IDriveA95Z28

Well i made up mind. i am going to stick with the LT1 and build it to 500ish HP. i may go to a supercharger later later later later down the road but thats like 5-7000 bucks. Anyways, I recently got new tires. I got Falken Ziex 245 50R16 now id assume it would be smart to get new brakes before getting more power?? i was looking toward the drilled and slotted rotter path buuttt....i dont really know what to do for the first upgrade to be honest. i wanna run either a 2.5" exhuast or 3" exhuast. i dont know what type of headers to get i have looked and looked. what is it that i need to think about when looking at headers? also i dont know what to do with cat. i know what sound i want i just cant explain it id like a really nice idle sound, and if im correct that comes from the camshaft?? i know i ask A LOT of questions and im sorry if bug you but im just trying to understand this, cause right now i dont know anything really.....im a high school kid that loves cars. i am 17 i turn 18 in april. i go to school for diesel mechanics and will be persuing it as a carrer. i work currently but on the weekends buuuutt i get 14$ an hour so i get good pay. i want to be the guy that loves cars and knows what he is talking about. id like to know what your suggestions are for a upgrade path. i have a lot of dreams but i need someone to help me find the right path. i have never raced to be honest. fastest i have ever gone is 110mph. i dont race because my car has issues and i dont ever see people that will race or if i do i am in traffic....but i want a car i can drive on the weekends. but has the ability to whoop ***. i know ill have to buy a cheap car as this will become a project car and wont be ideal to drive daily anymore. like i like high horsepower cars but i think a 500-600hp street car will do i will also most likly be taking it to the drag strip...so a mixed street drag car. i want to keep the body and interior how it is...if posssible. anyways, Thanks for any and all suggestions!!!

Chimera96

Jordan

500-600 HP....That is not a cheap motor. Assuming you mean "rear wheel" HP ....When you get in that neighborhood you are talking big $ and you really don't have a daily driver street car anymore. You will need significant driveline and suspension upgrades to get that power to the ground. Also a long list of "supporting mods".

Might want to scale down the HP goal.

You're in high school so I suspect your wallet is not very thick. Come up with a realistic budget and build from there. Your car is 20+ years old and if the motor has 150k+ miles you really need to rebuild it to make any decent power and have reliability. Your automatic will need attention quickly once your motor starts making more power than stock.

Some good mods that can later transfer to a "built" motor are:

lower rear gears
2800-3200 stall TC
Headers
1:6 RR
Valve Springs
PCM tune

JakeRobb

Hi! You're in luck; my wife isn't home tonight and my daughter is in bed, so I have lots of time to help you out.

My apologies -- I'm a bit of a spelling/grammar ****, and so while I read through your questions as quoted below, I fixed some things. It makes it easier for me to read and understand what you've written. I also reorganized the parts to help me arrange my thoughts in response. Hope you don't mind!

I love people that ask questions and acknowledge what they don't know. I'm glad you want to learn! You've chosen a great platform to learn on -- it's somewhat modern, but no so much so that it's difficult to learn and work on. Your education as a diesel mechanic will provide a solid foundation of skills and knowledge to work from, too.

My car is a 2002, and the fourth-gen ('93-02) Camaro underwent some fairly major changes in '98. I know a fair amount about '93-97 cars like yours, but I'm sure I'll get a thing or two wrong. Hopefully one of the LT1 experts will chime in and correct me.

All of that being said, let's start with what you want to get out of the car:

Racing is enormous fun, and a great way to get to know your vehicle. Please keep it safe on the streets. There's no need for you to get arrested or your car impounded. The occasional stoplight blast is okay, but please be safe. F-bodies arrive alive!

350 horsepower at the rear wheels is enough to beat 99.99% of cars you'll see on the road.

There are lots of great ways to get into racing. You should find out what you enjoy the most. Some guys just love the thrill of acceleration, and so they spend lots of time at the dragstrip. Other guys love high-performance turning and braking, too. Autocross is a great way to get started on that, and you can build up to HPDE and full-on road racing if you find that you like it. None of these things require a fast car or any upgrades. Just find a local racing club, buy a helmet, and get started!

Can you elaborate on "my car has issues"? The particular issues might lead to slightly different advice going forward.

