I'm looking to upgrade to bigger brakes up front. I will be using 16" GTA rims with the brake upgrade. I have read that the LS1 brakes wont work without a spacer and longer studs if used with GTA rims?? That being said I am thinking of instead going with C4 12" or 1LE 12" rotor kits. Anyone using big brakes and 16" GTA rims? If so how has it worked out and what setup did you go with, who did you buy from??
I hear flynbye has a never ending wait and poor customer service. I also hear he is a good guy but that isn't a big plus if my parts don't show.
I have also been hearing the Bigbrakeupgrade.com is helpful and has good customer service. Anyone have a contact number for them???
I don't want to switch the front and rear rims and don't want the offset changed if possible. Thanks for any info.

 

I have a set of GTA wheels and they won't fit over the Baer 13" 2 piston track system I have on my car - actually the only wheels that clear them are the 91-92 Z28/RS 16" wheels. 1LE brakes do clear though...

 

The issue I'm hearing about is the caliper rubbing on the rim. Its not an issue with the 12" rotor just caliper rim contact...Anyone see this with GTAs and LS1s?
Also hearing C4 work without issues?

 

You pretty much have all the answers already.

1LE fits.
C4 12" fits fine.
C4 HD 13" do not.
LS1 fits with spacers.

Flynbye does make a "GTA Wilwood" setup that is 12.2 x 1.25 that does fit without spacers. But man is it pricey. Comparison to C4 are in the link below (post #21)

https://www.thirdgen.org/forums/brak...heels-get.html

I'm on stock brakes myself. So I can't comment on customer service for Flynbye or BigBrakeUpgrades.

 

Any of the kits will change the offset. The aftermarket kits will add the thickness of the rotor hat to the front track, which is around 0.3". The 1LE also increases the track about 0.3".

The 12" C4 kit is hardly an upgrade, not recommended at all. It uses a tiny 0.81" thick rotor. I would say the 1LE kit is your best bet for the money. I have been meaning to play around with a GTA wheel for fitment, but haven't gotten around to it yet.

 

Do these brake kits require longer studs for the wheel lugs? I've read the ls1 kits need longer studs which make sense being a spacer is required, what about the 1le setup? Does the 1le brake up grade need longer lug studs?

 

The stock replacement rotor I have here has 1.5" studs. In my opinion that is a bit short even for the stock setup. I recommend 2 1/8" - 2 1/4" for aftermarket brake setups in the iron hubs, or if you are using aluminum hubs, add the difference in hub thickness to the stud length. I use 2 3/4" studs in on my personal car with aluminum hubs. Remember all the aftermarket brake kits that use a slip on rotor effectively shorten the stud length by the thickness of the rotor hat. The rotor hats are typically about 0.3" thick.

The 1LE brake upgrade uses an integral hub/rotor just like stock and will therefore have the studs as part of the rotor, no change necessary. I don't believe a spacer is required for the GTA wheels.

If you add a spacer, they off course you need to add the spacer thickness to the stud length.

 

I have a lead on a LS1 brake setup for a good price local. As stated above I know about the clearance issues with the LS1 caliper and the GTA rim. I originally didnt want to do this but I think i'm now open to switching the front rims to the rear and vise versa, from what I have read this eliminates the need for a spacers. Also putting the rears on the front will eliminate the added offset .3" from the brake kit.

https://www.thirdgen.org/forums/whee...-question.html
pic of rims front to back switch

 

Thinking of doing same thing. Switching the wheels front to rear but everything I read says they will still rub LS1 brakes.............so still need a spacer.

 

Yes, from what I've been told GTA rims will still need an 1/8" spacer with LS1 front brakes. As I understand it this 1/8" spacer is needed with the front rims upfront or even if you switch the rears up to the front. I've read that with the LS1 brakes the hat adds .3" to the front offset. That .3" offset plus the 1/8" spacer will push the front wheels out approx. 1/2". That 1/2" offset from the spacer and hat can be taken back to 0, if you switch the front rims to the back and vise versa. So my plan is to go with LS1 brakes use an 1/8" spacer and switch front and rear rims.

EDIT-
I just picked up the LS1 brake parts from the local guy selling them. I measured the thickness of the hub he machined down. It's 1/2" thick so looks like I won't need the additional spacer.

 

Bet you will still need it.............how much for the parts ?

 

No I shouldn't need it with the 1/2" hub. I got a good deal $210 for everything but rotors.

 

What do you mean a 1/2" thick hub? Sorry, I'm not following why you no longer need the spacer?

 

Exactly unless you got some type of custom one off hub you will need the spacer.

 

Rotors, calipers and carriers is all that is transferable anyway.

 

The rotor he machined down into a hub is .5" thick. I've seen that a lot of people post they are .3" thick. I'm not sure why this one is thicker but I've read that with a .3" thick "hub" or turned down rotor I'd still need an 1/8"(1.25") spacer to make the GTA rims fit. So .3" hub + a spacer of .125"= .425" to fit the GTA rims.
Being his "hub" or machined down rotor is .5" thick i'm getter then the .425"(1/8") that I have read I needed for clearance...
I think I'm correct unless you guys see something I'm missing??

The guy machined the hub so I don't know where he got it but I measured it and it is in fact .5" thick.

 

I got the Flynbye caliper bracket, modified spindles, hubs, and calipers for $210

 

That was a good deal......but a thicker hub is weird.

1LE is only option to a stock hub so I don't know what you got.

 

He painted the hubs with por15 i think so maybe that's why they are thicker?? If so I'll get a spacer if needed.

 

Its not the hub thickness that everyone is talking about. It really doesn't matter how thick the hub is, as a thicker hub would mean that the caliper would have to be spaced out further to mate with the rotor, causing the same interference problem as before. What people are talking about is the extra track width due to adding a slip on rotor. Basically you are adding track width equal to the NEW rotor hat thickness you are sliding over the hub. Most rotors (not hubs) have a thickness of about 0.3". So your wheels now stick out 0.3" further than before. The extra thickness is due to the new rotor, not the hub. Hubs should be at least 0.5" thick. I suspect you have nothing out of the ordinary and will still need the spacer.

 

would you guys know what length(size) wheel studs I would need with this combo? The ones in the hub now seem short.

 

I have been looking into the length wheel studs I need to work with my LS1 brake upgrade and GTA rims. I found this, Dorman 610-323(54mm). Just looking to confirm this would be the correct stud for my application?
Also anyone know where I can get a 1/8" spacer?

 

I could have sworn we talked about stud length in a PM, but I can't find it now. I can take some measurements once I get home. But if I remember correctly, something like a 2 3/8" stud would work well and provide lots of thread engagement. This is with stock style closed let nuts. The part number you list is 2 1/8". I'm sure that would be ok as well.

I now buy spacers from Motorsport Tech. They are custom made to your specs. I'm sure they will be more expensive than a crappy cast off the shelf spacer though.

A cheap one at summit:

http://www.summitracing.com/parts/go...s/media/images

 

sounds good I just ordered the spacers you posted and the 2 1/8" studs

 

So what pushes the 1LE brakes out the .3 ?

No extra rotor thickness since it is one piece like the stock small one ?

 

It is just the way they were designed. The wheel mounting surface is further out with respect to the bearing locations.

 

the .3" is the thickness of the LS1 rotor slipped on top of the hub(which is the old 3rd gen rotor machined down). Being the LS1 rotor is now located on the face of the old rotor it is pushed out the distance of it's thickness .3"

 

Jet was asking about the OEM 1LE brakes, not LS1.

 

I misread the 1LE...I've got LS1 brakes stuck in my head