BrakeExpert's Brake Chart Thread - Civic Brake Upgrades for EF, EG, EK and Integras

[Tylermiller888]

You said 96-00 Brake Booster's are all the same, but do you know if they or an EG's brake booster will fit an Integra with ABS? I need a brake booster bad, and don't have much money, because someone droppped a truck on my foot and I can't work, so I'm being forced to buy a used one, and I need to know if there are any other options other than Integras.

[HickamHatch]

Originally Posted by BrakeExpert

to >11.1CL
Go here for details: http://www.honda-tech.com/zerothread?id=2211498 This requires a good bit of machine work. Get the caliper mounting bracket, grinded 4.7mm off of the surface where it mounts to the knuckle. Grind the middle of the edges of the throat of the caliper body about 1mm in and 40mm wide. Grind the bracket at the point where it contacts the hub area of the knuckle. Grind the hangar on the underside roughly 2mm to prevent contact with the rotor's hat. Get 1996 Prelude VTEC rotors re-drilled to fit the 4x100 hub. Get 1996 Prelude VTEC rotors re-drilled to fit the 4x100 hub. Get a plastic hammer and carefully bend the dust shield back so that the rotor's back surface does not touch. Get the caliper mounting bracket grinded 3.7 mm off of the surface where it mounts to the knuckle. Get a set of custom made hub centering rings for the rotor. Take the 99-00 RL calipers, pads, modified brackets, Prelude VTEC rotors and custom aluminum centering hub rings and swap them onto the Civic DX.

which measurement is the correct one?

[BrakeExpert]

My bad. I haven't modified that in a while since I discontinued it. Neither are correct, I'll remove it from the chart.

[HickamHatch]

So will it just bolt on?

Besides modifying for it to clear.

By bolt on, I mean you dont have to machine the bracket down for it to have the correct offset

[BrakeExpert]

No it doesnt bolt on.

[JDogg]

Where can I get some hub-centric rings made up. I have a plan for a cheap s2000 brake upgrade, I'll know for sure what size rings later this week with any luck.

[94eg!]

Originally Posted by BrakeExpert

Brake Bias - Proportioning Valve


Swapping to a 96-99 CX or 99-00 Si prop. valve when installing rear discs.
The 99-00 Civic Si comes with the same shaped proportioning valve as any 96-00 Civic, so swapping the proportioning valve is a bolt on job, which can be done with a few offset brake line wrenches. The stock drum proportioning valve, when the brake pedal is applied, sends fluid to the rear drums only. This is because the drum shoes are a few millimeters from the drum, so the fluid initially moves the pads to touch the drum, whereas with a pad and rotor, the pad is so close that it brushes along the rotor while driving. After the shoe touches the drum, the proportioning valve sends fluid to the front calipers as well, and then acts as a hub for the fluid. So a rear drum intended prop. valve in a car with four wheel discs is not the end of the world.
The 99-00 SI proportioning valve acts as a hub more of the time, since the back brakes are calipers, there is no need to send so much fluid initially to the back brakes because they are calipers, and use pads that also brush against the rotor constantly. Therefore, a rear disc intended prop. valve in a car with front discs and rear drums would be very bad.
When you swap from drum to disc rear brakes, obviously its best that you use a prop. valve that was meant for it. Though I recommend that you install the 99-00 Si prop valve on your 96-00 Civic when you put rear discs on it, because of how it works, I do not have it on my rear disc equipped 1996 Civic. I do not track race, and have good tires, and on the streets, have not locked up the rear tires before the fronts because I can brake very hard and not lockup the tires. I do not have ABS.

Are you aware that the 99-00 Si has the same prop valve as the 96-00 Hatchbacks and HX trims (all rear drum)?

And your TL/Brembo calipers info should be as follows: TL 04-06 6MT and 07-08 Type-S.

And here is some more useful info from the Centric/Stoptech database:

Chassis, F Piston, R Piston, Master, F Rotor, R Rotor
- EF – HF, 50.8mm, drums, 13/16th, 31/17mm
- EF - DX, Std, LX, Fwd Wgn, 50.8mm, drums, 13/16th, 240/21mm
- EF - 88-89 Si, 50.8mm, drums, 13/16th, 240/21mm
- EG - DX, LX CX, VX, 50.8mm, drums, 13/16th, 240/21mm
- EG - Si, 50.8mm, 30mm, 13/16th, 240/21mm, 239/10mm
- EK - DX, LX, CX, HX, GX, 50.8mm, drums, 13/16th, 240/21mm
- EK - GX ABS, 50.8mm, drums, 7/8th, 240/21mm
- Del Sol - S, 50.8mm, drums, 13/16th, 240/21mm
- Del Sol - Si, 50.8mm, 30mm, 13/16th, 240/21mm, 239/10mm
- EF - 4WD Wagon & 90-91 Si, 54mm, 30mm, 7/8th, 242/19mm, 239/10mm
- EG - JDM EG6 SiR 2, 54mm, 30mm, 7/8th, 262/21mm, 239/10mm
- EG - EX Coupe Non-ABS, 54mm, drums, 7/8th, 262/21mm
- EK - EX Non-ABS, 54mm, drums, 7/8th, 262/21mm
- EK - EX ABS, 54mm, drums, 15/16th, 262/21mm
- EK - Si, 54mm, 30mm, 7/8th, 262/21mm, 239/10mm
- Del Sol - VTEC Non ABS, 54mm, 30mm, 7/8th, 262/21mm, 239/10mm
- Del Sol - VTEC ABS, 54mm, 30mm, 15/16th, 262/21mm, 239/10mm
- EF - EX, 57mm, 30mm, 15/16th, 262/21mm, 239/10mm
- EG - Si ABS, EX ABS, 57mm, 30mm, 15/16th, 262/21mm, 239/10mm
- DA - Non ABS, 57mm, 30mm, 15/16th, 262/21mm, 239/10mm
- DA - ABS, 57mm, 30mm, 1”, 262/21mm, 239/10mm
- DC - RS Non ABS, 57mm, 30mm, 15/16th , 262/21mm, 239/10mm
- DC - GS, LS, GSR ABS, 57mm, 30mm, 1”, 262/21mm, 239/10mm
- DC - TYPE R ABS, 57mm, 34mm, 1”, 281.6/23mm, 59.7/9mm

- EP - Si ABS, 54mm, 34mm, 7/8”, 262/21mm, 259.9/10mm
- S2000 - ABS, 54mm , 40mm, 1”, 299.6/25mm, 281.6/11.9mm
- NSX - NA1 ABS, 36/40, 43mm, 1”, 282/28mm, 282/21mm
- NSX - NA2 ABS, 34/40, 1”, 297/28mm, 302/22.9mm
- TL 2004-2008 (Brembo) , 38/42mm, 38mm, 13/16”, 310/24.9mm, 282/9mm
- LEGEND - 93+ 2dr, GS ABS, 38/43mm, 38mm, 1”, 282/28mm, 282/9mm

Piston Area
50.8mm = 2026.8mm/sq
NA2 = 2196.2mm/sq
54mm = 2290.2mm/sq
NA1 = 2306.1mm/sq
TL = 2519.6mm/sq
57mm = 2551.8mm/sq
Legend = 2586.3mm/sq

If you look closely, you will find some interesting facts...
- Rear discs don't effect master cylinder size
- ABS does effect master cylinder size (bumps it up 1 notch)
- EP3 has Type-R sized 4x100 rear brakes

[BrakeExpert]

Yeah I'm aware. Maybe I should update this. After years of driving my EK and many many brake combinations, I got a new rule of thumb: Don't change your prop valve.

[HickamHatch]

I have a 95 CX civic. Want to use the CL front brakes with 92-95 si rear brakes. What do you recommend for the prop valve?

[Kozy.]

Originally Posted by BrakeExpert

Yeah I'm aware. Maybe I should update this. After years of driving my EK and many many brake combinations, I got a new rule of thumb: Don't change your prop valve.

Even despite the fact that drums take way less pressure to generate a set amount of torque than discs do?

[94eg!]

I would agree that a new prop valve is a good idea. The problem is which one do you really pick. Just one from a rear disc setup, or one from a similar chassis. Which is more important. Even Honda uses the same prop valve for Disc & Drum setups on the EK. This is why it becomes so confusing. It would awesome if we could get a collection of prop valves and test them for comparison.

[Kozy.]

A prop valve test would solve all. Interesting to note that only US model Hondas appear to use the same prop valve part number between drum and discs, JDM models have different props even between different disc models which makes sense.

Laziness/sloppy engineering/typo by Honda America perhaps?

[BrakeExpert]

Lemme clarify:

I've run 44 different brake combinations, from stock, to NSX Type-R brakes on all 4 wheels, to NSX rear discs and Ferrari F430 fronts. ALL of these setups had my stock drum prop valve. So a message to other EK owners. You do NOT need to change the prop valve. if you want to talk theory, I'll make a new page.

[Kozy.]

Lets talk theory. As I've said elsewhere on these pages, the fact that you can run NSX rear brakes on a Civic is evidence that the drum prop is seriously underworking any disc setup. If you try running those brakes with a correctly proportioned disc brake prop valve, (assuming a 10% total front bias) you'd be locking the rear wheels under anything more than a moderately enthusiastic stop.

You don't need to swap the prop when doing a disc conversion, sure, but if you actually want them to work as well as looking nice then it's probably advisable.

[94eg!]

Originally Posted by BrakeExpert

Lemme clarify:

I've run 44 different brake combinations, from stock, to NSX Type-R brakes on all 4 wheels, to NSX rear discs and Ferrari F430 fronts. ALL of these setups had my stock drum prop valve. So a message to other EK owners. You do NOT need to change the prop valve. if you want to talk theory, I'll make a new page.

Yeah, but did you ever do any stopping distance tests with all those setups? This is the true measure of brake bias performance. Without direct comparisons like that, you have no idea if your brakes are REALLY any better or any worse. Sure you will be able to lock up some wheels with any setup, but butt dynos aren't worth much.

