first I think the inspection place had a point, something I missed

They claim my brake pads stick way too far ABOVE the rotor and the brake area is reduced too much (well not compared to stock, lol), looking at it now they have a valid point but I can't figure out what's wrong

I just put the brakes together, I have maybe 50 miles on it all and it works great.

- rotors seem to be the 12.8" kind, almost 13" (I am 99% sure it's not the 12" rotor). I believe this makes them the C5 rotor.
- brake pads I got with the calipers & carriers, so I assumed those were stock as it all came assembled and dirty/stock looking.
- calipers were ebay purchase , LS1 kind
- bracket I purchased years ago from nethirdgen.org contact, I forget who, but it's the C5 kind (the nice round edge one).
- spindles I drilled per instructions, using those dust shield holes IIRC
- everything assembled fine

it's almost as if I need a 13.8" rotor but I'm not sure it would fit into the caliper

this is the bracket I have (borrowed from luke's page), now I Didn't measure mine, but the shape and location of holes is identical, I'm 99.9% sure that's what I'm using.




here are the pics, notice how far the pads stick up over the rotor in one of the pics, that's the issue, also it seems too far OUT from center of rotor right?

 

I must have done something stupid, it's not like the bracket bolts in upside down or the caliper carrier , WTF Is left I bet I'm missing something obvious

 

you have the ls1 caliper for a firebird? the corvette abutement bracket lowers the mounting point half an inch. your in my boat. i had to " revise my bracket" seriously

any further questions on this i may be of help to you. lol been dealing with it for months

 

found an old pic when I had it on the bench, I think this is how it's assembled, you can see the bracket I have , only thing missing is a hub which shouldn't have anything to do with this.

 

I have no clue what caliper I have to be honest as I bought it used so I can't trust any of it, I Think I bought LS1 and I thought LS1=C5 caliper except the cooling ribs or something were different or of better material.

so you think I have LS1 abutment/caliper carrier? which is different from Corvette? So the fix is a new corvette abutment bracket?

 

http://lukeskaff.com/?page_id=333

- according to that the calipers are identical size-wise between f-body and corvette
- rotors differ, f-body is 12" , corvette is 12.8" , I believe I have the corvette ones
- abutment brackets may be different, fml lol , I'll go hunt down some part numbers I guess

 

gonna pm u.

 

so it seems the fix is to order CORVETTE abutment bracket, not the LS1s I seem to have + new pads , the part number seems to be 12455799 and they are about $40/ea

 

False. What you have there is a Vette bracket. Since the abutment successfully bolted to the bracket, then you have a Vette abutment. The real questions are:

What calipers do you have?
What pads do you have? The C5/C6 and LS1 pads are not the same but will slide into both calipers.

Please measure the diameter of your rotor.

I don't understand how you could not have seen this when you put the brakes together.

John

 

Are the rotors the same thickness? If they are and this assembly clears your wheels they just order the 12.8" rotors instead of the 12" that you seem to have, if not, then get some LS1 f-body brackets to move the calipers in... maybe i'm oversimplifying this... why make a bigger deal of it if the calipers are the same?

 

I did measure the diameter as I said above, it's definitely 12.8"

I also said I have no clue what pads I have, bought it all used and while I was testing the brakes I just used the pads that came with calipers, I would replace them before I do any autox but for now wanted to wait

I believe I have LS1 calipers, at least that's what the ebay listing claimed them to be which would then go against your bracket suggestion as I got the calipers+abutment+pads all together in 1 auction from a junkyard type of place, they wouldn't piece together 3 sets of dirty parts from 2 cars.

 

I don't mean to be ungrateful, but is there really still no clear consensus on this stuff all these years later? I Literaly started the C5 brake build when it was cutting edge stuff, probably 8 years ago? lol , I just never got around to finishing it all until now and I'm still finding many people who don't know what's what, including myself (sadly).

I have 12.8" rotor, IDK what abutment bracket I have, I am 90% sure I have LS1 caliper though. Well I ordered the corvette abutment ones already anyway so whatever, guess I'll find out, but would anyone have a pic of the LS1 vs vette brake pads?

