I am considering a brake upgrade. Are there any larger (used) will brakes bolt on to my c4 convertible base?
I'm hoping to get some brakes that were OEM to another car, or generation, etc so they are inexpensive.

I'd like to do all 4 if possible.

If no bolt on, what about with a readily available adaptor?

 

If you do not already have the J55 option (13" fronts) that would be one way to go. IIRC they were made standard in the last couple years of the C4's so parts are available.

 

Hmm I'm really new to this platform, so how do I tell? Rotors would be 13"? What would they be if not?
and would this bolt on?

 

Standard rotors are 12" and everything bolts on. You need the calipers as well because the rotors are thicker on the J55. J55 is fronts only.

 

Find the sticker that has the 3 digit RPO codes. If no J55, then you don't have them. This is mine, you can see the J55 option.

https://www.corvetteforum.com/forums...e-upgrade.html

 

The cheapest and easiest brake upgrade is almost always steel braided brake lines. The rubber ones flex and swell when you push on the pedal which means less braking power. Simply changing over to braided lines is like $100 and you'll notice a night a day difference in power and feel immediately. They're like $100 for a set online anywhere.

I didn't realize the difference until I started riding sport motorcycles and it quickly became the very first thing I did to every bike I had from then once i felt the difference. Total game changer.

After that thrown on a pair of new pads and some drilled/slotted rotors. They're $160 shipped for the zinc coated ones that don't get rusty on Amazon right now front and back shipped for the C4. While you've got the calipers off swapping on the rotors pull the clips off the calipers and clean them with a tooth brush and clean up any crap on the pistons. At 30 years old even low mileage calipers need some love. Grease them real good and make sure the calipers slide in and out nicely.

Some fresh fluid when you reconnect all of them.

Your brakes have just improved MASSIVELY over what you had.

If you're still not happy with the stock calipers, you can order c5 OEM calipers set front and back in a kit for about $700 shipped off Ebay right now. It comes with OEM c5 rebuilt calipers and a conversion bracket so you can mount them to your c4. You'll need a set of lines to do this upgrade so again, steel braided or your wasting most of the upgrade. Make sure you order a new BIAS SPRING so your car doesn't nose dive. The spring adjusts how much fluid the master sends to the front and back brakes when you push the pedal.

Like is mentioned above you can upgrade to 13" front rotors as well but for my money I'd go with the c5 kit/drilledslots/braidedlines and be very happy.

Sky is the limit after that. You can get some Wilco big brake kits but unless you're building a dedicated track car the c5 kit is everything you'll need for spirited driving and occasional track days.

That's my understanding of the current state of stopping c4's.

Hope this helps.

 

I pretty much agree with everything above. How do you use the car? Honestly, stock brakes are more than enough to lock the wheels once or twice, and if you autocross or engage in "spirited" driving on the road, you can just upgrade to pads that tolerate a higher heat range. Flush your fluid and use some good replacement fluid (I use the Motul 600 stuff), and you'll be golden. Most people believe that big brakes stop faster, but that's not true. Big brakes tolerate repeated hard stops better, because they absorb and shed heat faster. That makes them great for lapping a road course, but if you aren't already experiencing brake fade (pads lose grip when they get too hot), then you don't need them.

The J55 upgrade is nice if you can get it cheap (if you don't already have it). There are lots of C4s in junkyards that have them (all 96 C4s have them, for example), or you can buy AC Delco reman calipers from Rockauto for about $100/pr and Centric rotors for about another $80-90/pr. The next step is really going to be a serious big-brake setup, with fixed calipers and floating rotors. I have a nice Wilwood setup with 6-piston calipers and good rotors with aluminum hats for track work. But I don't use them on the street or at autocross. One disadvantage is that my stock sawblade wheels don't fit over them. If you don't track your car, I doubt you need this kind of expensive setup.

 

No, no, no, NO.

Dtainless brake lines will Not improve your performance any. They may improve feel, but that's only because they have new rubber in them VS old rubber in your existing hoses. Stainless lines also have much thinner rubber, meaning they will degrade faster. The stainless is only there to protect against laceration on the track.

C5 calipers are almost the same size as c4 j55 brakes, and require custom brackets to mount. C4 j55 you only need to swap the rotors and calipers with holders, no need for an extra bracket.