[Libertariat]

The real problem is figuring out what the hell prop valve to use on a 6th gen civic:

46210-S04-902 VALVE ASSY., PROPORTIONING 2000 CIVIC CX Hatch
46210-S04-902 VALVE ASSY., PROPORTIONING 2000 CIVIC DX Hatch <- what I drive
46210-S04-902 VALVE ASSY., PROPORTIONING 2000 CIVIC DX Coupe
46210-S04-902 VALVE ASSY., PROPORTIONING 2000 CIVIC HX Coupe
46210-S04-902 VALVE ASSY., PROPORTIONING 2000 CIVIC SI Coupe <- what I theoretically need, since it has rear disks

46210-S04-912 VALVE ASSY., PROPORTIONING 2000 CIVIC DX Sedan
46210-S04-912 VALVE ASSY., PROPORTIONING 2000 CIVIC DX-V Sedan
46210-S04-912 VALVE ASSY., PROPORTIONING 2000 CIVIC LX Sedan
46210-S04-922 VALVE ASSY., PROPORTIONING 2000 CIVIC GX Sedan
46210-S04-962 VALVE ASSY., PROPORTIONING 2000 CIVIC EX Coupe

[Kozy.]

This is certainly a point of confusion, the requirements of disks and drums are completely different with discs requiring a lot more pressure.

As I mentioned, this seems to be a peculiarity with US models only, UK and JDM models do have different valves.

[BrakeExpert]

Lets go start a new prop valve debate thread.

[Kozy.]

Prop valve / general brake theory. I like the sound of that.

There is more to brakes than just what bolts up.

[BrakeExpert]

Yes but theres not a lot to change. Trust me, I've been doing brakes on Civics for YEARS. I've done all the research, taken the guess work out for ya. Follow the guidlines and you don't have to think. I can go on and on, but if ya go by that chart, your bias will be fine.

[Kozy.]

I'm not one to take what anyone says as gospel, I prefer to figure it all out for myself, and my research says NSX brake are dangerously rear biased if you use the same proportioning that would give a stock Type R a 10% front bias.

Here's some numbers for you.

10.2" DC2R rear brakes generate .214lbft/psi
10.2" NSX rear brakes generate .363lbft/psi

That's an increase of nearly 70%. If we assume that the stock Type R holds the rear tyres pretty close to their saturation limit at the design threshold limit, that 10% say, then how are they going to handle 70% more brake torque?

One might suggest that they could handle that with a 70% reduction in pressure, perhaps in the shape of a drum prop valve?

[94eg!]

Komodo, How do you calculate the torque/psi. I was doing some simple comparison calcs (piston area x 2 x rotor diameter), but I'm not sure that's the right way to do it. Same comparison with my crappy math got me NSX brakes being 73% stronger than ITR. That is assuming my following piston / rotors are correct.

ITR rears 34mm / 259.7mm
NA1 rears 43mm / 282mm

[Kozy.]

You're correct, my model incorporates the pad radial height (effective radius instead of rotor OD) and an allowance for compliance which is why the figures are slightly different.

[94eg!]

Good to know. Thanks. So my simple math is a good way of comparing front to rear and before and after changes on the same chassis (given the same pad compound)? If so then that's good. It makes it really easy to choose the correct size rotor for a given caliper, or vice verse when doing hybrid brakes. Here are some recent static front to rear bias numbers I cranked out for comparison on stock setups (all US spec chassis). None of this takes into account prop valves. But according to the OEM service manuals, the bias valve doesn't begin it's rear line reduction effect until about the the 50% foot pressure range...

Chassis: Front Bias/Rear Bias
92-95 Si: 74.2%/25.8%
Del Sol VTEC (same as EG6 SiR): 78%/22%
^Above + EP3 Rear Rotors: 76.6%/23.4%
^Above + ITR Rear calipers: 71.8%/28.2%
94-01 Integra: 79.8%/20.2%
97+ ITR:75.3%/24.7%

Now I've personally run the 92-95 Si brake setup on my CX, and I can say for sure it was VERY aggressive in the bias department. That setup stock is very close to being unstable with a 4040 prop valve. I had higher friction Axxis pads in the rear and I had no trouble locking up 1 rear tire with a lot of foot pressure. I've since gone the Del Sol VTEC route, and plan on adding EP3 rear rotors in the future. This should get me close to the ITR bias without breaking the bank on my 100% street car. I definitely don't want to go more rear bias than an ITR since my CX has a shorter wheel base (adds rear bias). But my car is also lowered, which also brings back some front bias too. lol

[Kozy.]

Whilst a simple pressure/torque calculation is good for comparing different setups on a given axle, the static bias won't give you the full picture. Dynamic bias (the 10% I mentioned above) is a lot more tricky to determine unfortunately.

One thing that you hve to account for is that with a bigger front setup, system pressure will be lower, which means rear force will be lower and the bias goes even more forwards than the static figures would suggest.