What to do about braking?

About two years ago i purchased an 11inch brake kit for my civic and never installed it, i got a decent deal on it without rotors (im supposed to use corrado rotors).

For a while i was worried that having an 11 inch brake kit with HPS pads and all seasons in the rain might be a little too much brake on a car that is so light.

Fast forward a year and i drove on some used RA-1s i got for cheap, (still using stock brake setup +super blue brake fluid), and my brakes felt like they were being raped. i could barely slow down from the top of second gear and the brakes felt cooked.

SO, the big question(s) is now that i recently purchased a car for daily driving duties,

1)should i go ahead and throw them on?

2)do you think ill have too much brake for street tires as my ra-1s are about to become trash?

3)are slotted rotors REALLY worth it?

4) Would i be better off just getting good pads to handle the heat, and just sell the kit or what?

thanks in advance! sorry for so many questions!

1) Sure

2) HPS pads aren't that aggressive, you'll be fine

3) not really, not with modern pad compounds

4) good pads help, a lot. Is this on the street or the track?

The car will only break as hard as you push on the pedal. ;)

well its occasionally beaten on in some deserted backroads in my area, and it used to be my DD, but now that i have another car im only going to take it on the streets when im driving to and from events or just get the urge to drive it. the bucket seat, though one of my favorite purchases, and lack of AC keep me from wanting to drive it every day.

skierd wrote: The car will only break as hard as you push on the pedal. ;)

haha that made me remember my first time on the RA-1s, i went WAY fast into a right 90 degree after the straight on this little track in camden OH and i was almost standing on the brake lifting my butt out of the seat. luckily i braked plenty... turns out i could have gone faster...

cxhb wrote: About two years ago i purchased an 11inch brake kit for my civic and never installed it, i got a decent deal on it without rotors (im supposed to use corrado rotors). For a while i was worried that having an 11 inch brake kit with HPS pads and all seasons in the rain might be a little too much brake on a car that is so light. Fast forward a year and i drove on some used RA-1s i got for cheap, (still using stock brake setup +super blue brake fluid), and my brakes felt like they were being raped. i could barely slow down from the top of second gear and the brakes felt cooked. SO, the big question(s) is now that i recently purchased a car for daily driving duties, 1)should i go ahead and throw them on? 2)do you think ill have too much brake for street tires as my ra-1s are about to become trash? 3)are slotted rotors REALLY worth it? 4) Would i be better off just getting good pads to handle the heat, and just sell the kit or what? thanks in advance! sorry for so many questions!

1) Yes.
2) No.
3) No.
4) Nah. You have the kit, put that sucker on. You don't sound like you've narrowed down where your fade is coming from. If you're overheating your rotors, glazing your pads, or boiling your fluids. Put the kit on with some nice pads, and run some high temp fluid and enjoy. Better to have overkill than not enough, in my opinion.

cxhb wrote: haha that made me remember my first time on the RA-1s, i went WAY fast into a right 90 degree after the straight on this little track in camden OH and i was almost standing on the brake lifting my butt out of the seat. luckily i braked plenty... turns out i could have gone faster...

That's what you get for racing on a kart track!

I grew up 15 miles from there, and a relative owns the joint. And I still haven't driven on that track...

skierd wrote: The car will only break as hard as you push on the pedal. ;)

That could be taken many ways, depending on the pedal and what you're doing at the time.

In reply to Kramer:

do it, its a blast. July 12th is the next event. drift/grip event. Im one of only like three grip drivers. and the only civic. so i get made fun of a fair share. but its ok. at least im out driving.

Is the kit a four-wheel setup, or front only? If it's the latter, you'll probably decrease your braking ability due to the incorrect brake balance unless you install an adjustable proportioning valve - and even then, you might not be able to bring it back.

When your brakes "felt raped", was the pedal soft or hard? That'll tell you where your fade is coming from. If you're running race tires, change over to race pads when you go to the track.

Don't think of it so much as the "amount" of braking, but think of it like the length of the lever you have to make braking torque.

For instance, lets say you have a record player spinning at 100 rpms and you want to slow it down to 50 rpms. If you put your finger on the record at half its radius, you'll find that as you add pressure, the record slows down. Let's say that at 60 rpms, the pressure you have to exert actually stops the record. Now do the same test at the outside edge. You'll find that as you add pressure, its not only easier to modulate the speed of the record, but since you have doubled the radius, you have more control over how your inputs affect the speed of the record. You might be able to slow the record to 30 rpms before stalling it, and you would have to use less force to do so.

Larger brakes simply increases the length of the lever you're using to impart braking forces. Vehicle weight plays a role in how big they need to be adequate, but other factors determine how much foot force equates to actual braking force. Brake pedal lever ratio, size of the piston of the caliper, diameter of the master cylinder bore, etc.