​​​​Yout stopping distance is most closely related to your pads​​​​​​, the rotors are basically a wear surface and that's all. Drilled and slotted rotors look cool, but often perform worse and crack easier.

Larger brake calipers main benefit is they typically fit larger rotors, which gives you increased thermal capacity. THIS DOES NOT MATTER ON THE STREET. It doesn't even matter in autocross! Only when doing laps at a race track will you notice this.

If you're just driving the car around town, get new rubber hoses, New pads, clean up your existing calipersband maybe paint them. If you plan to track, we will need to know more about frequency, how fast you are, etc before a true recommendation can be made.

 

I take it you've never learned the concept of leverage. The further away from the center the pad is placed, the more effective it will be at slowing down the wheel.
Torque = Force * Distance. Increase the distance, even with the exact same pads/calipers, and you increase the braking torque.
Yes, heat reduction is a massive benefit, certainly not the main benefit. As you said, the thermal capacity doesn't matter at all on the street. You'll never notice it.
You WILL notice the improved braking from a larger rotor on the street.

 

I think doing a C5 upgrade is easier/cheaper than the J55 upgrade at this point. Finding the calipers and brackets for the J55 isn't as easy as it used to be.
The C5 calipers are also a superior caliper.

 

For me, having a non J55-car, the choice to go with the C5 brake upgrade was fairly easy. Install was a bit fiddly but easy enough to manage by my own.
Found a decent used set, changed every gasket and refurbished the calipers. Paired that with stoptech rotors and carbotech xp10 pads and a brake bias spring. The brake bias spring was a PITA to change in my car though.
The difference is huge. Both in feeling, may be subjective, and stopping power. My car is not a daily driver so I don´t mind the squealing and dusting from the pads.

 

I know all about leverage. What I'm saying is that you're not going to notice the difference between topping in 105 feet with larger brakes vs 107 feet with standard size brakes, unless what you're trying to not hit is 2 feet closer to you than you'd like. And that it's WAY more effective to increase your stopping ability with a pad change, plus you'll get thermal efficiency benefit form that, and it's WAY cheaper.

Food for thought, the C6 z51 brakes and rotors are MUCH smaller than the C6GS, the rotors are 13.4" on the z51 vs 14.0 on the GS, plus you get ferodo pads, and 6 piston front calipers. 60 to stopping on the two? 110ft for the z51, 112ft for the GS. Granted, the GS is a little heavier, but the reality is that the brake upgrade was mainly for thermal capacity. FWIW, the Z06 with the same brakes as the GS, 104 feet. It's also a good bit lighter than the z51 car.

 

I went with C5 from the stock 86's Girlings, and it was a night day difference. J55 didn't become available until later. You also need wheels that will clear the systems, not all 17" wheels will clear C5 brakes.

SS lines are a fine upgrade for feel, and a DRM Brake Bias spring is something that should be done after you upgrade to a larger front like J55 or C5.

Picking a good pad is also very important, but make sure you get one for street use, don't try mixed use pads on a daily driven car.

 

I haven't looked for J55 stuff in a long time, as my car came with the calipers and brackets in a box to go on. I won't argue the C5 calipers aren't better, they're slightly better. The c6 calipers too, are slightly better. The C6Z/GS calipers, are a lot better, and they LOOK great too.

If J55 brakes are harder to find, then it becomes a price thing. C5, C6 are likely similar in performance, I doubt there's a 10% improvement between C4 J55s and C6 brakes, with C5s falling in the middle. If you've got the funds, C6Z brakes are they way to go, but they're significantly more expensive, and require different wheels.

Base C7 calipers would fit as a good in between, they're nicer looking and better than base C6 calipers, but are cheaper than C6Z brakes. I just don't know of anyone making brackets to convert them. Then you've got the parking brake situation to think about.

 

The J55 stuff is a lot harder to find now.
I paid $125 for my C5 calipers and brackets from Facebook Marketplace.
Paid $150 for the adapter brackets.
Then ordered new PowerStop Z26 rotors/pads while they were on sale (CHEAP) from Advance Auto.
Topped it off with new stainless lines up front.

I have about $500 in C5 conversion and that includes upgraded rotors/pads.
My car only weighs 2600 lbs with me in it. It takes minimal brake pressure top stop during spirited driving, and the feel is great.