I'm so

 

it was pointed out to me last month why u need the c5 abutement brackets. they have the same bolt spacing. either one will bolt on but its mounting height that is affected to accommodate the bigger rotor. ill try to link stuff but have not yet mastered that function.

ur picture in post #4 shows the mounting hieght, if you compare the c5 bracket youll notice that the mounting points are the same height as the front support of the bracket.

 

corvette caliper. not the best pic but its autozones image. notice the height of the mounting bracket

 

compare the height with the one you have in post #4

ebay image, better pic

 

yeah I'm trying to find a pic to calm my fears down (of ordering wrong stuff again ) but it sure sounds you're correct, even on luke's page the two different bracket designs (not abutment, but the adapter) seem to have hole spacing at about 5" apart so the abutments seem interchangeable as far as bolting them on goes, but alignment is out of whack

 

yeah makes more and more sense, thanks fireburd

Once my parts arrive I promise to actually have a nice comparison photo of the two brackets for any other schmucks down the line that buy the wrong stuff like I did.

 

just be nice to see them side by side. im sure a member on here has the 2 kicking around? peruse the brake section and youll get some good hits. i posted recently about the same subject.

 

another decent photo for the temp archives, everyone can notice the front curvy "support" of the abutment bracket , notice that it's pretty much OVER the mounting bolt holes

then scroll up as fireburd said to my post #4 and see where my curved front part of the abutment is, it's good 1/2" above the mounting holes.

clearly they differ in that aspect

 

I definitely searched my *** off, but I'm not the biggest fan of TGO search engine

nbd, I ordered the C5 ones already as we talked about so either way there will be a pic soon, I'll send it to luke since his page seems to have really good info

http://lukeskaff.com/?page_id=355

 

Boy this is a mess.

I looked at the parts I have here.

It looks like what you have is LS1 abutments, LS1 calipers on a C5 bracket and C5 rotor.

It makes complete sense that this does not work. The LS1 abutments are too offset for that combination. The Vette abutments hold the caliper closer to the center of the hub. Vette abutments should solve your issue. Depends which pads you have. They are a very similar shape.

But you will likely need new pads anyway since your likely have a nice step on them now. Make sure to get Vette pads.

Finally,

The cooling vanes in the rotor pictured are pointing the wrong way. You have a right rotor on the left side. You are also missing an anti rattle clip that goes in the pad inspection hole of the caliper.

John

 

There is very clear consensus. Your issue is you used LS1 caliper and abutments with a C5 conversion bracket and C5 rotor. I have never seen anyone claim this would work, because it doesn't. You have proven that. It is not surprising, the dimensions are different.

 

nowhere did I claim this should work, I was unaware of the difference in abutments but there is still much disinformation which you yourself help spread

just look at your first comment claiming that I must have vette abutment since it bolts to a vette bracket, that is simply incorrect and yet you were sure of it, then you switch sides and tell me I have an LS1 caliper with LS1 abutment, so which is it? I'm not trying to be a dick, but we all jump to conclusions at times, mine was that the abutments are identical.

Even the best websites I could google did not mention there's an actual difference in abutments or more specifically WHAT the difference is. The only thing they get into is that calipers are interchangeable. Trouble with forums is that people (at least I do) link to pics off image hosts that eventually purge their database and pics end up broken so few promising threads with pics that I stumbled on had nothing that could help me oh well.

I am sure it has been covered million times in many years, but I'm hoping this thread helps someone else, it's not a big deal and easy fix I hope when parts arrive.

 

That is correct, I was wrong, then corrected myself. I was confused due to the strange collection of parts. I apologize and will refrain from helping you in the future to make sure it doesn't happen again. My help is worth what you paid for it.

To answer your questions. I looked at both parts SITTING ON MY DESK, not on internet photos. What you have is the LS abutment and LS calipers. The reason your combination does not work is because the LS abutments hold the caliper further away from the center of the hub and the Vette abutments. The LS abutment to spindle mounting bolts sit roughly 1" closer to the center of the hub than the Vette. The difference in rotor radius on only ~0.4. That is why your pads are overhanging by roughly 1/2".

When you install your Vette abutments, make sure to use Vette pads or you are going to have problems again. Please also make sure you get the rotors on the correct side.

John

 

thanks

 

Thats a keen observation, I didn't even notice it and had to go back and look. He knows his brakes.