1991 Civic Si brake proportioning

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Dual-500

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I have a 91 Civic Si with mild performance upgrades. Last brake job I installed organic pads in the front brakes to reduce heat and rotor warping. It helped out, but it also unbalanced the brakes too much to the front. It's especially bad on wet streets.

So, I picked up a pair of new rotors with pads from BrakePerformance.com.

They are RB-40023 dimpled and grooved and came with pads. The pads are semi-metallic. I haven't installed them yet, but am beginning to think maybe ceramic pads would be best to properly balance the system.

I need more braking in the back. Wheels are 15x7 with Nitto NT 450 P195/50R-15 81V tires.

Any comments would be appreciated.

Thanks!

Steve
 
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:disgust1:

slotting does nothing for cooling
slotting does increase your stopping distance (ie: it takes you more distance to stop)
 
Well, then I went the right direction with things. I'll install this weekend.

My logic tells me if a system is balanced front to rear and one goes to slotted rotors from non-slotted, then stopping distance will increase. However, in this case with a system that is unbalanced and braking too much in the front, going to slotted rotors should decrease stopping distance assuming it will be closer to correctly proportioned front to rear. I know my front tires will be happier.

Thanks guys!
 
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Drilled and sloted rotors are designed to scrub the pad material down, thus keeping the pads from glazing which is only needed under racing conditions, thus wearing pads out faster.
 
Oh yeah, I run racing karts. Being new posting around these parts I really haven't done a very good job with the introduction. Both karts have slotted and drilled brake rotors - the shifter is Brembo brakes.

I appreciate all you gents taking the time to share your expertise and experience.

SAW

Uncle's toy (Milwaukee Bullet) with cousin driving: (I assisted with initial outrigger design)

Milwaukee%20Bullet.JPG


My toys:

Karts%20Rear%20View%20II%20%28Medium%29%20%282%29.jpg


Me in the Rotax at the track:

Rotax.jpg


And hey, with high performance toys, I recommend high performance securith to guard them:

Beau1%20%28Small%29.jpg
 
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Drilled and sloted rotors are designed to scrub the pad material down, thus keeping the pads from glazing which is only needed under racing conditions, thus wearing pads out faster.


slots are for shaving the surface to prevent glazing (not needed with good modern pads)
cross drilling is strictly for weight reduction (and looks)

both reduce friction surface... less friction surface, less braking force

cross drilled rotors are also more likely to crack under racing stresses
hell most cross drilled rotors say right on them that they are not for track use
 
Here's a picture of one of the rotors :

PICT2156%20%28Large%29.JPG


Based upon what I've heard thus far and a little common sense, it looks like they will accomplish exactly what I'm looking for. i.e. reduction of stopping force on the front. Hopefully, they won't warp as easily as the stock ones.
 
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they look like either EBCs or EBC clones
the slots shave the pad surface
the "dimples" give the cool look of cross drilled rotors

will they stop the car? :yes:
would you have been better off with brembo blanks and some good pads? :yes:
 
brembo blanks and HPS pads all the way around in my setup :)

then again, i have massive two-piston fronts and massive rears... from AWD cars.
 
I have Brembo's front and rear on the shifter kart. Don't really need that extreme on the daily driver.

* Final post on this one for anyone interested.

Slotted and drilled rotors not being suitable for racing applications. Yes, there are cheap knock off garbage parts out there made from inferior materials and dressed up to "Look" like high performance/racing parts i.e.slotted and/or drilled. These are junk rotors that are drilled, slotted, whatever for cosmetic reasons that are probably not suited for ANY installation, let alone racing. Many a racing brake rotor is slotted and drilled - it's a fact. Rotors on my racing karts and any racing kart I have ever seen are slotted and drilled. NASCAR, etc.

Brembo - Brake systems

The premise of this thread - to BALANCE an UNBALANCED braking system. Balancing an unbalanced (front to rear) braking system will ALWAYS result in a shorter stopping distance all things equal. i.e. fade, heat performance, etc. Changing from organic, to metallic, to ceramic front pads has proportionally changed the pedal pressure required to stop the car. It has also changed the problem of premature front wheel lock up during hard breaking or breaking on wet pavement.

I picked up a set of ceramic front pads ~6 months ago and finally got around to installing them. After a month of driving and having them now seated in,l I can say they work well.

The brakes are now the best they have ever been, especially on wet streets.

Short of adjustable proportioning and changing to rear discs, I think it's about as good as it's going to get. Plenty fine for a dd application.

And yes, the stopping distance is improved - shorter. It still has plenty of system pressure to lock up both Nitto's up front on dry pavement. And now the rears lock up and skid too.

Oh and the front rotors on it don't warp any more - yahoo!!!! They came from: http://brakeperformance.com

Thanks guys!!!
 
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Brakes are only drilled where weight reduction is needed and slight decrease in brake performance is not an issue(ie a very light vehicle or races where brakes aren't used very often). You're not going to find much drilled rotors in many high performance road-course vehicles(GT, F1, MotoGP, etc.)

Stock, many cars are front-biased just because it's safer. Instead of decreasing front braking force, just increase rear.
 
Increase the rear? How? Why put a complex/expensive solution on a simple problem?

Front biased safer? Most have anti-locks these days don't they?

I'm not running drilled rotors - they are grooved and dimpled. At this point they are performing better than the OEM's did.

Thanks for the help.
 
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These days, yes, but not yesterday's cars(ie: the 88-91 Civics). Even then, ABS just helps prevent the wheels from locking up; they don't necessarily help with overall brake performance(on brake tests, ABS is usually disabled...they're mainly designed for wet driving, etc. You can't really use them as a band-aid so to say).
 
True enough. So, how to increase rear? Nice motor pic you have there BTW.

So you are suggesting they purposely designed the Civic's (and other cars) to be front biased on the brakes? Wow! I had no idea. I'm probably a little more picky than the average driver on brakes since I have the karts.

Well, they are pretty good now - much better than when I started this thread. There is a hill with a stoplight and cross street at the bottom I used to go sliding down in the morning's on the way to work when it rained. Dangerous. Situation is way better now.
 
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More aggressive rear shoes like Porterfields R-4/R-4S(R-4 are race pads btw). There's not much shoes to pick from, but there's a lot of front pads; so just find a slightly less aggressive front pad in comparison to what's used in the rear.

Thanks; that's actually an old picture and it'll look different hopefully by the end of this year(it'll definitely output more power though ;) ).
 
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