Has anybody installed AP Racing brakes?

[ChipBeck]

Stillen Performance in California showed us a trick looking AP Racing six piston big brake kit that utilized two piece cross-drilled and slotted rotors. These are similar to/or the same as, those used on Stillen's Ford GT race car. The factory GT brakes are four piston units. They claim that these brakes "provide a huge improvement in pedal steel and stiffness." Has anybody installed these and do you like them? This is a fairly pricey mod at over $7,000 front and rear combined so I would like to talk to somebody who has already done it before I make this purchase. Anybody?

Chip

 

[nota4re]

I believe our friend HeritageBruce just installed these brakes.

 

[Ed Sims]

stock GT Brembos

Has anyone found the fault of the stock/OEM brake system? I'm not racing but for the 700 miles of road race track I've done with my GT the stock system in awesome. Way better than the stock 6-piston system on the Z06 (which most replace with a 4-piston mono block system). With sessions that usually don't go over 30 mins I feel the stock system would be fine for mere mortals.

Ed

 

[Ed Sims]

one brake system mod

I did forget that I am running the Ford SVT floating 2 piece brake rotors. I did it for the unsrung weight advantage & the coolness factor. The brakes worked as well with the stock rotors.

Ed

 

[roketman]

Ed,
What are you using for brake fluid? I cooked mine with stock pads at a drivers ed.

 

[cobrar1339]

I have not swapped the fluid in the GT yet. But I have some experience with fluids in other cars and most recently a C5 Z06. With ABS I like the Motul RBF 600 factory line. I would Stay away from ATE for this application. The Castrol fluid is expensive and has some drawbacks in the GM system as well. There are lots of guys running C5's in open track and T1. The Motul is the fluid of choice for them and what I plan to run in the GT come track day.

Also note that the fluid in many of our cars is a few years old. Even a flush of the current fluid should offer significant benefits. I do a caliper bleed and mini flush every other track event in the Z. I do a full system flush of the ABS every second or third event using the GM tech2 scan tool that cycles the ABS for a programed flush. Some tracks here are easy on brakes, so I may skip one now and then. Others take far more abuse.

There are lots of reports that brakes are fine and brakes are weak. I doubt anyone is wrong, just different tracks, horsepower and tires. You should have little problem at any track with fresh fluid and 30 min sessions. The six piston calipers will do little for fluid temps over the 4 pots, maybe even worse like ED mentioned.

The reason for more pistons is to help the pad wear more evenly and distribute clamping force. One surefire way to tell is to look at your pads after a track weekend. If the pad has worn in a way that it is tapered by a significant amount. Then you know there is room for improvement. If it has not, your gains will be minimal or nil IMO. Most of the time the tapered end will be at the front of the car. That little bit of taper will become extra pedal travel. Sometimes this is the issue, not the fluid.

The big brake combos I have used ( Alcon, Brembo, Stoptech ) are more about pedal feel than actual stopping distance when swapping from something like we have. When swapping form a production car with a PBR system it can be meaningful, the taper starts to go away and the pedal stays higher and harder. IMO stickier tires will reap the most benefit fast, next is wider stickier. Pedal feel will change quite a bit based on the pad material as well. The initial bite of one compound vs. the other can be huge. The trade off is noise, dust and rotor wear. One session with race pads in my Z and the wheels look like I had them powder coated in a graphite color.

 

[Ed Sims]

brake fluid

Rocketman - I am using the Performance Friction Dot 3 brake fluid currently. I get a good deal on it price wise but feel there are many other fluids that will work equally as well. My GT has an awesome firm pedal feel even after repeated braking at 140 mph. I can detect some fade at the end of a 30 min session though but not too bad.

Ed

 

[BlackICE]

I just bleed the system using Valvoline SynPower High Performance Synthetic fluid. The price is right at about $7/qt and the dry boiling point of 500F is much better than the standard stuff, but not as good as racing DOT3. However the wet boiling point of the stuff is 343F which may be better than racing DOT3. I will see how well it works on Friday at Thunderhill.

