RedLS1GTO

First off... thanks to all of you guys who have answered my dozen or so questions over the last month or so about brakes, especially Randy at DRM

After more shopping around than I care to remember I finally decided to get a set of Wilwood Superlite 6-pistons for the front, and go with Wilwood Polymatrix pads and EBC rotors on the rear (rather than replacing the calipers as well) There was a lot of question about whether they would fit and pretty much everybody said "no." Hell, even John at CCW said he didn't think they would.

BUT, me being who I am decided that I was going to find out for myself. I did a LOT of measuring, and even made a 1:1 scale cardboard cutout of the assembly to fit inside of the wheel. Everything seemed to fit so why not try?!

I haven't had a chance to try them out yet, but everything fit together perfectly and the install was amazingly simple. My biggest glitch was that Wilwood recommends not using OEM lines. I had steel braided lines to my stock calipers and thought I would be ok. Turns out that the fittings are completely different (which makes sense). A few calls to Wilwood and I had a set of lines on the way. I still have to change the fluid in the whole system, give them a good bleeding, and finish working on how to keep them cool. Can't wait to get it out on the track again!

The old...



The NEW!!











Working on getting the calipers aligned properly



VOILA!!



Plenty of clearance all around (more than it looks like in this pic)

BrianCunningham

Nice setup, that's probably what I'll be stepping up to.

ErnieN85

Your going to love them!

Mojave

Is that the kit from Wilwood? Do you have a part number? Did you get those from Wilwood or someone else?

RedLS1GTO

It is the kit from Wilwood. The part number is 140-8337. I got them from someone else who is a friend of mine and got me an unbeatable price. However, I looked around a LOT and by far the best place to go is either Summit Racing or DRM (vendor). It is a little cheaper from Summit, but the guys at DRM really know their stuff and can actually provide support once you buy it. If I hadn't had an awesome deal come through, I was going with DRM.

You will also need to get a brake line kit to get it all to work since the fittings are different. It is 220-8338. I got that straight from Wilwood because Summit and Jegs both had a 3 week backorder.

WBHighwind

How much are replacement rings for those rotor hats?

longdaddy

be careful how you route wilwood lines. i angled it so the black plastic sleeve was touching the bracket, it melted on the second track day and I now have liquid plastic splatter everywhere on the back side of the caliper the other side was not angled as much - but as a result it was rubbing against the wheel at full lock.

by the way, the fitting on the end of the 90 degree elbow that comes with superlites kit will fit stock C5 lines, I am thinking about using the goodridge c5 stock replacement lines for additional metal elbow to prevent contact between the lines and the caliper. will post pics of the setup in another thread in a bit. not sure how much of a problem this would be on a C4 - but definitely check the lines with suspension loaded and the wheel fully turned either way. it took me several tries, stripped fitting, and some zip tie redneck engineering to get this right.

RedLS1GTO

Rings are somewhere around $300 for a pair depending on where you look. Hopefully the longer life will make that part a wash as far as price goes. We'll have to see.

I have looked at it pretty thoroughly and I don't see any issues with the Wilwood line kit on the C4. There is no contact of either the caliper itself or the wheel with any wheel position.

lbs90ZR

Those new brakes sure look good.

Actually the old calipers and bracket would upgrade me a little if you still have them and want to sell them?

Kubs

Looks great! How much room do you have on those studs to move the caliper out if you decide to use a larger rotor? Down the road I was looking at using the 13.06 GT48 rotor instead of the 12.88 in that kit. Could I put some washers on the bracket studs and move the caliper out or is there not enough room?

STEVEN13

Looks nice!! I am guessing this works with your stock master cylinder? How does pedal feel? Do you think these would fit 17" Z06 rims and 17" ZR1C4 rims? Thanks for posting and let us know how you like them.

Steve

RedLS1GTO

There is a guy that I work with that said he wants them for his... if he doesn't come through in the next day or so I will let you know. I went through them this weekend and cleaned/painted them so they look like new again. They really have next to zero use. The car only has about 12,000 miles on it total and those weren't on it for much of that. I also have the stainless line kit for them if you are interested since I went with the new one from Wilwood.

There is a lot of room to move them out on the studs actually. I don't know how far you could go before it started affecting the strength though. If you look at the pics of the bracket you can see that the caliper actually slides over the larger diameter section just past the stud. I'm guessing anything farther than that would be bad.

I haven't even had the chance to get the fluid changed and bleed them yet so I can't tell you about the pedal. Wilwood says that the stock m/c will work just fine. If I end up with something larger on the rear I'm planning on a dual m/c setup. I'll keep you posted on that.

As for the other wheels, I can't say for sure. I'm running a Grand Sport offset and I have about 7/8" clearance. Somebody could do the math I'm sure.

BrianCunningham

Sounds perfect for me since my race wheels are 18in

STEVEN13

Thanks for the response!

John Shiels

They would be nice on my GS but I have not driven it in three years.

96CollectorSport

I would really be interested in how the pedal feels, I know when I installed the SL6 kits on C5's in the past the pedal got a little long. Just a nature of the kit, so I'm interested to see if this is the same on the C4 kit as well.

BrianCunningham

Make that definitely in my future.

I kept hearing this noise from the front of my car, same corner I just did brake rotors pads and a beaing on.

1st thing I did was check the caliper bracket bolts, all torqued down.

The caliper itself is bouncing around in the mount.
So the guide rails are worn out!

0Todd TCE

I suspect part of the reason for questioning fit here is that the C4 kit uses a 1.10" wide rotor and not the 1.25" wide rotor of the later kits. This change in rotor width allows the fit to be packaged further 'inboard' than would be possible with the 1.25 and related wider caliper thus making wheel clearance to the good.

Anyone looking to move this direction let me know. No need to pay Summit prices when you have a dealer here with 17yrs experience! lol

rfn026

My concern with this arrangement is that Wilwood says to discard the rotor at 0.006 of wear. At $189.00 per ring that gets expensive real fast.

The one question I keep coming back to is "What are the advantages of a 2-piece brake rotor. Especially if the replacement cost is so high."

Richard Newton

0Todd TCE

Sure you don't mean .060" of wear? As a rule of thumb I favor 10% reduction as minimal thickness. Less wear than that for track use apps of course. This takes the common 1.10 rotor down to about 1.00 which is the same spec it's used for on other apps, or for example a .810 rotor is also the same casting as a .750 part. (net .730 min)

Some of that depends upon the casting used though as lighter weight castings have wider air gaps and thus thinner rotor cheeks.

Advantages are primarily light weight and some improvements in cooling depending upon what it replaced. Also if it's larger in dia than the oe part the leverage value in the final torque equation is increased thus more "power". *although not really as less clamping is then required also...