69 Camaro at Best of Show

[Cris@JCG]

I will keep you in mind when working on a floater.. whose parking brake do you have now??

Originally Posted by Payton King

about building me a floater as well. I am going to for go the parking brake as mine does not work worth a crap now.

As long it is a floating caliper.. In the long run it will be be the cheapest solution..

Originally Posted by 69MSA

Cris, would a single piston parking brake from Brembo help simplify the issue of putting one on a full floater?

Matt

[Payton King]

Not their fault as it is a good design. Using Lokar hand e brake. Not enough throw or leverage.

[GregWeld]

I discovered a miracle fix for all these axle leaking brake knockback issues!!!!


A set of 6.70 X 15 - 2 ply nylon tires like we used to run on the mid year Corvettes....

Never experienced any issues back in the day!


EEEEEEEEEHHHHHHHHHAAAAAAAAAAAAAAA

[makindue84]

GregWeld. I think that a set of 6.70 X 15 - 2 ply nylon tires will be effective in our car. I hope there will be no issues back then.

[Matt@BOS]

Well, I took the car out to the track last week with the group that went out to Adam's Motorsports park in Riverside. The track is pretty much just a big kart track, which isn't such a bad thing as it's quite technical and has got a good mix of turns. All of the changes we made to the car made a huge difference - I mean a night and day difference. The car might understeer a little turning in now, but it's not bad at all. Exiting corners is insanely easy the way it is set up too. I can almost plant the gas and take off, when it's almost straight I can let it go wide open, and the car will step out just enough to straighten out. Then it just goes. The only issue I had was bad pad knockback issues. I had to tap the brakes once to get reasonable feel back, and twice to get the pedal all the way back to the top. On my last lap I forgot to tap the brakes up after a long straight and the pedal fell almost to the floor, needless to say, I put the front two wheels off track.

So, I've been talking to Cris G and his Wilwood friends, as well as Tobin at Kore 3 and have decided to try a somewhat affordable solution to lessen the apparent knockback. For now, I'm just going to go with a C6 Z51 rear brake setup and see how it works. It's a floating rear caliper, and I don't think I need the huge 4 piston setup on there now. It's not like I'm doing any serious, sustained roadracing, and even then I ran a Z51 'Vette at Bondurant, and never really noticed the brakes fading badly. If I'm not happy with that I'll swap to a 1" bore master and if the problem still persists I'll try the SET20 bearings that are shipping on Moser's axles now. I also decided to swap pads to the Hawk HP+ instead of the ceramics because the ceramics don't have much of an initial bite to them, especially when using manual brakes.

If none of this works, I think I'll be going Greg's route and getting a pair of 6.70 x 15s or maybe I can trade Doug for his rear drum brakes.

Matt

[DFRESH]

Hey, those are "Bear" one-off self energizing rear drum brakes on my car. Just need to paint those drums red. That's the one and only problem I don't have on the car, pad knock back.

You sure looked good out at Adams track---car sounded great also---

Doug

[The WidowMaker]

which ceramic pads were you running? did you ever run the stock padlets? what size master are you running on the rear now. i set mine up with 1" front and 7/8" rear for my manual c6z brakes. i hope i dont need another 1".

[Matt@BOS]

Originally Posted by The WidowMaker

which ceramic pads were you running? did you ever run the stock padlets? what size master are you running on the rear now. i set mine up with 1" front and 7/8" rear for my manual c6z brakes. i hope i dont need another 1".

Right now I've got the Hawk Ceramics on the car, which I ordered along with my brakes two years ago, way before I picked out a master cylinder, so I never ran the stock padlets.. When it came time to get a master cylinder Dick at Best of Show recommended the Wilwood 7/8" tandem piece, after all, it worked great for Steve on Bad Penny.

I really don't know enough about brakes to tell how your setup will work. I also don't know what you intend to do with the car, what other components you have, or how you like the car to feel under braking. For me, at least on a track, I like to have firm pedal feel with a bit of initial bite, which I think acts as feedback to help tell me how much I can modulate the brakes. Currently my combo gives me a little bit of squish in the brakes, even after a tap, then as I hit the brakes hard the car does decelerate well, but does so in a real smooth manner, especially with the DSE sub which doesn't allow for much front end dive at all. The feel of stopping in my Camaro is different than any other car I've driven, because despite the fact that the brakes really grab, you're never really able easily feel how much pedal travel you have until you lock the fronts up, and you can't judge how hard you're braking by weight transfer because the car doesn't dip down or lift up noticeably. Long story short, I'd give Tobin a call. If you tell him what you're after, he will be able to name all of the components you might need to set up the system exactly the way you want it to feel.

Matt

Oh, and before I forget... Doug how is your car doing? have you had time to fix the rear coilovers? I'm pretty set on heading back up to Adam's Motorsports Park Tues. Aug 10th and was wondering if you would be up for another track outing. If you're not ready but want to go you're welcome to ride shotgun.

[The WidowMaker]

thanks for the info matt. i looked back through the thread for the answers, but as you know its pretty long. tobin set me up with the brakes and he recommended the 1" front and 7/8" rear for my triple master setup. i am running the tapered bearing, so i hope i wont have any issues. oh, and my intentions are to run with you local guys when this damn thing is done......

have you thought about the carbotech pads? expensive, but the z guys seem to love them.

Tim

[Steve1968LS2]

Originally Posted by GregWeld

I still wonder if these valves wouldn't "help" (not cure) the KB issues on the discs you guys are using.

RP valves won't help knock back at all.. Think about how little two pounds (or even 10 lbs) of force is.. almost nothing.

Sure, they will stop fluid from gravity flowing backwards but they arn't going to stop piston knockback at all.

And you're right, you can't stop knockback with a MC.

Knockback is a mechanical issue, not a hyd/fluid one. Physical forces are acting on the caliper and pushing the pistons (by way of the pads) back into the calipers. The first pump of your brake pedal resetst the pad to the rotor and the next "pump" works the brakes.

The basic truth is that our axle ends aren't designed to handle high side loading like we get in autocross or road racing. If your axle tube is off center or warped then the problem is compounded.

A floating rear caliper will help mask the problem of the bearing/axle tube. If you want a rear fixed caliper then you need to

1) make sure your rear housing is as straight as possible to take pressure off the bearing
2) service your bearing on a regular basis (when it gets play in it)
3) Move to a stronger system like a floater or such
4) Move to a stronger bearing than can handle the forces involved better

Once I had my rear housing done by Currie my KB issue was nearly solved. But I'm sure it will creep back with more laps and require a bearing service.