I the past with an old Vette I used the cheapo Prestone stuff and never had a problem, but I always bleed the entire system within 1 week of a track event.



http://www.valvoline.com/products/Valvoline Synpower High Performance Brake Fluid.pdf

 

[Indy GT]

Chip, I am kinda with Ed on this one. For mere mortals IMO the stock Brembos do a very good job in the braking department. Now for the 2% of owners who routinely track or run their car extremely hard maybe a justification can be made. Or the owners just want something different to be different.
While we were a Stillen this August, Mark McGowan commented on the brake testing they performed on the GT while under development. It was pretty impressive and garnered the "excellent" rating the team was shooting for. (One ABS stop from 80% Vmax (164mph) immediately followed by full accel to 60mph with another ABS stop repeated 9 additional times--without any fade). Last two stops were the shortest recorded.
Sure everything is a compromise and there are undoubtedly compromises in our system for rotor wear, brake dust, noise, etc. but it appears the team has given most of us owners a pretty good overall system....IMO

 

[ChipBeck]

The brake down.

Chip, I am kinda with Ed on this one. For mere mortals IMO the stock Brembos do a very good job in the braking department. Now for the 2% of owners who routinely track or run their car extremely hard maybe a justification can be made. Or the owners just want something different to be different.
While we were a Stillen this August, Mark McGowan commented on the brake testing they performed on the GT while under development. It was pretty impressive and garnered the "excellent" rating the team was shooting for. (One ABS stop from 80% Vmax (164mph) immediately followed by full accel to 60mph with another ABS stop repeated 9 additional times--without any fade). Last two stops were the shortest recorded.
Sure everything is a compromise and there are undoubtedly compromises in our system for rotor wear, brake dust, noise, etc. but it appears the team has given most of us owners a pretty good overall system....IMO

Great information. As I seldom track my car this thread has convinced me to leave well enough alone in the brake department. I'm still going to buy those trick Penske shocks from A&P though. :biggrin

Chip

 

[dbk]

The AP Racing Brakes would make a huge difference if you were a track rat. When Camilo got out of Steve Millen's car the first thing he said to me was a big "Holy Shit" on the braking.

For the street, the stock brakes are pretty good, and if you plan to track, as Ed mentioned the lighter SVT rotors will make a nice difference. They performed extremely well in a recent test I was at. If you'd like better braking without the huge cost, I'd go that way. If you just want the best period, I'd go with the AP's.

 

[cobrar1339]

Kyle, what pads are you running with the AP set-up?.

 

[Ripper 02]

Another Pad Question??

What pads are recommended with the SVT Rotors??

Stock??

 

[cobrar1339]

http://www.hawkperformance.com/motorsports/applications/gt.php

Ripper, I doubt it makes much difference as the rotor won't care either way. At that price they are likley heat treated. That allows them to wear better when an aggressive pad is used. I would think you could run any pad with them from the site above. Both the Ford and AP rotors are very good. I personally do not like drilled rotors for track specific cars. They tend to crack too easy form hole to hole. Slotted IMO is the way to go for a dedicated car and reduced rotor expense.


The site has info from Hawk on pads and compounds. A testimonial, etc. This is the New pad for Hawk. Several T1 drivers had switched to Carbotech pads a couple years ago. Just as an FYI, T1 is a very stock class. These guys must run the stock OEM calipers with factory two piston PBR's. The races are about 30 -40mins. For grins, check the track records /Times for T1 at your local track. They are on the SCCA website. You will be surprised how fast these guys get around the track in virtually a bone stock car with a cage and a few suspension mods, agressive alignment. No fancy shocks, slicks, dry sumps. Weight is about the same as stock after a cage is added. And they make around 380rwhp tuned.


Pad Exploration:
There is a significant difference in the pedal feel and intial bite from one pad to the next. I have not run the new Hawk compound yet. But have heard it is darn good. I have tried the Performance friction PF01, Hawk Blue, Porterfield and the Carbotech XP10 which I run now. I have switched around trying to find the one that feels best to me. After the PF01 I went back to Xp10's and that is where I have stayed. When I wear them out I may try the new Hawks.
Kyle mentioned we had the F40 / F50 caliper. On this you select the year, mfg....go to special caliper and pick Brembo, then F40 and it will bring up some options.

Tech Dept:
The tech departments always give you a good starting point. The weight of the car, horsepower, tires, brake temps are a few of the questions they will ask to help find a compound to start with. They may even send you some paint to put on the rotor edge to determine how hot it gets. If you can find someone that has tried a few, they are the ones to speak with. Almost all will be night and day over OEM in some aspect. At least that has been my experience over the years.

Real World Experience:
Our buddy Kyle ovbiously has some experience and a few compounds to choose from. Hope he chimes in here to narrow the search.