500hp is a VERY optimistic goal for a naturally aspirated (that means not turbocharged or supercharged) LT1. It's also a BUNCH of power for street use. I suggest you build power incrementally at first. This will let you ease into learning how to handle all of that power. There are way too many videos online of inexperienced drivers putting high-powered cars into ditches, guardrails, and trees. Take your time on this!

If you want a 500hp LT1 that isn't just awful to drive on the street, when the time comes that you decide you're ready for that power level, you probably want do that with a supercharger (or turbocharger). Almost all of the mods you'll do in the meantime will also be in support of the supercharger when the time comes, so you're not wasting anything with this approach.

The mods Chimera96 listed above would be a good place to start. Along with those, I'd look into a cat-back exhaust (Magnaflow is a great budget option, but there are tons of considerations here which I discuss below), and a cold-air intake. Also, look into a set of subframe connectors.

That's a budget tire. It'll serve you fine for now, but the more expensive offerings are a significant upgrade. As your finances get more flexible, keep this in mind.

Related: one of the best upgrades I ever did for my car was to upgrade to 17x9" wheels. Z28s come stock with 16x8" wheels. This increases the tire size to 275/40R17. There's a better selection of performance tires in that size; plus, it looks better, offers a bunch of additional grip, and makes more room for brake upgrades. You can go bigger than 17" if you want. 18" has an even better tire selection. I'd avoid 19" or bigger -- they look terrible IMO, and there's a BIG jump in tire cost.

Speaking of brake upgrades:
Drilled/slotted rotors are an appearance upgrade. With modern pads, they do nothing to help performance. On a road course where you're actually working the brakes hard, they shorten the life of your brake pads.

If you really want better brakes (which I encourage -- especially if you think you might end up getting into HPDE stuff), you have a handful of options. Everything starts with swapping out your spindles for the 98-02 versions, which you can get for as little as $40 each or as much as $220. I'd recommend the ~$110 Timken at a minimum; personally, I'd pony up for the top-of-the-line ACDelco. Wheel hubs (as well as the rest of the brake system) are a critical part that I wouldn't cheap out on.

From there, your options are:

stock 98-02 brakes:
12" straight-vane rotor
dual-piston sliding caliper
mediocre aftermarket rotor offering
decent aftermarket pad offering
fits under your stock wheels
all the parts you need to match a stock '98-02 Z28 for ~$225; you can pay less for off-brand stuff

C5/C6 Corvette brakes:
13" directional vane rotor
dual-piston sliding caliper
optional: red C5 Z06 calipers (functionally the same, they just look cool)
great aftermarket for rotors and pads
requires 17" wheels and an adapter bracket
figure $450 minimum for the parts you'll need; you can choose to spend more for better pads/rotors/calipers; don't forget to account for new wheels and tires too

'04-07 CTS-V / C6 Z06 brakes:
14" directional vane rotor
four-piston (CTS) or six-piston (Z06) two-piece fixed caliper
requires wheel spacers or a different offset; 18" wheels required
requires caliper bracket adapter and other hardware
figure $900 minimum for the parts you'll need; you can choose to spend more for better pads/rotors/calipers; don't forget to account for new wheels and tires too

StopTech
13" directional vane two-piece rotor
four-piston two-piece fixed caliper
fits under most 17" wheels
$1800 gets you ALL of the parts you need (except wheels that clear and tires to fit them)

Baer Track4
13" directional vane rotor
four-piston two-piece fixed caliper
uses 98-02 Camaro pads
fits under most 17" wheels
$1395 gets you ALL of the parts you need (except wheels that clear and tires to fit them)

Baer 13" Pro+
13" directional vane two-piece rotor
six-piston two-piece fixed caliper
uses C5/C6 Corvette pads
$1945 gets you ALL of the parts you need (except wheels that clear and tires to fit them)

Baer 14" Pro+
14" directional vane two-piece rotor
six-piston two-piece fixed caliper
uses C5/C6 Corvette pads
fits under most 18" wheels
$1995 gets you ALL of the parts you need (except wheels that clear and tires to fit them)

Baer 14" Extreme+
14" directional vane two-piece rotor
six-piston monoblock caliper
uses "D1247" pads -- a popular size among significant brake upgrades, with a wide aftermarket
fits under most 18" wheels
$3395 gets you ALL of the parts you need (except wheels that clear and tires to fit them)
There are a bunch of extra-cost upgrade options on top of the $3395 starting point. For example, for an extra $350 + a 19" wheel requirement, you can have 15" rotors!

