Dammit so I am trying to fix my brakes, and seriously considering the C7 z51 brake upgrade. Which according to peeps on LS1Tech seems to fit 17 inch wheels. EXCEPT I look at my CCW wheels and see there is a 1/2 inch "inset" bump on the inside of the barrel. I went with 17s when I got them b/c they generally fit and I thought I'd be good with them. I didn't buy the new brakes yet but man I am upset. I don't want to have to sell these (along with a set of extra tires) just to buy 18s and spend even more money.

Then run a standard C6 brake kit? Parts are cheap and someday when you move up to 18's you can swap up to the Z51 parts. Now, with that said I haven't looked at the C7 Z51 brake package so I don't know if it's much different than the C6 version.

Is this for autocross only? Or are you doing track events too? (I forget).

https://ls1tech.com/forums/suspension-brake...ined-video.html

The reason I was looking at this is they are practically 100% bolt on with no hub cutting (just enlarging the current holes, I am OK with that). I am really averse to cutting the spindle and really do not want to sandwich another plate into the 4 hub bolts. So the C7 caliper looked like a great option.

I just AX these days. Honestly C7s could be overkill. But I am still waiting on replacement new stock size calipers to fix my frozen caliper(s).

It's true, CCW wheels with a bump inside don't fit. I feel gypped by ccw. They even asked if I wanted to use "big brakes" in the future and I said yeah. So they make wheels that don't fit big brakes.

Do you really need the big brakes for autocross? I ask because I've never had issues with stock F-body brakes, and I've autocrossed everything from 2nd- through 4th-Gen cars. Granted, our 3rd Gen stock class car was a 1LE, but our CP car actually has smaller brakes than what it had from the factory, and I can still have enough brake to lock up hot slicks on concrete, and have had zero issues with brake fade. Granted, the car is 2800#, but it's a 2-driver car, and we run in Houston summers on some pretty big courses.

So are you needing big brakes, or figured it was the way to go since you are trying to fix the other brake issue and figured why not?

I'm very fast on stock brakes with the right pads. So, no I guess right now I don't "need" different brakes. But, it would be nice to have a little more braking confidence, out on the street, or at AX. So this whole ordeal had me thinking and planning. And boy the brakes on my friend's C7 are DARN good. Would be great to go in a little deeper and not wonder if my mushy pedal is gonna hold up.

I blame myself 1% for not going to 18s when I got these rims 2 years ago. But how was I supposed to know all 3-pc wheels have a giant inset on them?

You don't need bigger brakes for a good pedal. The limit as to how deep you can brake into a corner is limited by tire grip, not by brake rotor size*.

* On most cars on most SCCA legal autocross courses

I’m 50/50 on your situation. Yeah, stock brakes with good pads are capable (I never felt that way), but upgrading to a wilwood race kit was the best thing I have ever done for the car. Confidence inspiring brakes, that require little to no maintenance and the consumables last a million times longer. I was constantly replacing parts when I ran stock brakes (spread calipers, thin pads that didn’t last, junk rotors.)

I know you were looking at the C7 stuff as a budget upgrade, but I know wilwood makes lots that would fit your wheels. Yes, much more expensive but worth it in my opinion.

A fixed caliper upgrade might give hm the pedal feel he wants (if wheel bearings are in good shape) and a race caliper that uses thick race pads could reduce servicing requirements, but a bigger rotor than a stock LS1 12" rotor isn't needed for autocross, and will only slow the car down by increasing unsprung rotating weight. If this is a dual purpose track/AX car, then bigger brakes might certainly be worth it, but for AX only, a bigger rotor gives you nothing in this application.

So bigger isn’t better...ummm

But hasn't anyone else driven in a Mitsubishi Evo, or C7, etc with GOOD BRAKES. Man it puts the brakes on Fbodies to shame. The pedal on my car has almost always been rather mushy. I think for a few months when I had a new MC and new Carbotech pads I had a good brake feel. My friend's Ford Focus seems to stop harder than my car (I realize its probably lighter).
Though, of course I've had 2 FTDs last year so really, who needs to slow down? ;-) I drove a friends CAM-C car with C5 brakes, and it felt no better than my car. Pedal inconsistent- sometimes firm, sometimes mushy, depending on the last corner I took, or apparent engine speed.
My hubs are now good (xtracker C5 hubs on adapters). I'd love to just have confidence they will always have the same feel for each corner.

None of those cars have a semi-floating solid axle that might be cause pad knockback in the rear during hard cornering.



I can't tell if you are being sarcastic or are disagreeing with me. A bigger rotor provides two things: more mass to absorb heat during braking, and increased leverage for the caliper. At autocross, you aren't putting much energy into the brakes: there are no 150 mph->20 mph braking zones, and the stock f-body 12" rotor with good pads can lock even the stickiest tire.

Bigger is better *for a track day where you need the mass*, but smaller is better for autocross, where you don't need the mass and want to keep unsprung, rotating weigh to a minimum.

+1 on Chad's reply. In an autocross situation, lightness matters, as long as it gets the job done. This has been serving us well for more than 3 years of 2-driver, once a month Regional events:



But I'd not want to depend on them on highway or road course driving. If Chris is considering road course events, or still drives the car on the street, especially with a stock weight car, I'd not recommend those, but they ARE (without the scalloped rotors) recommended for drag race use. But if you're going to spend the money on upgrades, bigger, more mass brakes are usually a good compromise over anything different. Going lighter can compromise braking performance some.

I'm gonna do it. C7 brakes and now I get to buy new 18 inch wheels.Yeah the car sees as much street use as AX (hey if it ever stops raining in PA). So although I really like having lightness in the car, better stopping (for deer, bears, other dumb drivers) is just as high of a priority.

Anyone want some 17 x 11 CCWs and/or some 315 hoosiers?

18" wheels are where it is at these days, no good wide street tires in the smaller sizes, however the car will not stop any better in traffic for a 1 time stop with C7 brakes than it would with stock brakes.