BBK from a company like Brembo or Stoptech, they carefully match the fronts to rears. If you are going to be doing real racing, as opposed to street driving with occasion HDPE you should really go for both fronts and backs. Regardless- on the later C5's with ABS, the ABS module handles the bias therefore you don't need to worry about anything. You can fine tune with pad selection and typically you always want to run a less aggressive pad in the rear.

troyguitar

From what I understand the internal pressure difference between the front and rear is more or less fixed as you guys said, so it makes sense that piston area would be a factor - but shouldn't rotor size matter as well?

We're talking about applying torque to a disc, so even if the total piston area is the same as stock on a big 6-piston kit as the stock calipers, there will be more torque applied with a larger rotor (same force, larger radius) thus altering the brake bias further toward the front.

Sebring27

Many thanks - Much appreciated !