In general, you can't have too much braking from rotor size. You can have too much pad pressure from too much assist, or a mismatched master cylinder/caliper combo. But as a generalization I will say this. If you have 10" rotors and it takes 50 pounds of foot pressure to stop the car at a rate of X, and you then switch to 12" rotors with the accompanying alterations to calipers/master cylinder/ etc so that you still stop the car at the same rate, you have scored a bonus. You will still have the same brake pedal force required for your driving, but you will have effectively added greater braking above and beyond what you had before due to the longer lever of the larger rotor.

Of course that is extremely generalized and doesn't take into consideration the widely varying factors like rotor finish, pad compositions, etc.

Keith wrote: Is the kit a four-wheel setup, or front only? If it's the latter, you'll probably decrease your braking ability due to the incorrect brake balance unless you install an adjustable proportioning valve - and even then, you might not be able to bring it back. When your brakes "felt raped", was the pedal soft or hard? That'll tell you where your fade is coming from. If you're running race tires, change over to race pads when you go to the track.

its a front only kit. which got me thinking, i forgot to add this into the equation. i upgraded my master cylinder to a 15/16" and did a GSR rear disc brake swap three years ago. not sure if that makes any difference... the proportioning valve is stock, seeing as a cx proportioning valve is the same piece as an SI which have larger front brakes( i believe) AND disc rears just as mine do

the whole "they felt raped" meant the pedal went a tad soft, not spongy like i have air in the lines, but sank somewhat. and the car did NOT want to slow down.

In reply to curtis73:

although yes it was generalized, it was a good insight into a better understanding of the subject. thank you.

I have a 96 dx hatch into which I put the 99-00 civic si front and rear brakes and master cylinder over time. I left the portioning valve in because my research turned up several sources with solid information that all trim level the 96-00 hatches have the same portioning valve as the 99-00 si. The sedans and coupes (exempt SI) do not have the correct valve according to the info I found.

My test hill for the brakes is a 5 mile 1200' drop canyon road.

The hill with stock brakes I was out of brakes in a 1/4 mile.

when I added good front pads and ATE super blue, they jumped way up in usefulness, but were still gone halfway down the hill.

when I added rear disks and ss lines the brakes improved some more, but were still gone before the bottom of the hill. There was a bit of rear bias at this point. I kinda liked it, but in the wet downhill it was too much and the rear would step out when you did not want it too, or were not trying to make it step out. This set-up was much much better than stock. The rears would lock if severely provoked.

when I added the SI (EX) front rotors and upped the front pads to HP+ the balance came back and the car made it to the bottom of the hill with thermal capacity left. I forget the exact pads i have in the rear (Nissin metal master rings a bell) but they are nowhere near as aggressive as the HP+ in the front.

All of the above happened while on toyoTR1 195 55 14". I was not out of tire until the last setup. then I could lock everything up.

I put on Hankook rs2s in 195 60 14" and I had more tire than brake again. The car now has more brakes than I will ever be able to use on public roads. They probably would go away on a track. I should try that.

In reply to Shaun:

do you know the size of SI (EX) rotors? ar CX's the same?

cxhb wrote: In reply to Shaun: do you know the size of SI (EX) rotors? ar CX's the same?

SI EX are 10.3", everything else is 9.5".

ok, so im guessing going 11 inch and using the stock proportioning valve i SHOULD be ok.

i wonder if type r brakes are 10.3"? if they are closer to 11" then i may be able to just use a type r prop. valve...

thank you shaun.

http://honda-tech.com/showthread.php?t=1513752

Honda tech has loads of info, much of it bad. But I have been able to find lots of good info with effort put in to verify and cross check.

1) Abosolutly!!!

2) You won't have to much brake for your tire till you upgrad to HP+'s

3) No, if they were F1 would run them. It's a popularity/Cool thing. If you really want to cool your brakes down go buy some ducting. They either develop stress cracks around the holes or they are WAAAAY to overbuilt to prevent the stress cracks (aka they weigh to much).

4) You should sell the kit to me....

awebb: you're reading comprehension fails you.

slotted rotors are about keeping the glazing off the face of the pads, sort of a cheese grater kinda thing. Slots are not cross-drilled holes. Cross-drilling is not about cooling, it is about pads that gas-out as they warm up.

F1 uses carbon/kevlar/ceramic braking rotors and pads that run at much higher temperature levels, F1 also spends a lot of time and money on their cooling solutions, so please don't try to compare street car braking systems with F1 braking systems, the amount of money spent and the environment they have to function in are completely opposite of a street car.

I would suggest going and reading the braking articles that GRM has published, take the equations provided in the articles and plug in the numbers for your stock system and the modified system so that you can know what the changes will be and whether further changes are needed.