For reference, your stock system:
11" rotor
single-piston sliding caliper
fits under most 16" wheels

For each of the factory upgrades, plan on supplying your own flexible brake lines, crush washers, and possibly other minor hardware. This should total less than $100. The Baer and Stoptech kits come with all of that stuff.

For ALL of the upgrade options, remember to include 98-02 spindles in your budget, as discussed above.

I just ordered the Baer 13" Pro+ kit for my '02 Z28. I found a sale and got it for ~$1500! (This recent purchase is why my knowledge on this subject is so detailed.)

For you, what I'd recommend is to do the '98-02 upgrade for now. Most of the cost is in the spindle upgrade, and you'll need that as a basis for any future upgrades as well. The '98-02 stock brakes are good enough for most cases. I am upgrading mine because I attended an HPDE at a track that is notoriously hard on brakes. I went with a co-driver, which meant the car was doing 40-minute sessions instead of the usual 20. The brakes performed admirably, right up until they failed quite catastrophically. I need new pads, rotors, and calipers -- so, what better time is there to upgrade to something that can handle that kind of abuse?

There are "longtube" and "shorty" headers. Your profile says you're in Washington, which has inspections. If Washington is among the stricter states, longtube headers might not be an option because they relocate the cats. Relocating the cats is technically illegal under federal law, but not all states' inspection processes are stringent enough to catch you. Ask around among your local car enthusiasts to find out what limitations there are. You might need to limit yourself to shorties.

A popular brand for shorty LT1 headers is BBK. That's all I know.

Most headers that will fit your LT1 have 3" collectors, so you might as well go with a full 3" system. You'll also want a Y-pipe (or you can convert to true duals, in which case you can opt for an X-pipe or an H pipe instead). There are "catted" Y-pipes and "off road" Y-pipes (ORY's). , so you might not be able to get away with no cats. Again, ask around. If you need to keep the cats, keep in mind that a catted Y tends to cost about $300-500 more than an equivalent ORY.

The most popular LT1 longtube headers are from Pacesetter, because they're cheap and they get the job done. You can get a set with an ORY for under $400. A popular longtube upgrade option is from Hooker -- these are in the $600 ballpark. The top of the line option would be anything made of stainless steel. Last I knew, Kooks was the brand of choice, but there are some other options. These tend to cost about $2000 with Y-pipe.

As you go more expensive, the features you're getting are improvements in precision manufacturing, durability, heat management, and scavenging. I've heard stories about guys who bought Pacesetter headers and they didn't fit without modification; that never happens with Kooks. The mild steel Pacesetters will eventually turn rusty, whereas the stainless steel Kooks will stay shiny and get a sweet looking heat-coloration to them after a few uses. Stainless steel also offers better insulating properties, so that that heat from your exhaust is kept inside the pipes, rather than heating up your engine bay. Heating up your engine bay is bad for a number of reasons -- you lose horsepower, you can melt nearby parts, you can cause nearby sensors and electronics to fail, you can cause knock, etc. And finally, scavenging: this is a neat effect you get when all of the primary tubes (the smaller tubes that come off of each cylinder and join together at the collector) are the same length. When that's the case, the "pulses" of exhaust gas can actually help to "pull" the pulses behind them through the exhaust system. This means more power, lower heat, better sound, etc.

Regarding sound: there are a handful of major factors, and yes -- your choice of camshaft is a major one. There used to be a website called lt1sounds.com where people could post their exhaust sounds and it was categorized by different types of headers, cat-backs, cams, etc, but it's gone now -- so just get on YouTube and start searching until you find what you like.

Your choice of muffler will have the biggest impact on how loud the exhaust is, and how boomy/raspy/drone-y it is. Keeping the catalytic converter(s) reduces volume and rasp significantly. Headers change the character of the sound in various ways, but there are too many variables after them and so I don't really have it figured out.

Your choice of camshaft will affect how "lopey" the car is at idle. Along with heads and other valvetrain components, it will also affect your redline, how much power you make, and where in the rev range you make that power. A very aggressive cam will give you a very rough idle (which you can mitigate with a high idle RPM) and poor drivability.

You're very welcome! I hope I've been helpful. Please feel free to ask followup questions!

Have a great day, and welcome to CamaroZ28.com!

Fatdog2

JakeRobb.This is one of the best posts I've ever seen.I hope it becomes a sticky.I really enjoyed reading your post.It lays it on the table.Great write-up.Always great to see your posts(and others).My02.

