Has anybody else had the problem with the concentric rings being too thin to center the 12 inch rotor properly? The backside of my 12 inch Corvette rotor hat has a bevel to it which is deeper than just one concentric ring is thick so, I end up having to use 2 per rotor in order to bring the ring flush with the hat face. With one it doesn't reach the end of the inside bevel on the inner side of the hat hub center which means I am 4 short in order to do the back brakes

I noticed that when looking at JohnF's rotor and rings at the last NTFC meeting. Without looking at a hub to see how tall the machined surface that the ring seats against is I couldn't tell if leaving the ring seated in the rotor would reach the hub.

James

I suppose I could just use 2 per side> I wonder if anybody has 12 inch rotors that don't have the bevel on the backside.

Im sorry these are diving you problems Erik! Would it be possible to find, say some exhaust pipe, that will fit snugly around the hub? If you can find the correct size, you can then cut "spacers" out of the pipe to bring the centering rings out far enough.

quote Originally posted by AutoTech: Im sorry these are diving you problems Erik! Would it be possible to find, say some exhaust pipe, that will fit snugly around the hub? If you can find the correct size, you can then cut "spacers" out of the pipe to bring the centering rings out far enough.

Its just a minor problem ..with 2 sandwiched it works ..I thought about putting some sort of spacer like what you suggest but I am wondering if the rotor itself is the problem. What i would like to know is, are all 12 inch Corvette rotors beveled like that on the backside

I've read that some people were having this problem. I think different rotors don't have that bevel, or maybe not as much. I'll bet someone will reply soon that has experienced this.

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Adam is correct. Some rotors are square cut, some are thinner. Sluppy makes his exactly to the specs as posted on Bubbajoe's site and in his thread and I ran into that as well. I made a new pair, same OD/ID but thicker. I measured my rotors and made them .010 thinner. Any competent machine shop should be able to make a pair for you for very little money.

This isn't a mistake on Sluppy's part, it's a normal production variation of the Vette rotors.

John Stricker

I will try to help... This is for an 88 Fiero only

First get 88-94 front rotors. You will need 4. NOT the HD ones. I got mine zinc plated from ebay.


This shows the placement of the bracket to the front hub.

Rear

Notice how it "sticks up higher than the stock placement.( sorry, I just like this shot)


Finished job.

[This message has been edited by revin (edited 02-07-2007).]

quote Originally posted by revin: The only problems I have had was, It seemed real close at the top of the rotor and the caliper. I filed it down a little bit with a file. and got a better looking gap.

I seen that myself when I initailly fitted the brackets and calipers


as far as LCA hitting on the rotor it looks to have enough clearance on the drivers side ..one thing I did not realize I would have to do before doing this upgrade was the dust shield would have to be removed

I am wondering if anybody has just done the fronts and if they have any info on how it performs afterwards. I plan on posting a thread on the before and after the upgrade

I posted this info in the 12" brake thread. Found here in 2nd post:
https://www.fiero.nl/forum/Forum2/HTML/063914.html

quote "Place the ring created from Bubba's drawings onto the hub and install the rotor. Using two or so lug nuts, tighten the rotor against the hub. We found that with the larger taper inside our rotors, the supplied drawing ring didn't work. While the ID and OD were perfect, it was too thin to be usable. We had to make a trip back to our machine shop and have him make us new rings that were twice as thick."

Just the front would be scary I would assume, they would probably lock up way to easily.

quote Originally posted by Jncomutt: Just the front would be scary I would assume, they would probably lock up way to easily.

Well, I am about to find out. West Coast Fiero recommends disabling the rear proportioning when just doing just the front to "compliment " the fronts stopping power. Don't worry, I doubt if I am going to mess with that though and will rather put the rear kit on if I feel it needs it.

That is why you should get zinc plateing
No rust on mine.

It would be much appreciated if someone could take a picture of where to grind as my suspension is apart to go off to get powder coated. I bought sluppy's kit last month and would rather grind now rather than have to destroy my pretty powder coated finish. Thanks!

It is the "lip" part of it. The very edge looks like "extra" metal pounded flat.
you just grind off a little bit. don't go too nuts or you will screw up the arm itself.

