C5/C4 Brake Combination
#1
Burning Brakes
Thread Starter
C5/C4 Brake Combination
Long story short - I just learned today that the C4 I bought has C5 brakes up front, but stock C4 brakes out back. My original plan was to use C5Z pads since I thought it had C5 calipers front and rear. They obviously don't fit on the rear and neither do the rotors.
So I am looking for pads to run on the rear either with C5Z pads on the front or some combo that will work front and rear. I am just on street tires.
I am guessing these rotors will work, but I wanted to see if there was anything else out there before buying.
http://www.napaonline.com/Search/Det...+50012+2012030
So I am looking for pads to run on the rear either with C5Z pads on the front or some combo that will work front and rear. I am just on street tires.
I am guessing these rotors will work, but I wanted to see if there was anything else out there before buying.
http://www.napaonline.com/Search/Det...+50012+2012030
#2
Le Mans Master
Yeah, the C5 rears won't work due to the different e-brake configuration. There's not much power to the rear so the cheap napa rotors are what I was told to use. Good luck.
#3
Tech Contributor
Member Since: Oct 1999
Location: Charlotte, NC (formerly Endicott, NY)
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Napa Ultra Premium Rotors are the ones to use. Use Hawk HP+ or HP pads front and rear.
Bill
Bill
#4
Melting Slicks
I would get something a little more aggressive friction wise in the rear; the front C5 brakes pushed the bias a little more to the front and you need to counteract that. What do you plan to do with the car, track events?
#5
Burning Brakes
Thread Starter
HPDE at Road Atlanta in 2 weeks. I really wanted to work on braking for the weekend. I was planning on switching to XP8s after that weekend since I was going to be putting on new NT01s. I could go ahead and buy the pads and put them on if it won't cause any problems with 300 treadwear tires.
Last edited by The Panther; 03-01-2010 at 09:17 PM.
#6
Le Mans Master
Put them on, I keep my xp8's on the rear between events.If you have a bias spring you may want to go up to xp10
I'll see you at Road Atl!
I'll see you at Road Atl!
#7
Melting Slicks
I really tend to favor racing pads and just swap them out for street pads when you get home, rather than use OEM C5Z pads. You will get 17 different opinions on this, but if it were me and I didn't have to pay the bill; I would get Raybestos ST41's up front and St43's in the rear. It is the best combo I have personally ever used on my C4. I got them from Porterfield: http://www.porterfield-brakes.com/
#8
Melting Slicks
I have been running Carbotech XP8 up front and stock replacements in the rear on my 85 with C5 fronts and C4 rears. I found that slowing from about 135 on street tires to a slowish 2 second gear turn is about all they can stand in a full weight C4. Had a very close call trying to bring it down from 155.
I am not sure what the XP8 equates to from other companies but hopefully this will give you an idea what sort of compound might work for you.
This is in HPDE 1 so probably not what one would consider "threshhold" braking.
I will move to XP10 fr and XP 8 rear next time out and add some cooling.
I am not sure what the XP8 equates to from other companies but hopefully this will give you an idea what sort of compound might work for you.
This is in HPDE 1 so probably not what one would consider "threshhold" braking.
I will move to XP10 fr and XP 8 rear next time out and add some cooling.
#9
Burning Brakes
I run C5 PFC 01 compound up front and Performance Friction Z-Rated C4 pads on the rear. The front I have Brembo rotors and the rear are just NAPA rotors. I run slicks but I have ran the 01 Compound on street tires and it worked ok...you just have to concentrate on threshold braking more. I then put Z rated pads on the C5 calipers for the street after the track day is over but I leave the rears the same all the time. I do not have a bias spring but it seems to work fine for me...just have to keep it straight while HARD on the brakes otherwise the back will try to come around the front when I am going from 120 to about 45 into turn 3 at Brainerd,MN.
#10
Team Owner
Do you know if a brake bias spring was installed at the time of the conversion? That spring from Doug Rippie Motorsports will help with front to rear pressure bias. Without their spring you may see lots of ABS operation at medium-hard brake application. The spring will also remove the increased nose dive from the better braking. Cost is about $20 shipped. The spring made a tremendous difference when I did my C5 front brake upgrade on my 87.
The C5 Z06 pads are in between the Hawk HPS and the HP+ in terms of compound. There is really little to gain from a C5 rear brake setup on the C4 as the rotor diameter is about the same and the pad size is about the same. My car is ready for rear pads and I'll be using HP+ pads in the rear with the Z06 already in front. I have done one track day with HPS pads out back, and they did show lots of wear after the upgrade.
The C5 Z06 pads are in between the Hawk HPS and the HP+ in terms of compound. There is really little to gain from a C5 rear brake setup on the C4 as the rotor diameter is about the same and the pad size is about the same. My car is ready for rear pads and I'll be using HP+ pads in the rear with the Z06 already in front. I have done one track day with HPS pads out back, and they did show lots of wear after the upgrade.
#12
Burning Brakes
Thread Starter
Thanks for the info. I am going to look into the spring since I am guessing it is not on the car. I ordered Carbotech XP10/8 this morning, so I can get them in time to put them on.
#13
Melting Slicks
Did the folks at Carbotech talk to you about your driving level and car?
Also, I have the bias spring and it is definitely worth doing. It's pretty straight forward expect getting the circlip back in was a real bummer.
Also, I have the bias spring and it is definitely worth doing. It's pretty straight forward expect getting the circlip back in was a real bummer.
#14
Burning Brakes
Thread Starter
The crappiness of my driving is surpassed only by the crappiness of my car.
I am picking up some other less expensive rear pads so I can try out some different combinations. It seems like a lot of it is trial and error until you find something you like.
I am picking up some other less expensive rear pads so I can try out some different combinations. It seems like a lot of it is trial and error until you find something you like.
#15
Melting Slicks
I resemble that.
#16
Race Director
I tried some different pad compounds for the rear on my track car. For the record I have C5 calipers in front (it doesn't matter, pad torque matters more) and rear C4 calipers, like you. I do have the DRM bias spring installed. I was leery of having to high of a torque pad in the rear. I tried PFC Z. Those I felt like the rear did nothing, same for HPS. I've got Carbotech AX6 in there now and they match up nice with high torque pads in the front. I think the XP10/8 combo is a good choice but better suited to stickier tires.