sothpaw2

Thinking for this season I'd like to take a crack at making my longish pedal issues go away on hard-on-brakes courses. Already have cooling ducts and SS brake lines and race (wil H) pads. Also I lub the guide pins before every event & also do a lot of cool down after a session. I still get some longish pedal by the end of the day and would prefer consistency throughout without having to bleed brakes between sessions.

So if I want less heat in the brake fluid and also to prevent caliper spread (isn't that from heat too?), have you guys who have tried them found the Ti pad spacers/shims more effective or are the SS pistons better? I don't see how the SS piston would really help with caliper spread or to protect the piston seal...seems like the Ti shims make more sense.

I did a search on the Ti shims but there is surprising little chatter...at least 1-2 folks liked them.

Opinions?

Thanks

Andy

Bill Dearborn

If you are getting taper along the length of the pads then the brake fluid isn't the cause of your long pedal. In my experience with the C5 front caliper the long pedal was always caused by pad taper. The pads on the left side of the car tapered one way and the pads on the other side tapered the opposite way. My impression has been the taper was caused by a mechanical issue with the caliper moving on its guide pins Vs a heat issue. To counteract the taper you need to flip the pads from one side of the car to the other after so many sessions. That way you can keep the pedal up. I doubt your brake bleeding did any good bringing the pedal up. First time I experienced the taper issue was when I took my 97 to Watkins Glen with 2200 miles on the clock. After two sessions the pedal was close to the floor. Myself and another guy spent a lot of time bleeding the brakes to no avail. Two days later the dealer replaced the badly tapered pads under warranty and the brake pedal was back where it was supposed to be. They didn't bleed the brakes just replaced the pads.

Bill

geerookie

This also has been my experience in regards to a long pedal.

But if you are worried about heat then I would do both SS pistons and Ti pads. I did it and ran ATE Blue/Gold and never had a problem.
As far as spreading the calipers, neither of these things will reduce that. It is a result of the heat from the disc/rotor radiating into the caliper and then applying pressure to the brake pedal. The only way to have a chance at slowing the spread down is to switch to C6 (not Z06) calipers and add more cooling to the caliper itself.

spdislife

[QUOTE=geerookie;1576771340The only way to have a chance at slowing the spread down is to switch to C6 (not Z06) calipers and add more cooling to the caliper itself.[/QUOTE]

Is there anything else beside the Ti shims and SS pistons to assist in caliper cooling?

drivinhard

the SS pistons would be better than the Ti shims (in terms of keeping heat out of the fluid)

John Shiels

mica shims and ss pistons.

sothpaw2

Bill,

You are right on with the flipping of the pads as they taper--I do that too. Last year I remember starting with brand new pads for a day at Summit (which I find is much harder on brakes then VIR). By day's end the pedal had sank quite a bit. It was not near the floor but I guess I am looking for consistency--what I want is a hard pedal all the time, or at least a long pedal that stays in the same place. I do find the fluid is always discolored (just a little in each caliper) after a bleed at all 4 wheels. So some of this seems fluid related...bleeding did help a bit on my second event at Summit. (1 mentioned above I did bleeding and also just changed pads to a slightly better pad). Also I'm not putting old fluid or Dot3 in there...only Motul and only 4-6 days before the event from new unopened sealed containers(I don't do it weeks and weeks in advance...I don't want any moisture).

BTW--if the pad tapers even a little along the width--not along the length as you said--is this the sign that the calipers are spread and need to go go go?

Thanks

John Shiels

I think even a new caliper gets hot it will taper a pad in width.

Sidney004

Measure the parallelism of the brake caliper between the clamping points. If the inner dimension(which clamps the OD of the rotor) is smaller(.005-.010) than the outer dimension(which clamps the ID of the rotor) the calipers are toast or will be shortly.

sothpaw2

Not sure what you mean by inner/outer dimension. Do you mean to measure the parallelism of the caliper by measuring the distance (in the direction of the pistion bore; along the width of the car from pass. side to driver's side) of the parallel planes (the plane of the circular face of the rotor) that hold the pads?