I will look for a pic...

quote Originally posted by Erik: one thing that concerns me as well is the unused area on the inner face of the rotor. It looks like it will just rust since it wont be used so, for cosmetic reasons I figured I probably should paint it with some cermanic caliper paint

If your rotors are not plated that area will rust and it will not look pretty. I suggest you do paint it.

quote Originally posted by jscott1: If your rotors are not plated that area will rust and it will not look pretty. I suggest you do paint it.

Yeah this is after a drive ..it looks like I'm going to have to paint out a little more from the hat


Of course my car is a bit dirty from driving in this winter weather although I never drive it when its sloppy wet

[This message has been edited by Erik (edited 02-09-2007).]

quote Originally posted by Erik: I am wondering if anybody has just done the fronts and if they have any info on how it performs afterwards. I plan on posting a thread on the before and after the upgrade

We'll see really quick. I am in the process of doing "just the fronts" now. I should have things going again and be able to report on them in a couple of days.

I really hope things aren't "scary" and the fronts lock up. We'll see, I guess.

quote Originally posted by JohnF: We'll see really quick. I am in the process of doing "just the fronts" now. I should have things going again and be able to report on them in a couple of days. I really hope things aren't "scary" and the fronts lock up. We'll see, I guess.

The fronts will lock up if you are not expericenced or used to them as it were but once you get comfortable with them you can stop real quick , much quicker than stock without locking them up and even if you do all you have to do is back off a little and they will unlock. I am really begining to like them as is and probably will just leave the backs stock

[This message has been edited by Erik (edited 02-10-2007).]

That's odd.. I have 12" Corvette rotors with the West Coast Fiero adapters on my 88 with the 88 calipers and the pad sweeps the whole rotor surface area up to where it is stepped down in the transition to the hat. There is no area left clear that was swept on the 'vette.
Freshly plated rotor:

After being driven:

You can see the pad sweeps the entire engineered swept surface on the rotor from very close to the outer edge all the way to the groove that transitions into the hat.
Does the outer edge of the pad overhang the rotor? Perhaps the calipers are spaced too far out with these other brackets..

quote Originally posted by Steven Snyder: Ahh I see, Erik.. yours did not have the groove machined into them where the swept area stops. Yours were probably import rotors?

Import rotors would also explain the production tolerances.

quote Originally posted by Steven Snyder: You can see the pad sweeps the entire engineered swept surface on the rotor from very close to the outer edge all the way to the groove that transitions into the hat. Does the outer edge of the pad overhang the rotor? Perhaps the calipers are spaced too far out with these other brackets..

No the pad is positioned just shy of the outer edge


It looks like from your photo that you still have an area on the inner part of the disc that is not hit by pad, just like mine. I do have agroove where the swapt area transitions to the hat but its not wide as yours and yes they are import rotors

quote Originally posted by Erik: Steve can I see a picture of your West Coast brackets with the calipers mounted to them.?

I don't have any pics with the rotors off so you can see the brackets.. When I take the rear apart again to replace a bearing I'll try to remember to take some pics.

So three of my concentric rings look like the one on the left, yet one of the looks like the one on the right. The taper starts a lot closer to the outside edge and give the inside surface a lot less area. Visually its hard to tell if it caused the inside diameter to be smaller, so gotta grab my measuring calipers and check. Is this normal?

Bump - anyone?

quote Originally posted by Erik: It looks like from your photo that you still have an area on the inner part of the disc that is not hit by pad, just like mine. I do have agroove where the swapt area transitions to the hat but its not wide as yours and yes they are import rotors

The entire flat surface of the rotor is swept by the pad. If you look at the brake pad in the pic you can see it goes all the way up to the groove.
The lines you see are because the doofus who slotted my rotors didn't run the slots all the way across the swept area, so the end of the pad past the groove wears differently and unevenly.

Anyone have an answer?

quote Originally posted by RandomTask: So three of my concentric rings look like the one on the left, yet one of the looks like the one on the right. The taper starts a lot closer to the outside edge and give the inside surface a lot less area. Visually its hard to tell if it caused the inside diameter to be smaller, so gotta grab my measuring calipers and check. Is this normal?

I would say that it is not normal ..mine are all like the left one

quote Originally posted by RandomTask: So three of my concentric rings look like the one on the left, yet one of the looks like the one on the right. The taper starts a lot closer to the outside edge and give the inside surface a lot less area. Visually its hard to tell if it caused the inside diameter to be smaller, so gotta grab my measuring calipers and check. Is this normal?

The left one are the right ones.
The one on the right looks funny. I would not use it.
Get another one like the other three.