 

I went the cheap route of just going to RockAuto and ordering four discs, calipers and pads. I got rebuilt calipers, drilled and slotted rotors and Stainless steel brake hoses. It was less than $400 for all of it. I do have the 12" brake discs that came on my 1988 Z52 Corvette. I also replaced the brake fluid with a Dot 4 synthetic Brake Fluid. End result is I have "good" brakes but the rotors being drilled takes some getting used to. They can be a bit noisier than the standard rotors when braking hard while "bedding in" the pads.

I ordered a set of aftermarket drilled slotted (AMAZON) rotors for our 2011 Camaro and had to replace one do to a badly cut rotor with a high spot on it. They sent me a replacement set of discs but I had to pay to have them installed again.

I also agree that for the money the best thing you can do to your brake system is to get rid of the rubber hoses between the brake system and the calipers. The difference in "Feel" with the SS hoses is so much better than the stock hoses that swell every time you hit the brakes. The older they are the more they swell frequently. Classic Tubing makes them if you want to look. Be very careful to be absolutely sure that your new SS brake hose replacements are D.O.T. approved. There are many now available that are not DOT approved, in an accident they might use this to not have to pay since you were using non-DOT approved parts on the U.S. Highways. Don't buy them unless you are sure they are approved.

It is true however that new brake hoses will not make your Corvette go any faster, stop faster maybe but definitely not go faster. I am picky about having good brakes on every car I drive. Making a car stop controllably and quickly is the ticket here.
If I want to "Go" fast then I better be able to "Stop" even faster.

Best regards,
Chris

 

Okay, there's a bunch of advice in this thread that has no relevance to the OP's question. My first question: What year car? Lots of "psychic" advice here, but the OP hasn't even put this info in his Personal Profile info!

How is a "Brake Upgrade" measured? Shorter stopping distance? Lower pedal effort? Firmer pedal? Better fade resistance? Brake pad or rotor life? Minimal brake pad dust on your wheels? No noise? Or what?

This will change the feel of the brake pedal, but stopping distance will be the same. If you push the brake pedal at 100 lbs, the hydraulic fluid pressure in the calipers will be the same, so the car will stop the same.

YIKES!!! NEVER PUT ANY GREASE ON YOUR CALIPER PISTONS!!!

This bias spring has nothing to do with "nose dive" That's a function of the suspension geometry and the CG of the car

That's true, and that's how the balance of the front-to-rear braking is optimized, so you get the full braking from both the front and the rear during maximum braking.

True, true, true.

If you can make your tires "chirp" during a fast stop, none of these things will make you stop faster. If you want to stop faster, and you don't do road races, you'll need "stickier" tires!

 

Quote:

Originally Posted by Hot Rod Roy

This will change the feel of the brake pedal, but stopping distance will be the same. If you push the brake pedal at 100 lbs, the hydraulic fluid pressure in the calipers will be the same, so the car will stop the same.

Yeah that isn't true one bit. If the hose swells, you're changing the final volume of compression and you end up with less pressure. It would be like your combustion chamber swelling on the compression stroke.

 

I take it you've never learned the concept of tire grip. Leverage is a thing, yeah. However, if your stock brakes can already lock up the tires, then more leverage doesn't do a damn thing to improve stopping distances: your tires are the one and only limiting factor at that point. And all stock cars can lock their brakes once or twice in rapid succession, at least. If yours can't, your car is broken and you need to address that before you drive it again! As you can see in my avatar pic, I autocross with a 396 LT4 on very sticky 315-width tires with 11" wheels front and rear (tires are either BFG Rival S or Hoosier A7). So I have a metric ****-ton more grip than a stock 96 Corvette. My stock J55 brakes with decidedly unfancy Powerstop pads and Centric rotors can still easily lock up the brakes any time during a run. You can't stop any faster than that. More leverage will only make it easier to lock the brakes.

 

Hopefully nobody is going fast on bald original tires. Introducting poor traction as a variable is a bad point.
If I introduced maximum traction via road racing slicks, then the argument would weigh heavily in my favor.
Available traction would exceed available braking force of the J55 brakes.

It is true that up to a point, maximum clamping capacity is going to exceed traction capability.
So then you weigh other benefits, like better rotor heat dissipation, reduced pedal effort, larger pad surface area, all of which increase both pad and rotor life and make braking easier.