0Todd TCE

I'm really sorry guys...obviously I'm not trying to mislead you. Only using the tools at hand to show you the whys and hows. Having the wrong tool doesn't help.

I did post the info and image on the Wilwood facebook page tho in hopes of helping others.

After all that I sure hope someone doesn't come and show me the car is FS!

Kid Vette

PM sent. Ignatz and I aren't too far apart. Sure you don't want to make a trip to CA and swap some calipers? There's probably a few more in this area. It could be a "Caliper Swapping for Beer Tour" like the tours Lars used to do.

69427

Please feel free to check the accuracy of post#27.

0Todd TCE

Catching up here, what's the question of accuracy now?

waljr

here's a pick of the back of one of my D8-6 calipers. The arrow shows the correct rotation, ie big piston trailing.

Kid Vette

And what do your instructions say?

waljr

bugger all.
Same picture as post #22, absolutely no mention of piston orientation & a later picture (Figure 2.) looks like the caliper is offset slightly.

ignatz

Am reluctant to change back, at least for a while. What is the downside here?

- Uneven wear
- Reduction of grip at the track
- might be a little grabbier?

with regard to the last, I was a little surprised at locking up my fronts at an autoX. Could the larger piston at the leading edge be creating a self-energizing effect?

zwede

The fronts are supposed to lock up first. If the rears lock before the fronts you'll spin the car.

69427

You still seem unconvinced that C3s are rear steer.

ignatz

My conjecture is that the larger piston in the leading position pushes the front of the pad down harder leading to earlier binding. Just saying it seemed different when I switched to the illustration.

Solid LT1

Cliff the main reason for the different piston diameters is to prevent tapering of the friction material on the pads ( reasoning behind this, as friction material heats up it should have more grip until it reaches maximum temprature so the leading edge of the pad runs cooler than the trailing edge, by changing piston sizes, it reduces pressure on the hotter part of the pad.) You will see even more taper wear on your pads with the piston orientation reversed, there also might be a difference in the brake balance. Stock C2/3 Vettes tend to lock up their front brakes on extreme use, your front brake bias might actually be a little worse. In normal street driving, probably no difference, in panic stop situation....earlier front lock up giving loss of directional stability.

waljr

all the d8-6 caliper boxes are label left or right as well.

The supplied bolts were to long unless used with the supplied washer + a spring washer.
My front calipers were centered perfectly, the rears were slightly offset.

0Todd TCE

No sir. I did bring it to their attention and you may see the graphic change in time. 'Course with that stuff...could be quite a bit of time!

KJL

Finally started install yesterday. So far it has been a breeze. I initially bleed using a vacuum pump and mason jar, then I do a final bleed by pressurizing the master cylinder. The pads are not exactly centered in the rear caliper, about 0.03" off. The part I am a little concerned about are the bleed instructions that say for some installations (not mine I hope), the caliper needs to be rotated to the vertical position to remove all the air. I saw this after I installed the caliper. The line length and design will not allow for rotation. The caliper would need to be completely removed and wood blocks inserted between the pads for that to work.

I think what I will do on the other side is loosely mount the caliper, bleed then remove and bleed with it in the vertical and see if any additional air comes out. If it does, I will remove the other side and re-bleed. Pedal feels good however.

0Todd TCE

Only the rear calipers, if top mounted, will need to be removed. Or at least in some sort of vertical manner placing the bleeder nipple at the highest point.

Kid Vette

That's really handy when you also have to shim the calipers. I superglued the shims to the calipers. Truly an engineering marvel. And not in a good way.

KJL

Would this be considered top mounted? I also included a pic of the rig I use to pressurized the master. So simple it is stupid.

ignatz

There is potentially a little air in the piston under the 'd' in Wilwood. The lower the trailing arm and the higher the front of the car helps I suppose. And rotating the caliper some. I didn't bother, my brakes are close to excellent pedal but possibly this is where the last bit of air resides.

___________
compliments on your pressurization rig. Think I will adopt it. How much pressure are you applying?

KJL

I will pull it and check, I will also add some washers to center it better. I will let you know. Between5 and 10 psi. I slowly increase pressure via a regulator until the brakes start to clamp down. You may have to stroke the pedal to pressurize the lines. Works like a dream. Just need to keep an eye on level. Vacuum works fine for getting bulk of fluid through system. I put a couple of small holes in small bottle of dot4 and turn it upside down in reservoir while I do that part. The only reason why I finish using pressure is the vacuum method pulls air in from around bleed screw so it is impossible to know when all the air is out. I think they sell a special bleed screw for that bit never had much luck with them.