Injuneer

Still need to know if the OP wants his 500 HP at the wheels (expensive and hard to do N/A) or at the flywheel (doable with ported stock heads, by LE of AI, with matching cam and other upgrades).

IDriveA95Z28

Yes EXACTLY...i told everyone i should probably rebuild the motor. But everyone said no. You are the first to say yes. I never relized that 500hp is a lot for a street car. Cause if you look at the new maros makeing 455hp+ but then thats a 50000+ dollar car. Would 375hp be reasonable?

Injuneer

375 HP at the rear wheels, or at the flywheel of the engine? Are you aware of the difference between those two HP ratings?

Chimera96

What I said is adding heads/cam to make more power on a 150k mi motor, for example, IMHO is not the best because the motor is going to be taxed with higher revs on what is a well used bottom end. So if it were me I would not do H/C on a 20 year old motor with high mileage.

I would do the list of mods I noted and just drive the car. It could go another 100k mi

When your check book has the $ and you have a better understanding of engine modifications then build a motor to achieve the goals..

"Freshing up" a stock bottom end with a crank polish or grind and .030 over bore with new pistons, resize the stock rods with ARP fasteners and new cam, rod & main bearings will get you a "fresh & new" bottom end and deal with a H/C & tune quite nicely

375 RWHP is easily achieved with a H/C package and be very street able for a DD

IDriveA95Z28

Hey sorry i just saw this! Thank you for the advice! This us great. I will respond with more questions when i get home.

IDriveA95Z28

Okay so when you asked about if i like the acceleration and such, i do like quick acceleration but i LOVE speeding like taking turns and such! i guess i should lean towards autocross or road racing events....or whatever it is. You just really got me thinking about what i really wanted. so drop all the power talk for now. What do i need to know about grip, cornering, suspention, everything i should know. i will be looking into it myself. cause im aware that you dont really need a lot of power for autocross.....haha well first off is autocross the one where you try to complete the track at your fastest time?

JakeRobb

The single most important thing in terms of grip and cornering is driver skill. Gaining experience (by participating in autocrosses!) is going to help you more than any mod. Watch this:


After that is tires. Get good tires. They're expensive, and they're worth it. Summer tires are hugely better than all-seasons, and there are dedicated racing tires where are hugely better still. Tires are the part that makes contact with the road, and they'll nearly always be the limiting factor with respect to how much grip you have.

After that is predictability. You want the car to behave consistently so that you know how it's going to respond to your inputs. One big factor here is stiffness. If you read car reviews, you frequently hear that a new generation of car X is 40% stiffer than the previous generation. Your Camaro's chassis isn't terribly stiff.

The single biggest thing you can do to help is to install subframe connectors. I recommend three-point bolt-in connectors (here's what I have). These will really cancel out a ton of body flex in your car. You'll notice the biggest difference when driving over uneven roads, rough railroad crossings, etc. It also helps with the notorious F-body squeaks and rattles.

Once the body is stiff, you can think about stiffening the suspension components. Control arms, panhard rods, etc -- the factory versions of these are all stamped steel and can flex quite easily. BMR and UMI both sell a variety of tubular or boxed steel upgrades which, in general, are both lighter and far stiffer than the factory pieces. I haven't personally gotten around to these upgrades myself.

The factory shocks, springs, and anti-roll bars on our cars aren't great for racing. I haven't gotten around to upgrading mine yet, and so I don't have a lot of info here, but the most important thing to know is that they should be chosen based on what you want out of the car and matched to each other. For best results, you should lean on the advice of an expert to match them up. You can spend anywhere from a few hundred to a few thousand, but for the most part the extra cost gets you more adjustability rather than more performance. Sam Strano has successfully raced (mostly autocross) a 4th-gen Camaro for years, and he runs a website (stranoparts.com) that sells lots of good stuff in this department. When you're ready to spend money on suspension, call Sam (seriously -- pick up your phone and speak with him), tell him what you want from your car, and buy whatever he recommends.

I've done a handful of autocrosses over the years, in my Camaro as well as a few cars I owned previously. An autocross can be fun in ANY car. It's just you on the course, trying to set the best time you can from start to finish. Sometimes these are held on real racetracks, but usually they're held in large parking lots, with the course laid out with traffic cones. A run generally lasts 40-90 seconds, and cars are divided into classes so that you can compare your time against people working with comparable equipment. You'll get 3-6 attempts. I had just as much fun doing this in a 110hp Civic with automatic transmission as I did in my ~375hp Camaro. You generally pay $30-50 to participate in one, and you generally volunteer your time as a "corner worker" (someone who picks up cones that get knocked down and provides other assistance) for a portion of the day.

