Azrael91966669

since im tired of my stock wheels not being aligned properly the c4 rotor dosnt let the wheel sit on the hub ie causeing a need for hub centric rings that nobody makes wheel cant sit on the lifted part of the hub

i was wondering if there was a way to just install a 1le rotor

im currently already useing 1le rotors turned to hubs on my c4 12inch setup
i also noticed the caliper has room to fit a larger rotor i just wondered if the spaceing would be correct

novaderrik

the 1LE package was just a Caprice HD rotor with the smaller wheel bolt pattern and wheel centering hub with C4 Corvette calipers on a modified spindle..

regarding your current problem: your lug nuts should center the wheel without any problems, unless you are running some old unilug Cragars or something..

Azrael91966669

no the factory wheels are hubcentric not lug centric trust me ive figured this out the hardway you can even see the differance just spinning the wheel with the rotor on and the rotor off with it off the wheel spins true with it on you see a noticible hop

i know its a corvette caliper and i know the adaptor "bracket to spindle" is the same im just not sure if i can use the 12 inch caliper since the 1les use the 13 hd caliper
but the 1le rotor isnt as thick as the 13hd rotor im also not sure if the caliper bracket can be used

Base91

iTrader: (1)

Take a look at Lukeskaff.com there is a list of all the parts that work together and which don't.

Azrael91966669

thank you very much for the link it answered my questions

novaderrik

the stock lug nuts will hold the wheel centered unless there is something wrong with the seats machined in the wheels. i didn't have any problems with the GTA wheels i was running with C4 brakes on my 71 Nova with the rotors completely covered the centering part of the hub. i put i don't know how many thousands of hard miles on that car like that..

Azrael91966669

example is rotor has good runout ie none wheel and tire are with in spec

ive been dealing with this problem for years now we only solved the problem when i worked at a dealer that had an on-car balancer older vws can have this issue
when you remove the rotor and set the wheel on it balances perfect
install rotor and wheel its out of round
is it possible the wheels are damaged around the lugs i suppose they are orginal
but ive done with it front and rear wheels and out of 3 sets of wheels everyone of them have this issue i cant find hubcentric spacers to fit the small gap i mean honestly there is bearly a gap maybe a mm but enough to throw off the installed wheel and tires runout

Twin_Turbo

iTrader: (25)

You can use 1LE rotors with the C4 HD calipers, called J55. Came as option, std on ZR1 and Grand Sport. Same as the baer track calipers (they are just modified grand sport castings with their name on them) the problem is, you still have to use th 1LE abutments to clear the disc hub, the C4 ones wuill only clear if you convert the 1LE rotors to hubs (cut off rotors) and slip on some J55 C4 rotors (13 x 1) then it's a bolt on deal with the same bracket as for the JL9 std 12"x .9 rotor C4 setup. The JL9 calipers will not fit the wider rotors.

Azrael91966669

im wondering how hard it would be find 1le brackets lol

JamesC

iTrader: (5)

http://www.spohn.net/shop/1982-1992-...es-Components/

JamesC

Azrael91966669

so another 300 just so i can get rid of a vibration maybe i just need to find a set of stock rotors with a longer hub ring then cut them down into hubs

87350IROC

iTrader: (2)

Or you could just get custom hub rings made. Should be no more than $100 and many places offer this service.

Azrael91966669

i some how have to get rings made from for about a mm of play its sad that thats all it needs yet causes a horried vibration above 55mph it honeslty feels like the tires where never balanced above 65 it bounces the dash up and down
below 50 you would never know it had any problem at all
if i would have known that this could have been an issue i more then likely would have just gone with a differant setup i just wonder why so few people have this issue when they do the brake upgrade

87350IROC

iTrader: (2)

The 12" C4 must have some really thick hat (doubt it). Here is my old setup with C4 HD rotors. Plenty of meat on the hub centric portion.

Azrael91966669

my lip is not even close if i had that much lip this would not be an issue as all the rotor takes up all of the lip
these are the pics from when i installed the setup

i wonder if its because the hd setup uses 1le rotors cut into hubs
im useing the stock rotors cut into hubs

novaderrik

some wheels have a pretty big chamfer on the center bore for some reason- probably to allow them to slide on easily.. the C4 rotor might just cover up enough of the centering part to not make contact.. but like i said before, i didn't have any problem on my Nova that didn't have any of the machined part of the hub sticking out- the lug nuts centered it.

Azrael91966669

ive personaly tried 4 sets of wheels all suffer the same fate but they are all third gen wheels that are hubcentric 2 differant sets of rs wheels ive tried both front and rear
1 set of iroc wheels also tried both front and rear
1 set of 15 rs wheels
i have no lug centric wheels to try and put on

DrNBody

So....do 1LE rotors work with C4 HD calipers? Your post contradicts and is very unclear.

Twin_Turbo

iTrader: (25)

no, the 1le abutments are curved for rotor hat clearance, C4 J55 caliper abutments are not, and they have the holes drilled lower to only work with 13" rotors. The only way to make it work is use the C4 J55 caliper with 1LE abutments. Better to just get some C4 J55 rotors anbd have 13" (ish) brakes

DrNBody

Ah, ok, understood, thanks.