Empty Pockets:
If you hate brake dust it looks like these guys make a ceramic pad in your size. Just think no more brake dust when pushing it in and out of the garage.:biggrin

 

[Ed Sims]

pads

I'm running the stock pads. They work well for short sessions (20-30 min) & are friendly to the rotors. Cobra R is correct that drilled rotors aren't the best with full track pads as the rotors will eventually crack. With the stock pads I haven't had any problems other than higher pad wear than if I were using a harder compound pad. I also don't want to swap out pads after the event so I run the stockers (no squeal & good cold braking).

Ed

 

[Empty Pockets]

Empty Pockets:
If you hate brake dust it looks like these guys make a ceramic pad in your size. Just think no more brake dust when pushing it in and out of the garage.:biggrin

Aaaaaaaaaaaaah! I'm on it like white on rice...:bored :skep:bang

 

[Ripper 02]

cobrar1339

Thanks for the Post!!!

Very Useful Information!!!

I will continue to run the stock pads at present.
Just goint to order the SVT rotors and give that
combo a try for now...

 

[kmillen]

We have a few different pad options for the AP's as well as the factory Brembo's.

My personal preference is the Mintex extreme. They are a fantastic pad. They offer great performance when their cold and get better as they heat up. The most important thing to consider is what you're going to be doing with the vehicle. For a car that sees any track time, I recommend the Mintex extreme pads. For a car that is only going to be on the streets with maybe some spirited canyon/open country road driving I would recommend the Hawk HPS pads. For a car that is used for simple enjoyment, never driven hard, never really "opened up." I would probably recommend metal matrix pads.

We have another pad that is made to order. They are the ones that I recommend for cars that spend a lot of time at the track and for cars that are driven hard. We used them on the rally in our AP kit and they were incredible. Half way through the rally we decided to change pads simply to keep up with maintenance. We found that the pads were only worn about 1/2 way and probably could have completed the rest of the event. It was the ultimate testing of a braking system in our eyes. Here is a small description of what our car went through on the rally.

Fire up in the morning around 7 a.m.
Haul butt through city roads to the first stage. (pads needed to work in the cold)
Sit and wait for your turn to start.
brakes are now cold and the green flag drops. Race through a stage (ranging from 12-55 kilometers in length.)
Some stages were in pouring rain, other stages were in 85 degree temperature (not too hot but this meant that we were getting better traction and therefore using more brake getting into the corner.)

Overall it was a great test for the brakes and they performed flawlessly. We did experience a little bit of overheating (fluid boiling) with the Motul RBF 600 fluid but that was remedied by switching to the Castrol fluid. It is expensive at $85.00/bottle but that fluid is amazing. The boiling temperature is actually not that much higher than the RBF fluid but it dissipates the heat much faster.

 

[cobrar1339]

Kyle you are the man. Thanks for the data and flavors available.:thumbsup Mintex is not a real popular brand in the domestic run groups, but I have heard very good things about them from other types of cars at the tracks. Thanks again.

I can see where you would run into trouble with fluids in that kind of rally. Your sessions appear to be several hours long.

My beef with the Castrol in another C5 was that we noticed a low pedal after several hard events ( about 12). We switched pads after several flawless sessions and the pedal never came back. We chased this for a couple weeks when we got back. We flushed, maybe $500 it through the system. It never got better. Finally we decided to try the Motul fluid on a recommendation from another T1 team that had a similar issue.

When we did the flush with a tech2 purge a couple times using the Motul, we started to get a thicker version like syrup coming through. The third time was a charm and the pedal came back. About two years now without issues. While we have used the Castrol in an AS 5.0, I have been reluctant to recommend it for ABS/Stability systems since then. Kinda like trying to loosen the ketchup bottle lid. Then someone comes along and opens it up easily. I do not know if that is the case here. Lots of folks use it without issue. I do agree it worked much better in the overstressed 5.0brake system than anything else we have tried.

Thanks again for all the good info.

 

[kmillen]

A typical race day for us started at 730-8 am. and ended around 5 pm. We would run about 9 rally stages a day and on two of the days we were at proper race tracks. The entire rally lasted 6 days.

The RBF fluid from Motul is great stuff and we use it in almost every vehicle that we have in stock at the shop. The Castrol fluid is actually something that we just happened upon during the rally. One of the other teams saw that we were having problems with the fluid and offered to supply us with some of their castrol fluid.

I like the RBF fluid and it's in everything I own but we have the Castrol fluid in the GT.