Last summer I participated in my first HPDE (high performance driving event). In an HPDE, you race with several other cars on track at the same time, but passing is restricted to make things safer. There are no lap times (unless you measure them yourself), no winner, no prizes -- just driving fast for fun, generally 20-minutes at a time, as many laps as you can squeeze in to that time. It costs a fair bit more (I think I paid $125) but you don't have to work and you get a ton more time behind the wheel. It was by far the most fun I've ever had. I brought a coworker with racing experience with me as a codriver (we took turns driving 20-minute sessions). Here's a video of my first session, with my coworker in the passenger seat coaching me:
HPDE's extra fun and track time come with some extra costs beyond what you have to pay. You will almost certainly burn through a set of tires and a set of brake pads. You will consume a LOT of fuel. And you just might break something!

For my event last summer, the car was on track for five 20-minute sessions. I'd estimate we burned 20 gallons of fuel, not counting the ~200 mile round trip to the racetrack. At last summer's $4/gal prices, that's easily $100. My tires had maybe 30% tread remaining and were toast when we were done. I generally spend $800-1000 on a set of tires, so let's call that $300 worth of tires. My front brake pads were two weeks old and were completely used up by the end of the day. There's another $100. With the $125 admission, that means I spent over $600 that day.

And that's before you take into account that I totally destroyed my brakes. Remember in my earlier post when I said I had just ordered a new set of brakes? That's because the stock 98-02 brakes were not up to the task of slowing the car over and over and over again at this track (which is a notorious brake killer of a track). Here's a photo that shows my rotors glowing red-hot (over 900° F):



And these photos show my front brake calipers after I got home. The dust boots were destroyed.



And here are the brake pads:


So, if I'm going to keep doing HPDEs and ever want to do so at a track that's hard on brakes, I'm going to need a brake system that can handle more heat. Any of the upgrade options I listed above would give that. I chose the one that best balanced with my available budget.

Rewinding a bit, see the photo above with the glowing brakes? Look how much suspension compression there is in front, and how much extension there is in back. This is called weight transfer, and it's expected under heavy braking. Weight transfer is controlled by your suspension, and as you can see the stock suspension allows quite a bit of it. I would estimate that at least 80% of the car's weight is on the front tires in that photo. That means that less than 20% of the weight is on the rear tires, which means that the rear tires can contribute less than 20% to the overall grip available. Weight transfer from back to front is called "dive." Weight transfer also occurs in corners, from side to side. This is called "roll," and the outside tires will bear a larger portion of the weight than the insides, and your overall grip is therefore reduced. Finally, there's "squat", which is the weight transfer from front to rear under acceleration.

When you upgrade your springs, your main goal is to reduce weight dive and roll (and to a lesser extent, squat). This is accomplished by choosing springs with a higher "spring rate", which is the spec that tells you how much the spring will compress under a given amount of weight. (Note that the spring rate needs in drag racing are different; I'm talking about upgrading a car with the objective of maximizing cornering and braking performance.) So when you install higher-rate springs, you reduce the amount of dive/roll/squat for a given braking/cornering/accelerating scenario. Less of those things means more overall grip, because the car's weight remains more evenly distributed over all four tires.

To minimize weight transfer, then, you would want a suspension that doesn't compress at all under any amount of weight. Right? Sure, if you only drive on perfectly clean, smooth roads and don't care about comfort at all. The compressibility of the springs is what allows the car to ride smoothly over rough roads and not transmit tons of noise, vibration, and harshness (NVH) into the body of the car and its passengers.

To minimize NVH, of course, you would want a suspension that compresses very easily. So in practice, spring choice is a balance between those two objectives, where the ideal balance varies depending on the car's intended use.

For side-to-side weight transfer, or roll, there's another component that contributes to the fight. It's called an anti-roll bar (and also sometimes called roll bar, anti-sway bar, sway bar, or stabilizer bar), and your car has one in front and one in back. Some less-performance-oriented cars have one only in front, or even none at all. This bar takes advantage of the geometry of the car's chassis components to provide resistance in situations where one side is compressed and the other is extended. It's complicated, but all you need to worry about is that a stiffer bar generally means less roll. It's important to choose anti-roll bar stiffness in concert with your shocks and springs, and to keep the front and rear well matched.