I am trying to figure out what I can use with 1LE rotors.

92RS_Ttop

iTrader: (3)

You currently have the C4 "standard", ie non-HD setup, correct? That's the way it sounds from reading your posts. If that's the case, are you using C4 front or rear rotors? From what I've read on this swap(read a lot as I will be doing this swap myself once I get the hubs), you need to use the rear C4 rotors, not the fronts. Also, have you tried a different set of C4 rotors? Maybe the ones you have are just a bit off. I saw where you checked the runout on them, but that is usually only checked on the pad surface. If the hub surface is not flat(meaning a variation in thickness from outside against the wheel to inside against the hub)it could be preventing your wheels from mounting flush and true, causing your problem. From your pics, the rotors you have flare out from the hub surface to the pad surface. I remember reading somewhere, I think on lukeskaff.com, that a shoulder had to be cut in the outer edge of the turned-down hub to accommodate that flare in order to get the rotor to sit correctly on the hub with that style rotor.

cosmick

When you're trying to figure out a mix-n-match brake system, the easiest way to make progress is check the specs for rotor thickness of whatever you want calipers from. You can even do this on RockAuto, but NapaOnline tends to have more help. If the calipers are for 0.81"-thick rotors, you'll never get them to work with 1"-thick rotors. The fudge factor is the new rotors can be between 1 mm too thick, to 3 mm too thin. Beyond that, forget it, find different rotors or different calipers

DrNBody

I have the '86 J65 setup as of now...so 1 piston 10.5" fronts. I am trying to figure out what caliper I can use behind my 16" IROC wheels, using stock 1LE rotors, with which brackets.

DrNBody

Yes, I am aware of using rockauto as reference. been using them for that for years!

cosmick

All through the '70s, Gm offered 12" discs inside 15" wheels, both steel wheels and aluminum wheels on the 'vette, and 15" steel on the big wagons and police cruisers.
So with some calipers, it should be possible to get 13" rotors inside some 16" wheels, no idea which calipers for which wheels.
The real issue is rotors with the correct hat height, then calipers that aren't too thick on the wheel side. '98-up 2WD S-Blazers had 2-piston aluminum calipers, they might work with 1LE rotors if you do custom mounting for the calipers. But you may as well just go 1LE.
Stock third-gen wheels were never intended to clear 4-piston calipers.

92RS_Ttop

iTrader: (3)

Sorry, I was actually replying to the OP. I didn't realize this thread was started in 2012. 1le rotors were tried with the C4 calipers, and it was found that the rotor thickness was too much for the calipers, or the mounting bracket would be too thin to be safe. I can't remember which off the top of my head. This was from a long thread in this forum from a while back:

https://www.thirdgen.org/forums/brak...-may-just.html

Azrael91966669

odd that im not getting updates on this thread via email sorry here are my specs and a few updates
I am running C4 12 inch rear rotors and non HD calipers also I incorrectly stated that my hubs are made from l1e rotors there made from stock rotors the 1le's do have a longer centering hat but apparently wont work with the 12 inch setup as then the rotor would stick out much to far .
im still dealing with the vibration issue ive tried a few different c4 rear rotors all have the same issue the hubs do allow the rotors to lay flat the rotor run out is perfect on both sides . the problem was found when I used on car wheel balancer it also can chec the runout of the rotors on car aswell . if I took the rotor off and just popped the wheel and tire on the hub perfect run out if put rotor on out of spec remove wheel and just bolt down rotor perfect run out we noticed everytime the runout was different then noticed realized that gm wheels are hubcentric and the rotor takes up to much of centering hat on the hub they cant make a hubcentric ring that small apparently it would break to thin ive called around

also the aluminum wheels and tires will roadforce balance perfectly off the car they have so little side to side that is completely in spec so there not bent

it all seems to be the centering hat issue the rotors perfectly flat against the hub it was machined correctly

I looked into doing the l1e stuff it would cost more then what I already have and the caliper bracket is n/a the spindle mount bracket is
I also looked into just going to the j55 parts but then I need the 1le rotors made into hubs then I need a new spindle mount bracket and need the caliper bracket no one sells them outside of getting a complete kit and id need the rotors and calipers basicly only thing I have that is correct is the spindle is already modded lol
I had chatted with ed miller from flynbye he understood the problem and he was going to look into it and at some put bring out custom hubs but he never responded if the ones that he added to his site had a longer centering hat "he was super helpful otherwise as this wasn't a kit I got from him"

I guess the next option I have is to mill down the face of the hub so that It exposes more centering hat but Im worried that it may weaken the hub at that point

Azrael91966669

apparently the c4 HD uses the 1le rotor milled to a hub and those rotors have a much longer centering hat area almost double the width of the stock 3rdgen rotor once turned into a hub

I suppose I could just buy 2 1le rotors have them milled into a hub and then use C4 12 inch front rotors as it will have the correct offset but Im not sure if that will work

added attacments to show difference 1st pic is 1le 2nd stock rotor you can see the difference in thickness of the centering area