I think the calipers might be done--do have some taper along the short dimension of one pad, not the length (length of pad= trailing/leading edge of rotor contact) in addition to the usual length taper Bill showed in the photos.

vms4evr

Unfortunately you're fighting a loosing battle. I was bleeding often, restacking pads daily, and it helps. But you're not going to solve this short of replacing the stock caliper. If you can run a less aggressive pad and keep the heat lower it might help. The SS pistons should help. I've gone through 2 sets of C5 front calipers and decided to switch.

I went to Wilwood SL6R fronts. 6 piston. Much more consistent braking. No need to pump the pedal before the braking zone. The brake feel is almost consistent all day long. I don't bleed the brakes daily anymore. My rotors also last longer. Now I'm also running a 2 piece rotor.

Which brings me to that part. You might consider a 2 piece rotor. The aluminum hat seems to be part of the solution. Better heat dissipation away from the rotor. At least that is what I noticed.

Ran the Wilwood H and A pads. The H pad is not bad at all for DE days and wears great. It is also much easier on the rotors. I ran Hawk DTC70s. As much as I like how intense they are, they eat rotors like candy. I think with the 6-piston they also make the front get unstable as they brake too hard! Even with 315 Hoosiers on the front. I lost some stopping power and distance but get much better wear and less overhead at the events. I'm not screwing around with my brakes all day and I'm not running down the road to cool the car after every session.

For racing or TT you may not want to give that little bit up in braking. For DE it isn't that big a deal.

Sidney004

yes

sothpaw2

Graham,

Nice to hear from you! Still remember your C4 exhaust thds form years back on the other forum.

Yeah the H pads rock. Absolutely no going back for me. Tried a few others, nothing compares. With this tapering going on, I need something wear resistant.

Do you think the Ti plates would help as much as the SS pistons--did you try either one? Seems not to many swear by either.

2 piece rotor a good idea--provide thermal path back to the hub. Are yours a bigger than stock size? Do you run 18" front wheels? Would want at least the option of keeping the 17" size. I want to say Wilwood makes one like that....but do they supply the brackets? I remember that being a hang up.

Thanks,

Andy

USA1C5

I put the Titanium spacers behind the pad but I can't say yea or nae on effect until after my next track day. This is on stock C6Z06 calipers. We will see March 14 at VIR with 10/10ths.

trackboss

FWIW, the titanium shields are the easiest and least expensive to install. I have them on my stoptechs. No hard data to prove anything, but keep in mind that the shields are a layer of protection between the pad and pistons and seals. With no shields the heat will be directly transmitted from the pad backing plate to the pistons. The seals will get both radiant heat from the pad backing plate as well as direct contact with the pistons. That all being said, the shields are very inexpensive so why not use them? Might even be a good idea to get two sets so as the pad wears double up on them to keep the pistons from extending too far out of the bores.

USA1C5

I got the 1mm titanium shields they also have the titanium shields in .5mm. They information I got was that the 1mm shields can only be put in after pads have worn down a little but the .5mm shields can go in with new pads.

0Todd TCE

Both the Ti plates and or the ss pistons seem a great idea for boiled fluid issues. But you never really referenced that as a problem. If you're not boiling it now then I'm not sure that adding one or the other is more than a band-aide solution to other problems as some have mentioned. The nice thing about the shims over the pistons is that they can also serve as wear spacers for piston to bore compliance. But...most Ti shims are quite thin so even that's a bit of a stretch.

sothpaw2

Well I do notice when I bleed the brakes after a full day that I get darker fluid out of each caliper--all 4 corners but ?? maybe I can say more up front. I do swap the pads to even the wear but maybe I was only doing that between events, not after the 1st day during an event.
I'm also probably not "double pumping" to help with knock back.

So I can do that & be sure to swap tapered pads after each & every track day. But just wondering if say the Ti shims are worth it...have they made a noticable difference as experienced (tested) by anyone??? Same w/ the SS pistons.

Thanks

Andy

John Shiels

SS pistons and shims work. Shims are like dressing in layers for the cold.

RDnomorecobra

where does one get these shims?