Now, let's get into shocks, which is short for shock absorbers, aka dampers. You know what happens when you hang a weight from a spring, pull on the weight, and release? This:


That's called oscillation. Oscillation in your car's suspension would be bad -- you'd hit a bump, or touch the brakes, or turn a little, and it would start everything bouncing all over the place. Every little input would perturb the system. It would be nothing short of insane. Here's a video showing a car whose rear shocks have clearly failed:

To prevent this, you add shock absorbers. They look like this:


The shock absorber's job is to provide some resistance to movement, and this is usually accomplished by having a piston that goes into a chamber of viscous (thick, like syrup) fluid that has to get pushed through a smallish hole in order to allow the piston to move. Here's a good diagram:


That's a simple design that provides equal damping (resistance) to both compression and extension (which is usually called rebound when talking about shocks). High-end performance shocks generally provide different levels of resistance to those. The most expensive performance upgrades generally have a pair of dials -- one to adjust compression damping and one to adjust rebound. If you want to get even fancier, many modern high-end performance cars have shocks use a special fluid whose viscosity can be changed by applying a magnetic field, so a computer can decide on the fly how much damping is needed, varying it hundreds of times per second.

Shock damping rates are, again, a compromise, and again they need to be matched to your springs and anti-roll bars for best results.

I'm out of time. Let me know what questions you have next!

IDriveA95Z28

Thank you so much for your help!! I recently talked to a buddy of mine who does autocross. he said for me, i should get some ride alongs to get a feel for it.

Im gonna have to hold of on this cause my car obviously needs new breaks. when i go to stop, my car bounces forward slightly till i come to a complete stop.
Money isnt an issue for say, i would just have to save up....and depending on the price, it may take a short time or a long time.

i really love the CTS V....its honestly my dream car for a daily. so i for me i think it would be really cool to have CTS V breaks on my car.....yes i relize i need new wheels, tiers, and the parts alone are 900ish bucks. so im willing to start saving now for them.

i know its highly highly highly recommended to have really good breaks, tiers, and such for these HPDE's should i just go and try to do ride alongs for now? cause im just trying to find something thats competitive and involves driving. and having to possibly get new tiers often and such isnt in my world currently...so what else is out there that im missing? i know..... car enjoyment=$$$$

just to clear some things up...i litterly bought new tiers 2 weeks ago.
also, the reason why i am always asking these obvious questions or sometimes stupid ones on here is because i dont know much about cars currently and also anything i tell my step dad (hes owned the camaro before me) he just says "dont worry about it, its just how the car is" well i notice every damn thing that goes on in my car....from the smallest noise...to the smallest feeling...hell ill even drive with now music sometimes to see if theres another new sounds or someting. i am one that simply cant go on without knowing what it is. i dont have any friends that are as into car as i am, so i cant call a buddy up and ask him to come over. so i really apperciate your guys/gals time and effort to help me, i am wanting to learn it just takes me time. i am slow at grasping concepts so may clarify sometimes.

anyways should i just replace my breaks with stock OEM ones or go up to the 98-02 brake modles for now? i also believe i need new struts and shocks...so theres that. i could name off so many things i think are wrong.

Thank you for any help!

Injuneer

In order to answer your question about replacing the brakes, you have to clarify what this means:

Do you mean the brakes feel like they are disengaging and reengaging for the entire time you are trying to stop? Or does this happen only in that last 10-feet or so? Does the "LOW TRAC" on the dash come on when this happens? Do you feel a pulsing in the brake pedal when this happens? Does the "ABS INOP" light ever come on?

Or do you mean the front of the car is bouncing up and down when you apply the brakes?

JakeRobb

I agree with Fred -- please clarify what's going on with your brakes. I wouldn't do any sort of upgrade or repair until that's diagnosed.

IDriveA95Z28

When i apply my breaks it feels like their disengaeing and re-engageing. It happens id say up most time when im slowing down from 30 miles an hour or less. No lights come on. People i have asked said it may be the one of the pistions are not fully applying maybe. The car itself isnt bouncup and down, i guess i should say when i break it feels like something is grabbing it and holding it back, then releaseing it, and it repeats this till it comes to a stop.